Psychological Science: The Science of Behavior, Thought, and Experience, Exams of Psychology

Download Psychological Science: The Science of Behavior, Thought, and Experience and more Exams Psychology in PDF only on Docsity! 1 Psychological Science Final Exam Review Guide 1.1 The Science of Psychology  Psychology is the scientific study of behavior, thought, and experience. o Psychology is a vast discipline. Better yet, a collection of disciplines composed of many overlapping fields of study. o Two unifying qualities allow us to group all these fields into the category of psychological science. ▪ First, psychology involves the study of behavior. This can include perceptions, thoughts, and emotions. ▪ Second, psychologists employ the scientific method in their work.  The scientific method is a way of learning about the world through collecting observations, proposing explanations for the observations, developing theories to explain them, and using the theories to make predictions. o Whether a field of study is a science, or a specific type of research is scientific, is based not on the subject but on the use of the scientific method. o It involves a dynamic interaction between hypothesis testing and the construction of theories. o Theory > Hypothesis > Test hypothesis > Confirm or reject hypothesis  A hypothesis (plural: hypotheses) is a testable prediction about processes that can be observed and measured. o A testable hypothesis is one that can be confirmed or rejected (you do not prove a hypothesis), and a scientific hypothesis must be testable.  Pseudoscience refers to ideas that are present as science but do not actually utilize basic principles of scientific thinking or procedure. o Astrology is a pseudoscience because unlike science, there is no scientific basis around it. Scientists are eager to test hypotheses whereas astrologists would rather you just take their word for it.  A theory is an explanation for a broad range of observations that also generates new hypotheses and integrates numerous findings into a coherent whole. o Hypotheses are a major component of scientific theories. o Theories are built from hypotheses that are repeatedly tested and confirmed; in turn, good theories eventually become accepted explanations of behavior or other natural phenomena. o Similar to hypotheses, an essential quality of scientific theories is that they can be proved false with new evidence. In fact, any scientific theory must be falsifiable. The process helps to ensure that science is self-correcting – bad ideas typically do not last long in the sciences. o Theories are not the same thing as opinions or beliefs. o All theories are not equally plausible. There are good theories, and there are not-so-good theories. o A measure of a good theory is not the number of people who believe it to be true. For example, 39% of Americans believe in the theory of evolution by natural selection, despite the fact that it is the most plausible, rigorously tested theory of biological change and diversity.  The biopsychosocial model is a means of explaining behavior as a product of biological, psychological, and sociocultural factors. o Biological influences on our behavior involve brain structures, chemicals, hormones, and drug effects. Your family, peers, and immediate social situation also determine how you think, feel, and behave. Culture and gender can also influence human behavior. o Behavior can be fully explained only if multiple perspectives are incorporated.  Scientific literacy is the ability to understand, analyze, and apply scientific information. o Scientific literacy has several key components, starting with the ability to learn new information. o Being scientifically literate is to be able to read and interpret new terminology, or know where to go to find out more. Individuals should also be able to use their thinking skills to evaluate information and claims.  Critical thinking involves exercising curiosity and skepticism when evaluating the claims of others, and with our own assumptions and beliefs. o For psychologists, critical thinking means that we apply scientific methods carefully, examine our assumptions and biases, and tolerate ambiguity when the evidence is inconclusive. o Curiosity is essential to psychology because many of us think about the causes of behavior only when it affects us negatively or when it strikes us as unusual. As psychologists, we are always curious and ask questions about all kinds of behaviors – not just the unusual or problematic. Because we are curious, psychological theories should provide meaningful explanations for all behaviors. o Skepticism and curiosity is viewed as a means of raising important questions; both lead us to search 2 for and evaluate new evidence. 5 aggressive impulses. He believed that when a person is hypnotized, the psychoanalyst could have more direct access into the individual’s unconscious mind. o The medical model is an approach involving the use of medical ideas to treat disorders of emotions, thought, and behavior.  Sir Francis Galton believed that heredity (genetics) explained psychological differences among people. It fit his beliefs about social class. For example, he noticed that great achievement tended to run in families. o To support his beliefs, Galton developed ways of measuring what he called eminence, a combination of ability, morality, and achievement. o He took on the question of nature and nurture relationships, the inquiry into how heredity (nature) and environment (nurture) influence behavior and mental processes. o Galton pursued scientific justification for eugenics, which literally means “good genes,” and promoted the belief that only intelligent, talented individuals should have children. o Biological psychology seeks to explain the underlying genetic, physiological, and brain basis for behavior.  The Beginnings of Contemporary Psychology o Wilhelm Wundt’s primary research method was introspection, meaning, “to look within.” It required a trained volunteer to experience a stimulus and then report each individual sensation he or she could identify through introspection. He developed reaction time methods as a way of measuring mental effort. Wundt found that mental activity is not instantaneous and requires a small amount of effort measured by the amount of time it takes to react.  Structuralism was an attempt to analyze conscious experience by breaking it down into basic elements, and to understand how these elements work together. o Edward Titchener believed that mental experiences were made up of a limited number of sensations, which were analogous to elements in physics and chemistry. According to Titchener, different sensations can form and create complex compounds, just like hydrogen and water can combine to form water – H2O.  Functionalism is the study of the purpose and function of behavior and conscious experience. o The incorporation of Darwin’s ideas can be found today in the modern field of evolutionary psychology, an approach that interprets and explains human behavior in terms of forces acting upon our distant ancestors. According to this approach, the physical and social environment that our ancestors encountered has shaped our brains and behaviors.  Behaviorism is an approach that dominated the first half of the 20 th century of American psychology and had a singular focus on studying only observable behavior, with little to no reference to mental events or instincts as possible influences on behavior. o The credit for discovering classical conditioning went to Ivan Pavlov who showed dogs could learn to salivate to a tone if the tone has a history of sounding just prior to the delivery of food. o Credit for the rise of behaviorism in the United States went to John B. Watson. o B.F. Skinner was a behaviorist who had considerable influence over American psychology for several decades, and believed that psychology was the study of behavior and not of the unobservable mind.  Humanistic psychology focuses on the unique aspects of each individual human, each person’s freedom to act, his or her rational thought, and the belief that humans are fundamentally different from other animals. o Psychologists Carl Rogers and Abraham Maslow believed that humans strive to develop a sense of self and are motivated to personally grow and fulfill their potential.  The Cognitive Revolution o Hermann Ebbinghaus studied data on remembering and forgetting. The results of his studies produced “forgetting curves,” which showed that most of what a person learns will be forgotten rapidly, but then forgetting slows to a crawl. The forgetting curve is now a staple of modern psychology. o Frederick Bartlett illustrated that memory is an interpretive process that involves cultural knowledge. He demonstrated that, in a movie for example, we are more likely to remember the general storyline than details such as exact words in the script or what the characters were wearing. Our cultural knowledge shapes what we find important enough to remember. o Gestalt psychology is an approach emphasizing that psychologists need to focus on the whole of perception and experience, rather than its parts. “The whole is greater than the sum of its parts.” o Cognitive psychology is a modern psychological perspective that focuses on processes such as memory, thinking, and language. o Norman Triplett investigated how other people influence individual behavior and observed that cyclists ride faster in the presence of other people than when riding alone. o The field of social and personality psychology is the study of the influence of other people on our behavior along with what makes each individual unique. 6 o Kurt Lewin observed that behavior is a function of the individual and the environment, or B = f{I,E}. He meant that all behaviors could be predicted and explained through understanding how an individual with a specific set of traits would respond in a context that involved a specific set of conditions. o Cross-cultural psychology is the field that draws comparisons about individual and group behavior among cultures; it helps us understand the role of society in shaping behavior, beliefs, and values. 1.3 Putting Psychology to Work: Careers in Psychology and Related Fields Employment in Psychology (Table 1.3) Job Title Role Clinical psychologist Diagnosis and treatment of psychological disorders Counseling psychologist Treatment of psychological disorders and less severe psychological difficulties Neuropsychologist Diagnosis and evaluation of individuals with neurological damage School psychologist Diagnosing behavioral problems and learning disabilities; working in schools to develop personalized programs to help students Community psychologist Providing basic mental health services to the community with a focus on education and prevention Licensed clinical social worker; independent social worker Counseling individuals and families experiencing mental health and social problems; engaging in community organizations and providing social services Forensic psychologist Psychology related to judiciary or criminal issues, such as evaluating an individual’s competency to stand trial Psychiatrist Diagnosis and treatment of psychological disorders Psychiatric nurse Working as part of a comprehensive treatment team to manage medical and behavioral treatments on a regular basis Behavioral health technician; case manager Overseeing treatment on either an inpatient or outpatient basis, respectively  Research and Teaching o Applied psychology uses psychological knowledge to address problems and issues across various settings and professions, including law, education, clinical psychology, and business organization and management. o Your psychology instructor is employed (at least part of the time) in academic psychology. Such psychologists work at colleges and universities, and most combine teaching with conducting research.  Psychological Health and Well-Being o Psychiatry is a branch of medicine concerned with the treatment of mental and behavioral disorders. ▪ As physicians, psychiatrists are likely to prescribe drugs such as antidepressants. o Clinical and counseling psychologists are more likely to emphasize psychological approaches to treat 7 mental health concerns and disorders. Social workers are likely to emphasize the social context of the individuals in treatment, such as the family’s dynamics, socioeconomic status, and community. 10 o A single-blind study is one where the participants do not know the true purpose of the study, or else do not know which type of treatment they are receiving (for example, a placebo or a drug). o A double-blind study is one in which neither the participant nor the experimenter knows the exact treatment for any individual.  Sharing the Results o Peer review is a process in which papers submitted for publication in scholarly journals are read and critiqued by experts in the specific field of study. o Replication is the process of repeating a study and finding a similar outcome each time.  Anecdotal evidence is an individual’s story or testimony about an observation or event that is used to make a claim as evidence.  Appeal to authority is the belief in an “expert’s” claim even when no supporting data or scientific evidence is present.  Appeal to common sense is a claim that appears to be sound, but lacks supporting scientific evidence. 2.2 Scientific Research Designs  Descriptive research is not an attempt to explain a subject; instead, it is an opportunity to present observations about the characteristics of the subject.  A case study is an in-depth report about the details of a specific case. o These are particularly useful in describing symptoms of psychological disorders and detailed descriptions about specific successes or failures in treatment.  Naturalistic observation is when psychologists unobtrusively observe and record behavior as it occurs in the subject’s natural environment.  Surveys and Questionnaires o Surveys and self-reports are methods that include face-to-face interviews, phone surveys, paper-and- pencil tests, and web-based questionnaires, and they measure attitudes, opinions, beliefs, and abilities. o Despite the range in topics and techniques, their common element is that the individuals speak for themselves. o Surveys and questionnaires are still a method of observation, but the observations are provided by the people who are being studied rather than the psychologist.  Correlational research involves measuring the degree of association between two or more variables. o For example, consider the questions: “What are the high school graduation rates in each county of your state?” or “What are the typical family incomes in each county of your state?” o Correlations take a direction. They may be positive (both variables occur together) or negative (the more of one variable, the less of the other). o Correlations have a magnitude or strength. This magnitude is described in terms of a mathematical measure called the correlation coefficient, ranging from -1.0 to +1.0. The closer it is to the absolute value of 1.0, the stronger the relationship. A zero-correlation is when there is no association between the variables. o The correlation coefficient is a measure of association only – it is not a measure of causality. That is, correlation does not equal causation. In many cases, a correlation gives the impression that one variable causes the other, but that relationship cannot be determined from correlational research. ▪ For example, good humor is associated with good health, but that does not mean good health is responsible for the good health. ▪ The third variable problem refers to the possibility that a third unmeasured variable is actually responsible for a well-established correlation between two variables.  Experimental Research o The Experimental Method ▪ Random assignment is a technique for dividing samples into two or more groups. ▪ Confounding variables are variables outside of the researcher’s control that might affect the results. ▪ The dependent variable is the observation or measurement that is recorded during the experiment and subsequently compared across all groups. ▪ The independent variable is the variable that the experimenter manipulates to distinguish between the two groups. ▪ The experimental group is the group in the experiment that is exposed to the independent variable. ▪ The control group is the group that does not receive the treatment and, therefore, serves as a comparison. 11 o Quasi-experimental research is a research technique in which two or more groups that are compared are selected based on predetermined characteristics, rather than random assignment. 12 2.3 Ethics in Psychological Research  Promoting the Welfare of Research Participants o The institutional review board (IRB) is a committee of researchers and officials at an institution charged with the protection of human research participants. o The IRB is intended to protect individuals in two main ways: ▪ The committee weighs potential risks to the volunteers against the possible benefits of the research. ▪ It requires that volunteers agree to participate in the research.  Weighing the Risks and Benefits of Research o Physical risks are rare in psychological research. More common are measures that involve possible cognitive and emotional stress, for example: ▪ Mortality salience. In this situation participants are made more aware of death. ▪ Writing about upsetting or traumatic experiences. People are asked to write about negative experiences in great detail, sometimes repeatedly.  Obtaining Informed Consent o Researchers must ensure that human volunteers truly are volunteers. o Informed consent is the concept in which a potential volunteer must be informed (know the purpose, tasks, and risks involved in the study) and give consent (agree to participate based on the information provided) without pressure. ▪ Volunteers should be told, at minimum, the topic of the study, the nature of any stimuli to which they will be exposed, the nature of any tasks, the approximate duration of the study, any potential physical, psychological, or social risks involved, and the steps that the researchers have taken to minimize those risks. o Deception is misleading or only partially informing participants of the true topic or hypothesis under investigation. o Debriefing is when researchers explain the true nature of the study, and especially the nature of and reason for the deception. o The elements in determining whether full consent is given are: ▪ Freedom to choose. Individuals should not be at risk of anything if they choose not to participate. ▪ Equal opportunities. Volunteers should have choices. ▪ The right to withdraw. Volunteers should have the right to withdraw from the study, at any time, without penalty. ▪ The right to withhold responses. Volunteers responding to surveys or interviews should not have to answer any question that they feel uncomfortable answering.  The Right to Anonymity and Confidentiality o Anonymity means that the data collected during a research study cannot be connected to individual participants. o Confidentiality includes at least two parts. First, researchers cannot share specific data or observations that can be connected with an individual. Second, all records must be kept secure so that identities cannot be revealed unintentionally.  Ethical Collection, Storage, and Reporting of Data o Reported data should be kept for a reasonable amount of time – generally, 3 to 5 years – in case other researchers may request access to the data to reinterpret it, or perhaps examine the data before attempting to replicate the findings. o Some researchers experience great external pressure to obtain certain results, but scientists must be honest with their data. o Scientific misconduct arises when individuals fabricate or manipulate their data to fit their desired results. 15 3.2 How the Nervous System Works: Cells and Neurotransmitters  Neural Communication o Neurons are one of the major types of cells found in the nervous system, which are responsible for sending and receiving messages throughout the body. o The cell body (also known as the soma) is the part of a neuron that contains the nucleus that houses the cell’s genetic material. o Dendrites are small branches radiating from the cell body that receive messages from other cells and transmit the message toward the cell body. o The axon is the structure that transports information from the neuron to neighboring neurons in the form of the electrochemical reactions. At the end of the axon are axon terminals. ▪ Located within the axon terminals are chemicals called neurotransmitters, the chemicals that function as messengers allowing neurons to communicate with each other. ▪ Neurotransmitters are released across synapses, the microscopically small spaces that separate individual nerve cells. o Not all neurons are the same – they differ in form and function. o Sensory neurons fetch information from the bodily senses and bring it towards the brain. o Motor neurons carry messages away from the brain and spinal cord and toward muscles in order to control their flexion and extension.  Glial cells o Myelin is a fatty sheath that insulates axons from one another, resulting in increased speed and efficiency of neural communication. o Myelin is made from a highly abundant type of cell called glia (Greek for “glue”). o Glial cells are specialized cells of the nervous system that are involved in mounting immune responses in the brain, removing wastes, and synchronizing activity of the billions of neurons that constitute the nervous system.  The Neuron’s Electrical System: Resting and Action Potentials o The inner and outer environments of a neuron differ in their concentrations of charged atoms called ions. In other words, the neuron is polarized. o Resting potential refers to a neuron’s relatively stable state during which the cell is not transmitting messages. ▪ At resting potential, the outside of the neuron has a relatively high concentration of positively charged ions while the interior has fewer positively charged ions as well as relatively high concentrations of negatively charged ions. ▪ The difference in charge between the inside and outside of the cell leaves the inside of the axon with a negative charge of approximately -70 millivolts (mV). ▪ When stimulated the neuron springs into action, a process referred to as neural firing. o Action potential is a wave of electrical activity that originates at the base of the axon and rapidly travels down its length. ▪ Neurons have specific thresholds that must be reached before it will fire. When the threshold is reached, the neuron then initiates an action potential. o When the action potential reaches the axon terminals at the end of the cell, neurotransmitters are released into the synaptic cleft. o The synaptic cleft is the minute space between the terminal button and the dendrite, and bind to receptors on the dendrites of neighboring neurons. o The action potential is followed be a refractory period, a brief period in which a neuron cannot fire. o When stimulated, a given neuron always fires at the same intensity and speed. This activity adheres to the all-or- none principle. o The all-or-none principle is that individual nerve cells fire at the same strength every time an action potential occurs. ▪ Neurons do not “sort of” fire, or “over-fire” – they just fire. ▪ The strength of a sensation is determined by the rate at which nerve cells fire as well as by the number of nerve cells that are stimulated. A stimulus is experienced intensely because a greater number of cells are stimulated, and the firing of each cell occurs repeatedly.  The Chemical Messengers: Neurotransmitters and Hormones o When neurotransmitters are released at the axon terminal, they cross the synapse and fit in a particular receptor of the dendrite like a key in a lock. If the neurotransmitter binds to the receptor, it will trigger one of two types of reaction 16 in the receiving neuron: The effect can be either excitatory, increasing action potentials, or it may be inhibitory, decreasing action potentials. o Neurotransmitter molecules that have bound to postsynaptic receptors are released back into the synaptic cleft where they may be broken down by enzymes. Others might go through reuptake. o Reuptake is a process whereby neurotransmitter molecules that have been released into the synapse are reabsorbed into the axon terminals of the presynaptic neuron. ▪ Reuptake serves as a sort of natural recycling system for neurotransmitters as is also a process that is modified by many commonly used drugs. For example, selective serotonin reuptake inhibitors (SSRIs) inhibit reuptake of the neurotransmitter serotonin, eventually increasing the amount of serotonin available at the synapse.  Types of Neurotransmitters o Monoamines are one class of neurotransmitter. They are known to influence mood, and the major antidepressant drugs on the market influence their activity. o Dopamine is a monoamine neurotransmitter involved in such varied functions as mood, control of voluntary movement, and processing of rewarding experiences. o Serotonin is a monoamine involved in regulating mood, sleep and appetite. o Norepinephrine is a monoamine synthesized from dopamine molecules that is involved in regulating stress responses, including increasing arousal, attention, and heart rate. o Acetylcholine is one of the most widespread neurotransmitters within the body, found at the junctions between nerve cells and skeletal muscles; it is very important for voluntary movement. Major Neurotransmitters and Their Functions (Table 3.1) Neurotransmitter Some Major Functions Acetylcholine Movement, attention Dopamine Control of movement, reward-seeking behavior, cognition and attention Norepinephrine Memory, attention to new or important stimuli, regulation of sleep and mood Serotonin Regulation of sleep, appetite, mood Glutamate Excites nervous system, memory and autonomic nervous system reactions GABA (gamma-amino butyric acid) Inhibits brain activity, lowers arousal, anxiety, and excitation, facilitates sleep o GABA (gamma-amino butyric acid) is a primary inhibitory neurotransmitter of the nervous system, meaning that it prevents neurons from generating action potentials. o Glutamate is an excitatory neurotransmitter in the nervous system that is critical to the processes of learning and memory.  Drug Effects on Neurotransmission o Agonists are drugs that enhance or mimic the effects of a neurotransmitter’s action. o Antagonists inhibit neurotransmitter activity by blocking receptors or preventing synthesis of a neurotransmitter.  Hormones and the Endocrine System o Hormones are chemicals secreted by the glands of the endocrine system. ▪ With help from the nervous system, the endocrine system contributes to homeostasis – the balance of energy, metabolism, body temperature, and other basic functions that keeps the body working properly. o The hypothalamus is a brain structure that regulates basic biological needs and motivational systems. ▪ The hypothalamus stimulates the pituitary gland – the master gland of the endocrine system that produces hormones and sends commands about hormone production to the other glands of the endocrine system. o Adrenal glands are a pair of endocrine glands located adjacent to the kidneys that release stress hormones, such as cortisol and epinephrine. o Endorphin a hormone produced by the pituitary gland and the hypothalamus that functions to reduce pain and induce feelings of pleasure. ▪ Morphine – a drug derived from the poppy plant – binds to endorphin receptors. Morphine molecules fit into the same receptor sites as endorphins and, therefore, produce the same painkilling and euphoric effects. o Testosterone is a hormone that serves multiple functions, including driving physical and sexual development over the long term, and surging through sexual activity and in response to threats. 17 ▪ This hormone is often cited as an explanation for behavior. It is tempting to conclude that if a behavior has a biological explanation, then the behavior cannot change – and testosterone provides a great example. 20  The Midbrain: Sensation and Action o The midbrain resides just above the hindbrain and primarily functions as a relay station between sensory and motor areas. o A midbrain structure called the tectum coordinates the sensation of motion with actions. o The midbrain also includes neurons that contain very dense concentrations of dopamine receptors and activity. These neurons send messages to higher brain centers involved in the control of movement.  The Forebrain: Emotion, Memory, and Thought o The forebrain is the most visibly obvious region of the brain and consists of multiple interconnected structures that are critical to such complex processes as emotion, memory, thinking, and reasoning. o The basal ganglia are involved in facilitating planned movements, skill learning, and are also integrated with the brain’s reward system. ▪ People who are very practiced at a given motor skill (for example, playing an instrument or riding a bicycle) have actually modified their basal ganglia through practice to better coordinate engaging in the activity. ▪ Some parts of the basal ganglia are also involved in emotion, particularly experiences of pleasure and reward. o The limbic system is an integrated network involved in emotion and memory. ▪ The amygdala facilitates memory formation for emotional events, mediates fear responses, and appears to play a role in recognizing and interpreting emotional stimuli, including facial expressions. o The hippocampus (Greek for “seahorse” – something it physically resembles), is critical for learning and memory, particularly the formation of new memories. o The thalamus is involved in relaying sensory information to different regions of the brain.  The Cerebral Cortex o The cerebral cortex is the convoluted, wrinkled outer layer of the brain that is involved in multiple higher functions, such as thought, language, and personality. o This highly advanced, complex structure has increased dramatically in size as the primate brain has evolved. o The size of the brain is due to the size of the skull, constrained by the birth canal. Since the skull can only be so large, the brain has countered this constraint by forming a wrinkled surface – thereby increasing its surface area. More surface area means more neurons and, possibly, greater cognitive complexity. o Cerebrospinal fluid cushions the brain from impact against the skull. o Corpus callosum is a collection of neural fibers connecting the two hemispheres. o The cerebral hemispheres consist of four major areas, known as lobes: the frontal, parietal, occipital, and temporal lobes. o The frontal lobes are important in numerous higher cognitive functions, such as planning, regulating impulses and emotion, language production, and voluntary movement. ▪ The frontal lobes also allow you to deliberately guide and reflect on your own thought process. ▪ Toward the rear of the frontal lobes is a thick band of neurons that form the primary motor cortex, which is involved in the control of voluntary movement. o The parietal lobes are located behind the frontal lobes and are involved in our experiences of touch as well as bodily awareness. ▪ Adjacent to the primary motor cortex and at the front edge of the parietal lobe is the somatosensory cortex – a band of densely packed nerve cells that register touch sensations. o The occipital lobes are located at the rear of the brain, where visual information is processed. o The temporal lobes are located at the sides of the brain near the ears and are involved in hearing, language, and some higher-level aspects of vision such as object and face recognition. o Your own personal experiences play a role in how the architecture of your cerebral cortex develops. For example, experienced musicians develop a greater density of brain matter in the areas of the motor cortex of the frontal lobe as well as in the auditory cortex.  Left Brain, Right Brain: Hemispheric Specialization o The two sides of the cortex often perform very different functions, a phenomenon called hemispheric specialization. o Generally, the right hemisphere is specialized for cognitive tasks that involve visual and spatial skills, recognition of visual stimuli, and musical processing. In contrast, the left hemisphere is more specialized for language and math. o Creative artists and those who rely on intuition are often described as “right-brained,” whereas logical 21 and analytical types are supposedly “left-brained.” o In the mid-1800s, French surgeon Paul Broca identified an area on the left frontal lobe, called Broca’s area, which is responsible for complex grammar and speech production. Loss of speech is referred to as Broca’s aphasia. 22 o Another language region, Wernicke’s area, is located in the left temporal lobe, extending into the adjacent parietal lobe, and is involved in the comprehension of speech. Thus patients with Wernicke’s aphasia have difficulty with speech comprehension.  Electrophysiology o An electroencephalogram (EEG) measures patterns of brain activity with the use of multiple electrodes attached to the scalp. o The neural firing of the billions of cells in the brain can be detected, amplified, and depicted in an electroencephalogram. o An EEG can tell us a lot about general brain activity during sleep, wakefulness, and while patients or research participants are engaged in a particular cognitive activity. o A drawback is this technique does not allow researchers to probe directly inside the brain.  Brain Imaging o To obtain actual images of the brain, researchers turn to techniques such as positron emission tomography (PET) scans. ▪ A low level of radioactive glucose is injected into the blood and its movement to regions of the brain engaged in a particular task is measured. ▪ This technique allows researchers to monitor brain activity while a person performs a task such as reading or viewing emotionally charged stimuli. The greatest strength of PET scans is it can show the metabolic activity of the brain. A drawback is that PET scans take a long time to acquire – which is a problem when you want to see moment-by-moment activity of the brain. o Magnetic resonance imaging (MRI) is a technique that can be used to acquire highly detailed images of brain anatomy via exposure to a strong (and harmless) magnetic field. ▪ MRI allows us to observe brain activity through a technique called functional MRI (fMRI), where the difference between blood cells with an oxygen molecule attached versus those without is measured. ▪ fMRI provides a moment-by-moment picture of brain activity. o Magnetoencephalography (MEG) measures the tiny magnetic fields created by the electrical activity of nerve cells in the brain. ▪ Highly sensitive devices that detect magnetic fields surround the skull and detect minute changes in brain activity. ▪ MEG records the electrical activity of nerve cells just a few milliseconds after it occurs, which allows researchers to record brain activity at nearly the instant a stimulus is present. ▪ This is advantageous compared to PET and fMRI, which record responses only after a delay of several seconds.  Lesioning and Brain Stimulation o A number of methods have been developed that, in effect, shut down a portion of the brain to see how it affects behavior. o The oldest method based on this idea is brain lesioning, a technique in which researchers intentionally damage an area in the brain (a lesion is abnormal or damaged brain tissue). o Transcranial magnetic stimulation (TMS) is a procedure in which an electromagnetic pulse is delivered to a targeted region of the brain. ▪ The result is a temporary disruption of brain activity, analogous to the permanent disruption caused by a brain lesion. ▪ TMS can also be used to stimulate, rather than temporarily impair, a brain region. Psychological Science – Chapter 4: Sensation and Perception 4.1 Sensation and Perception at a Glance  Context plays an extremely important role in what people sense and perceive. For example, Joshua Bell, one of the world’s most talented violinists played at a subway station and very few people stopped to listen without realizing he is one of the best living violinists playing a $3.5 million violin. 25  Top-down processing occurs when prior knowledge and expectations guide what is perceived.  Bottom-up processing is the construction of a whole stimulus or concept from bits of raw sensory information.  The way we perceive the world is a combination of both top-down and bottom-up processing.  Parallel processing refers to the simultaneous use of top-down and bottom-up processing as we perceive and interpret the world. It is what allows us to attend to multiple features of what we sense. Perceiving the world, whether done form a bottom- up, top-down, or combined direction, requires attending to relevant features.  Attention and Perception o Selective attention involves focusing on one particular event or task. o Divided attention involves paying attention to several stimuli or tasks at once.  Inattentional blindness is a failure to notice clearly visible events or objects because attention is directed elsewhere. o For example, the dancing gorilla film. The audience is focused on watching what the students in the video are doing that they don’t notice a gorilla walk in and dance. o Inattentional blindness accounts for many common phenomena. For example, those who witness auto accidents or criminal behavior may offer faulty or incomplete testimony. This is not necessarily because they failed to remember, but because they did not even notice critical events. 26 4.2 The Visual System  How the Eye Gathers Light o “Light” refers to radiation that occupies a relatively narrow band of the electromagnetic spectrum. It travels in waves that vary in terms of two different properties: length and amplitude. o Wavelength refers to the distance between peaks of a wave. Differences in wavelength correspond to different colors on the electromagnetic spectrum. Long wavelengths correspond with the reddish colors and short wavelengths correspond with the bluish colors. o The amplitude (or height) of the peaks of a wave gives different experiences. Low-amplitude waves correspond with dim colors, and high-amplitude waves with bright colors. o We do not typically see pure coloration, rather, what we see is based on a mixture of wavelengths that vary by hue (colors of the spectrum), intensity (brightness), and saturation (colorfulness, or density).  The Structure of the Eye o The sclera is the white, outer surface of the eye. o The cornea is the clear layer that covers the front portion of the eye and also contributes to the eye’s ability to focus. o The pupil regulates the amount of light that enters by changing its size; it dilates to allow more light to enter and constricts to allow less light into the eye. o The iris is actually a round muscle that adjusts the size of the pupil; it also gives the eyes their characteristic color. o Behind the pupil is the lens, a clear structure that focuses light onto the back of the eye. o The rear portion of the eye consists of a layer of specialized receptors that convert light into a message that the brain can then interpret.  The Retina: From Light to Nerve Impulse o The retina lines the inner surface of the eye and consists of specialized receptors that absorb light and send signals related to the properties of light to the brain. o The specialized receptors of the retina are called photoreceptors. There are two general types: rods and cones, each corresponding to different characteristics of light. o Cones are photoreceptors that are sensitive to the different wavelength of light that we perceive as color. o The fovea is the central region of the retina that contains the highest concentration of cones. Its functioning explains why objects in our direct line of vision are the clearest and most colorful relative to objects in the periphery. o Rods are photoreceptors that occupy peripheral regions of the retina; they are highly sensitive under low light levels. o As we move away from the fovea, the concentration of cones decreases and the concentration of rods increase. o Dark adaptation is the process by which the rods and cones become increasingly sensitive to light under low levels of illumination. ▪ The complete process typically takes approximately 20 minutes, although most of the changes occur within the first 10 minutes. We do not see color at night or in darkness because rods do not detect color – rods are more active under low light levels than cones.  Each eye has an optic nerve, a cluster of neurons that gather sensory information, exit at the back of the eye, and connect with the brain. o Because it travels through the back of the eye, it creates an area on the retina with no rods or cones, called the optic disc. The result is a blind spot – a space in the retina that lacks photoreceptors. o The visual areas of the brain are able to “fill in” the missing information for us.  Common Vision Disorders o Nearsightedness occurs when the eyeball is slightly elongated, causing the image that the cornea and lens focus on to fall short of the retina. o Farsightedness occurs when the length of the eye is shorter than normal from front to back. In this case, the image is focused behind the retina.  The Visual Pathways to the Brain o The information contained in the cells that constitute the optic nerve travels to numerous areas of the brain. 27 o The first major destination is the optic chiasm, the point at which the optic nerves cross the midline of the brain. For each optic nerve, half of the nerve fibers travel to the same side of the brain, and half to the opposite side. They first connect with the visual area of the thalamus at a region called the lateral geniculate nucleus (LGN). o The LGN sends messages to the visual cortex, located in the occipital love, where the complex processes of visual perception begin. o The visual cortex makes sense of this information by first starting with a division of labor among specialized cells. One set of cells are referred to as feature detection cells; they respond selectively to simple and specific aspects of a stimulus, such as angles and edges. o From the visual cortex, information about shapes and contours is sent to other cortical areas. ▪ The ventral stream is a pathway extending from the visual cortex to the temporal lobe and is where object recognition occurs. ▪ The dorsal stream extends from the visual cortex to the parietal love of the cortex and is where depth and motion are perceived.  Despite the diverse ways that an object can be sensed, it is still perceived as the same object.  Perceptual constancy is the ability to perceive objects as having constant shape, size, and color despite changes in perspective. o Shape constancy allows us to judge the angle of the object relative to our position. o Color constancy allows us to recognize an objects color under varying levels of illumination. o Size constancy is based on judgments of how close an object is relative to one’s position as well as to the positions of other objects.  Facial Recognition and Perception o There is a region of the brain, located in the lower part of the temporal lobe that is specialized for facial recognition. o Prosopagnosia, or face blindness, a condition that results from specific genetic problems or damage to this area, resulting in failure to recognize people’s faces. People with these conditions can use non- facial characteristics to recognize people such as voice recognition.  Depth Perception o Binocular depth cues are distance cues that are based on the differing perspectives of both eyes. ▪ Convergence occurs when the eye muscles contract so that both eyes focus on a single object. This typically occurs for objects that are relatively close to you. o Retinal disparity (also called binocular disparity) is the difference in relative position of an object as seen by both eyes, which provides information to the brain about depth. ▪ Your brain relies on cues from each eye individually and from both eyes working in concert – that is, in stereo. Most primates, including humans, have stereoscopic vision, which results from overlapping visual fields. o Monocular cues are depth cues that we can perceive with only one eye. ▪ Accommodation takes place when the lens of your eye curves to allow you to focus on nearby objects.  Close one eye and focus on a nearby object, and then slightly change your focus to an object that is farther away; the lens changes shape again so the next object comes into focus. ▪ Motion parallax is another monocular depth cue; it is used when you or your surroundings are in motion.  For example, as you sit in a moving vehicle and look out of the passenger window, you will notice objects closer to you appear to move rapidly in the opposite direction of your travel. By comparison, far-off objects appear to move much more slowly, and in the same direction as your vehicle.  Color Perception o Color is not a characteristic of objects themselves, but rather an interpretation of these wavelengths by the visual system. o The trichromatic theory (or Young-Helmholtz theory) maintains that color vision is determined by three different cone types that are sensitive to short, medium, and long wavelengths of light. o A negative afterimage is the color you see after one color is removed, and it is opposite in color to the 30 the auditory cortex in the temporal lobe.  Sound localization is the process of identifying where sound comes from. 31 o It is handled by a midbrain structure called the inferior colliculus. o We localize sound in two ways: taking advantage of the slight time difference between a sound hitting both ears to estimate the direction, and by using differences in the intensity in which sound is heard by both ears – a phenomenon known as a sound shadow.  Theories of Pitch Perception o The place theory of hearing states that how we perceive pitch is based on the location (place) along the basilar membrane that sound stimulates. o The frequency theory states that the perception of pitch is related to the frequency at which the basilar membrane vibrates. ▪ A 70-Hz sound, at 70 cycles per second, stimulates the hair cells 70 times per second. Thus 70 nerve impulses per second travel from the auditory nerves to the brain, which interprets the sound frequency in terms of pitch. ▪ However, neurons cannot fire more than 1,000 times per second. Given this limit, we can still hear sounds exceeding 1,000 Hz due to the volley principle. A single neuron cannot fire more than 1,000 times per second, but a group of neurons could. ▪ According the volley principle, groups of neurons fire in alternating (hence the term “volley”) fashion. o The primary auditory cortex is a major perceptual center of the brain involved in perceiving what we hear. ▪ Cells within different areas across the auditory cortex respond to specific notes. For example, high musical notes are processed at one end of the auditory cortex, and progressively lower notes are heard as you move to the other end. ▪ The auditory cortex and surrounding areas are responsible for perceiving and interpreting sound.  Deafness o A conduction hearing loss results when any of the physical structures that conduct sound waves to the cochlea are damaged. o Sensorineural hearing results from damage to the cochlear hair cells (sensory) and the neurons composing the auditory nerve (neural). 4.4 Touch and the Chemical Senses  How We Perceive Touch o Sensitivity, or acuity, to touch varies across different regions of the body. o Haptics is the active, exploratory aspect of touch sensation and perception. ▪ Active touch involves feedback. For example, you can move your fingers over the surface of an object to identify whether any faults may be present. ▪ For some people, recognizing objects by haptics is hampered by damage to the somatosensory cortex, a condition called tactile agnosia. A person with this condition would struggle to identify common objects and even wooden blocks of common geometric shapes. o Kinesthesis is the sense of bodily motion and position. ▪ Receptors for kinesthesis reside in the muscles, joints, and tendons. They transmit information about movement and the position of your muscles, limbs, and joints to the brain.  Feeling Pain o Nociception is the activity of nerve pathways that respond to uncomfortable stimulation. 32 ▪ Skin, teeth, cornea, and internal organs contain nerve endings called nociceptors, which are receptors that initiate pain messages that travel to the central nervous system. ▪ Nociceptors come in varieties that respond to various types of stimuli. o Two types of nerve fibers transmit pain messages. Fast fibers register sharp, immediate pain. Slow fibers register chronic, dull pain. o The hypothalamus regulates arousal and emotional responses, which are part of the experience of pain. The other region, the somatosensory cortex, registers the pain sensations occurring over the entire surface of the body. o Pain varies from mild to severe and from acute (brief) to chronic. o The gate-control theory explains our experience of pain as an interaction between nerves that transmit pain messages and those that inhibit these messages. ▪ According to this theory, cells in the spinal cord regulate how much pain signaling reaches the brain.  Phantom limb sensations are frequently experienced by amputees, who report pain and other sensations coming from the absent limb. o A treatment for phantom pain involves the mirror box, which uses the reflection of the amputee’s existing limb, such as an arm and hand, to create the visual appearance of having both limbs. Amputees often find that watching themselves move and stretch the phantom hand, which is actually the mirror image of the real hand, results in significant decrease in discomfort.  The Chemical Senses: Taste and Smell o The chemical senses comprise a combination of both taste and smell. Although they are distinct sensory systems, both begin the sensory process with chemicals activating receptors on the tongue and mouth, as well as on the nose.  The Gustatory System: Taste o The gustatory system functions in the sensation and perception of taste. o Taste is adaptive in that it helps ensure that we nourish our bodies and avoid poisoning ourselves. o Receptors for taste are located in the visible, small bumps (papillae) that are distributed over the surface of the tongue. The papillae are lined with taste buds. o The primary tastes include salty, sweet, bitter, and sour. In addition, a fifth taste, called umami, has been identified. Umami is sometimes referred to as “savoriness” and is a Japanese word that refers to tastes associated with seaweed, the seasoning monosodium glutamate (MSG), and protein-rich foods such as milk and aged cheese. o Humans have approximately 10,000 taste buds but about 25% of the population have many times this number and are referred to as supertasters. They are especially sensitive to bitter tastes.  The Olfactory System: Smell o The olfactory system is involved in smell – the detection of airborne particles with specialized receptors located in the nose. o Smell works in concert with taste to give us the experience of flavor. It makes food enjoyable, but also helps us to identify harmful substances, helps us to recognize individuals, and can warn us of danger. o The sensation of smell begins with nasal airflow bringing in molecules that bind with receptors at the top of the nasal cavity. o The olfactory epithelium is a thin layer of cells that are lined by sensory receptors called cilia. o Cilia are tiny hair-like projections that contain specialized proteins that bind with the airborne molecules that enter the nasal cavity. They transmit messages to neurons that converge on the olfactory bulb, which serves as the brain’s central region for processing smell. The olfactory bulb connects with several regions of the brain through the olfactory tract, including the limbic system (emotion) as well as regions of the cortex where the subjective experience of pleasure (or disgust) occurs. o Despite the fact that humans have only 1,000 different types of odor receptors, we can detect approximately 10,000 different odors because odor molecules can stimulate several receptors simultaneously. It is the pattern of the stimulation, involving more than one receptor that gives rise to the experience of a particular smell.  Developing Preferences for Flavors o 80% of our information about food comes from olfaction. o Flavor perception is a subjective experience that is influenced by cultural experiences. 35 and tear on the body from the day’s activities. 36 o The preserve and protect hypothesis suggests that two more adaptive functions of sleep are preserving energy and protecting the organism from harm. ▪ To support this hypothesis, researchers note that the animals most vulnerable to predators sleep in safe hideaways and during the time of day when they are most susceptible. For humans and other visually oriented creatures, sleep occurs at night when it is dark and, therefore, when we would be at a disadvantage. Conversely, animals such as lions and bears rarely fall victim to predators, and they may sleep 15 hours per day.  Sleep deprivation occurs when an individual cannot or does not sleep. o Research on adolescents shows that for every hour of deprivation, predictable increases in physical illness, family problems, substance abuse, and academic problems occur. Sleep deprivation is also as dangerous as driving while mildly intoxicated and it is one of the most prevalent causes of fatal traffic accidents.  Sleep displacement occurs when an individual is prevented from sleeping at the normal time although she may be able to sleep earlier or later in the day than usual.  Jet lag is the discomfort a person feels when sleep cycles are out of synchronization with light and darkness.  Theories of Dreaming o The Psychoanalytic Approach ▪ Sigmund Freud viewed dreams as an unconscious expression of wish fulfillment. ▪ Freud believed that humans are motivated by primal urges, with sex and aggression being the most dominant. ▪ Since giving into these urges are usually impractical, we suppress them and keep them outside of our conscious awareness. When we sleep, we lose the power to suppress our urges and in turn, these drives create the vivid imagery of dreams. ▪ The manifest content is the images and storylines that we dream about.  In many cases, they actually involve sexuality and aggression. ▪ The latent content is the actual symbolic meaning of a dream built on suppressed sexual or aggressive urges. ▪ Because the true meaning of the dream is latent, Freud advocated dream work, the recording and interpreting of dreams. o The activation-synthesis hypothesis suggests that dreams arise from brain activity originating from bursts of excitatory messages from the brainstem. ▪ The pons, located in the brain stem, sends excitatory messages through the thalamus to ▪ The brain stem actions initiate the activation component of the model. ▪ The synthesis component arises as the brain tries to make sense of all the images. ▪ Because these images are randomly activated, the storyline of a dream typically seems disjointed and bizarre.  The problem-solving theory of dreaming is the theory that thoughts and concerns are continuous from waking to sleeping, and that dreams may function to facilitate finding solutions to problems encountered while awake.  Disorders and Problems With Sleep o Insomnia is a disorder characterized by an extreme lack of sleep. ▪ Insomnia affects approximately 10% of the U.S. population. ▪ Onset insomnia occurs when a person has difficulty falling asleep (30 minutes or more). ▪ Maintenance insomnia occurs when an individual cannot easily return to sleep after waking in the night. ▪ Terminal insomnia is a situation in which a person wakes up too early – sometimes hours too early – and cannot return to sleep. ▪ Primary insomnia refers to cases that arise from an internal source and are not the result of another disorder. ▪ Secondary insomnia are the result of other disorders, such as depression, physical problems such as recovery from back surgery, or use of substances ranging from caffeine and nicotine to illegal drugs such as marijuana, ecstasy, or cocaine. o Nightmares are particularly vivid and disturbing dreams that occur during REM sleep. o Night terrors are intense bouts of panic and arousal that awaken the individual, typically in a heightened emotional state. 37 ▪ Unlike nightmares, night terrors are not dreams. These episodes occur during NREM sleep, and the majority of eople who experience them typically do not recall any specific dream content. They are more common in young children than in adults. o Movement Disturbances ▪ Restless legs syndrome is a persistent feeling of discomfort in the legs and the urge to continuously shift them into different positions. ▪ Somnambulism, or sleepwalking, is a disorder that involves wandering and performing other activities while asleep.  It is more prevalent during childhood and Is not necessarily indicative of any type of sleep or emotional disturbance, although it may put people in harm’s way.  People who sleepwalk are not acting out dreams, and they typically do not remember the episode. o Sleep apnea is a disorder characterized by the temporary inability to breathe during sleep. ▪ This condition appears to be most common among overweight and obese individuals, and it is roughly twice as prevalent among men as among women. o Narcolepsy is a disorder in which a person experiences extreme daytime sleepiness and even sleep attacks. ▪ Narcolepsy differs from more typical sleep in that it may only last a few minutes or more. People with a normal sleep pattern generally reach REM stage after more than an hour of sleep, but a person experiencing narcolepsy is likely to go almost immediately from waking to REM sleep. Also, because REM sleep is associated with dreaming, people often report vivid dream-like images even if they did not fully fall asleep. ▪ Scientists have investigated a hormone called orexin that functions to maintain wakefulness. Individuals with narcolepsy have fewer brain cells that produce orexin, resulting in greater difficulty maintaining wakefulness. o Sleep state misperception (SSM) is a condition in which a person underestimates her amount of sleep on a regular basis. ▪ People experiencing SSM are sometimes said to have paradoxical insomnia – they believe they cannot sleep enough, but there is no physiological or medical evidence to support that belief. o Positive sleep state misperception occurs when individuals regularly overestimate their sleep. o People often turn to drugs to help them sleep such as barbiturates and benzodiazepines. However, people quickly developed tolerance to these agents. Benzodiazepines are generally safer than barbiturates, but the risk of dependence and worsening sleep problems makes them suitable only for short-term use – generally for a week or two. 5.2 Altered States of Consciousness: Hypnosis, Meditation, and Disorders of Consciousness  Hypnosis is a procedure of inducing a heightened state of suggestibility. o Hypnotic suggestions generally are most effective when they fall into one of three categories: ▪ Ideomotor suggestions are related to specific actions that could be performed, such as adopting a specific position. ▪ Challenge suggestions indicate actions that are not to be performed, so that the subject appears to lose the ability to perform an action. ▪ Cognitive-perceptual suggestions are to remember or forget, or to experience altered perceptions such as reduced pain sensations.  Theories of Hypnosis o The word hypnosis comes from the Greek hypno, meaning, “sleep.” Scientific research tells us that hypnosis is nothing like sleep. For example, it can occur during periods of high alertness – including during physical exercise. o Dissociation theory explains hypnosis as a unique state in which consciousness is divided into two parts: an observer and a hidden observer. ▪ For example, when you first learn to drive a car, it took every bit of your conscious awareness to focus on the correct movements – you were a single, highly focused observer of your actions. After practicing for a long time, you could do it automatically while you observed and paid attention to something else. ▪ Although we call the familiar behavior automatic, there is still a hidden observer – that is, a part of you that is paying attention to the task. ▪ According to dissociation theory, hypnosis splits awareness in a similar way. At one level, the 40 Develops slowly Low Hallucinogens: LSD, psilocybin, DMT, ketamine Major distortion of sensory and perceptual experiences Increase serotonin activity Blocks glutamate receptors Develop s slowly Very low 41 Fear, panic, paranoia Opiates: heroin Intense euphoria, pain relief Stimulate endorphin receptors Develop s quickly Very high Sedatives: barbiturates, benzodiazepin es Drowsiness, relaxation, sleep Increase GABA activity Develops quickly High Alcohol Euphoria, relaxation, lowered inhibitions Primarily facilitates GABA activity; also stimulates endorphin and dopamine receptors Develop s graduall y Moderate to high  Psychoactive drugs are substances that affect thinking, behavior, perception, and emotion. o Drugs are categorized based on their effects on the nervous system. They can speed up the nervous system, slow it down, stimulate its pleasure centers, or distort how it processes the world.  Illicit drugs refer to those drugs whose manufacture, sale, and possession are illegal.  Stimulants are a category of drugs that speed up the nervous system, typically enhancing wakefulness and alertness. o Cocaine, one of the most commonly abused stimulants, is synthesized from cocoa leaves. They can be taken as leaves, snorted, and crack cocaine can be smoked in a pipe. o Amphetamines, another group of stimulants, come in a variety of forms. Some are prescription drugs typically prescribed for attention-deficit/hyperactivity disorder (ADHD) and narcolepsy. o Methamphetamine is another abused stimulant. It may be more potent than cocaine when it comes to addictive potential and is notorious for causing significant neurological as well as external physical problems. o Stimulants such as cocaine and methamphetamine affect neural activity in the reward centers of the brain. ▪ Cocaine blocks reuptake of dopamine by binding to presynaptic terminals, allowing excess amounts of this neurotransmitter to remain in the synapse and continue binding with postsynaptic receptors. ▪ Methamphetamine increases presynaptic release of dopamine and norepinephrine, and also slows their reuptake. o Ecstasy (MDMA) is typically classified as a stimulant, but also has hallucinogenic effects. ▪ Ecstasy heightens physical sensations and is known to increase social bonding and compassion among those who are under its influence.  Hallucinogenic drugs are substances that produce perceptual distortions. o Commonly used hallucinogens include LSD (lysergic acid diethylamide), which is a laboratory-made (synthetic) drug. o Hallucinogenic substances can also occur in nature, such as psilocybin (a mushroom) and mescaline (derived from the peyote cactus). 42 o Hallucinogens can have very long-lasting effects – more than 12 hours for LSD, for example, and may also elicit powerful emotional experiences that range from extreme euphoria to fear, panic, and paranoia. o The two most common hallucinogens, LSD and psilocybin, both act on the transmission of serotonin. o Short-acting hallucinogens have become increasingly popular for recreational use. Examples of such hallucinogens include ketamine and DMT (dimethyltryptamine), which last for about an hour. 45 o Stimulus generalization is a process in which a response that originally occurs to a specific stimulus also occurs to different, though similar stimuli. ▪ In Pavlov’s experiment, dogs salivated not just to the original tone (CS), but also to very similar tones. ▪ Generalization allows for flexibility in learned behaviors, however it is possible for behavior to be too flexible. Salivating in response to any sound would be wasteful because not every sound correctly predicts food. Thus, Pavlov’s dogs also showed discrimination. o Discrimination occurs when an organism learns to respond to one original stimulus but not to new stimuli that may be similar to the original stimulus.  Conditioned emotional responses consist of emotional and physiological responses that develop to a specific object or situation. o Watson and Rayner conducted one of their first studies with an 11-month-old child known as Albert B. (also referred to as “Little Albert”). Albert was not afraid of rats at first, but the presence of the rat was paired with the striking of a steel bar with a hammer, startling Albert. Eventually, he showed a conditioned emotional response just to the rat, as well as other objects that resembled it. o Psychopathy is a disorder that causes people to disregard the feelings for others. When shown pictures of faces that had been paired with pain, their emotional centers remained quiet and overall they did not seem to mind. o A healthy fear response is important for survival, but not all situations or objects are equally dangerous. Snakes and heights should probably elicit more fear and caution than butterflies or freshly mown grass. In fact, fearing snakes is very common, which makes it tempting to conclude that we have an instinct to fear them. In reality, young primates tend to be quite curious about, or at least indifferent, to snakes, so this fear is most likely the product of learning rather than instinct. o Researchers found that conditioned arousal to guns among participants was less than that to snake photos, and comparable to that of harmless flowers. o Preparedness refers to the biological predisposition to rapidly learn a response to a particular class of stimuli , such as the finding that we learn to fear snakes more readily than either flowers or guns. ▪ Over time, humans have evolved a strong predisposition to fear an animal that has a long history of causing severe injury or death. Guns are relatively new in our species’ history.  A conditioned taste aversion is the acquired dislike or disgust of a food or drink because it was paired with illness. o This may develop in a variety of ways such as through illness associated with food poisoning, the flu, medical procedures, or excessive intoxications. When we develop aversion to a particular food, the relationship typically involves the flavor of the food and nausea, rather than the food and any stimulus that may have been present during conditioning. o Latent inhibition occurs when frequent experience with a stimulus before it is paired with a US makes it less likely that conditioning will occur after a single episode of illness.  Drug Use and Tolerance o Classical conditioning accounts for some drug-related phenomena, such as cravings and tolerance. Cues that accompany drug use can become conditioned stimuli that elicit cravings. For example, a cigarette lighter, the smell of tobacco smoke, or the presence of another smoker could elicit cravings in people who smoke. o Conditioned drug tolerance involves physiological responses in preparation for drug administration. For example, using a drug in a different environment could cause the body to be unprepared for delivery of the drug.  Sexual Arousal o Sexual arousal and reproductive physiology can also be influenced by classical conditioning. o A fetish involves sexual attraction and fixation on an object. A conditioned sexual fetish can form if there is an association between the object (the CS) and sexual counters (the US). o The conditioned physiological changes associated with drug tolerance and sexual responses can occur below the level of awareness. It appears that certain types of conditioning involve relatively basic, if not minimal, brain functioning.  Conditioning and Traumatic Brain Injury o Researchers have shown that people who have minimal brain function can still be conditioned. Although patients may not be able to communicate about the conditioning experience to the researchers, they can show association by a simple conditioned eye blink response that is elicited by the sound of a tone.  The Paradox of “Diet” Beverages o The taste of a candy bar is a conditioned stimulus (CS) that tells the body that a large amount of calories (the US) is son to arrive in the gut. This relationship is an important one for the body to learn, 46 as it helps maintain and energy balance – eventually your body tells you it is time to stop eating sweets and switch to something else. o Artificially sweetened beverages disrupt this relationship between the sugary sweet CS and high- calorie food US. The artificially sweetened taste of a diet soda is not followed by a high dose of calories that your body “expects.” As a 47 result, it continues to send out hunger messages: Your gut “tells” you to make up for the calories by opening up a bag of cookies or potato chips. o This linkage may very well help explain why, overall, artificially sweetened beverages do not promote weight loss. 6.2 Operant Conditioning: Learning Through Consequences Major Differences Between Classical and Operant Conditioning (Table 6.1) Classical Conditioning Operant Conditioning Target response is… Automatic Voluntary Reinforcement is… Present regardless of whether a response occurs A consequence of the behavior Behavior mostly depends on… Reflexive and physiological responses Skeletal muscles  Operant conditioning is a type of learning in which behavior is influenced by consequences. o The term operant is used because the individual operates on the environment before consequences can occur. o In contrast to classical conditioning, which typically affects reflexive responses, operant conditioning involves voluntary actions such as speaking or listening, starting and stopping an activity, and moving toward or away from something.  Processes of Operant Conditioning o Contingency means that a consequence depends upon an action. This is important to understanding operant conditioning. 50  Negative punishment occurs when a behavior decreases because it removes or diminishes a particular stimulus. o For example, a parent who “grounds” a child does so because this action removes something of value to the child. Comparing Extinction, Generalization, and Discrimination in Classical and Operant Conditioning (Table 6.3) Process Classical Conditioning Operant Conditioning Extinction A CS is presented without a US until the CR no longer occurs Responding gradually ceases if reinforcement is no longer available. Generalizati o n Discriminati o n A different CS that resembles the original CS used during acquisition that elicits a CR. A CR does not occur in response to a different CS that resembles the original CS. Responding occurs to a stimulus that resembles the original discriminative stimulus used during learning. There is no response to a stimulus that resembles the original discriminative stimulus used during learning.  Extinction refers to the weakening of an operant response when reinforcement is no longer available.  A discriminative stimulus is a cue or event that indicates that a response, if made, will be reinforced. o Stimulus control is when a discriminative stimulus reliably elicits a specific response.  In operant conditioning, generalization occurs when an operant response takes place to a new stimulus that is similar to the stimulus present during original learning.  Discrimination occurs when an operant response is made to one stimulus but not to another, even similar stimulus.  Applications of Operant Conditioning o Shaping is a procedure in which a specific operant response is created by reinforcing successive approximations of that response. o Schedules of reinforcement are rules that determine when reinforcement is available. o Continuous reinforcement is when every response made results in reinforcement. o Partial (intermittent) reinforcement is when only a certain number of responses are rewarded, or a certain amount of time must pass before reinforcement is available. ▪ In a fixed-ratio schedule, reinforcement is delivered after a specific number of responses have been completed. ▪ In a variable-ratio schedule, the number of responses required to receive reinforcement varies according to an average. ▪ A fixed-interval schedule reinforces the first response occurring after a set amount of time passes. ▪ In a variable-interval schedule, the first response is reinforced following a variable amount of time. o The partial reinforcement effect refers to a phenomenon in which organisms have been conditioned under partial reinforcement resists extinction longer than those conditioned under continuous reinforcement.  Applying Punishment o People tend to be more sensitive to the unpleasantness of punishment than they are to the pleasures of reward. o People often report spanking their children because it works; however psychologists tend not to advocate this behavior as it may have major side effects. Punishment Tends to Be Most Effective When Certain Principles Are Followed (Table 6.4) Severity Should be proportional to offense. A small fine is suitable for parking illegally or littering, but inappropriate for someone who commits assault. Initial punishment level The initial level of punishment tends to be sufficiently strong to reduce the likelihood of the offense occurring again. Contiguity Punishment is most effective when it occurs immediately after the behavior. Many convicted criminals are not sentenced until many months after they have committed an offense. Children are given detention that may not being until hours later. Long delays in punishment are known to reduce its effectiveness. Consistency Punishment should be administered consistently. A parent who only occasionally punishes a teenager for breaking her curfew will probably have less success in curbing the behavior than a parent who uses punishment consistently. Show alternatives Punishment is more successful, and side effects are reduced, if the individual is clear on how reinforcement can be obtained by engaging in appropriate behaviors. 51 6.3 Cognitive and Observational Learning  Latent learning is learning that is not immediately expressed by a response until the organism is reinforced for doing so.  Rats in a maze possess a cognitive map of their environment. Once they know the route, they can go through it at a much faster rate the next time, especially if the behavior is reinforced.  Successful Long-Term Learning and Desirable Difficulties o There are at least three habits people fall into when trying to learn new behaviors: ▪ We want clarity about what to learn or do. ▪ We want very noticeable results. ▪ We want it all to happen very fast. o Organization Versus Rearrangement ▪ Students benefit from reorganizing information from their notes and readings. Students with organized notes were compared to those with scrambled notes. ▪ The results were that scrambled notes led to more effortful studying and, therefore, more meaningful learning. o Total Time Versus Distributed Practice ▪ Research suggests that studying little by little over a long period of time is more effective than cramming everything all at once. For example, distributing 4 hours of study over four separate 1-hour sessions has been proven to be much better than cramming for 4 hours straight. o Creating Desirable Difficulties ▪ When you are trying to learn something, such as a song on an instrument, it may be more effective to learn it section by section, rather than starting from the beginning each time. ▪ When learning definitions on flash cards, it might be a good idea to shuffle the deck from time to time.  Observational learning involves changes in behavior and knowledge that result from watching others.  Processes Supporting Observational Learning o Albert Bandura identified four processes involved in observational learning: attention to the act or behavior, memory for it, the ability to reproduce it, and the motivation to do so. o Without any of these processes, observational learning would be unlikely – or at least would result in a poor rendition.  Imitation is recreating a motor behavior or expression, often to accomplish a specific goal. 52 o From a very young age, infants imitate the facial expressions of adults. 55 participants are to report the corresponding line – bottom, middle, or top. Under these conditions, participants still report only three or four of the letters, but they can report them from any randomly selected line. Because the tone comes after the screen goes blank, the only way the participants could get the letters right is if they recalled them from memory. Thus, it was argued that iconic memory could hold all 12 letters as a mental image. o Echoic memory is, for example, when someone asks you a question and you say, “What?” only to realize that you still have the person’s voice in echoic memory – and suddenly say “Oh!” and answer the question before they repeat the question.  Distinguishing Short-Term From Long-Term Memory Stores o Short-term memory (STM) is a memory store with limited capacity and duration (less than a minute). o Long-term memory (LTM) is a memory store that holds information for extended periods of time, if not permanently. o If your class was told to study a list of 15 words and then immediately tried to recall the words, the serial position effect would occur. o The serial position effect is that in general, most people will recall the first few items from a list and the last few items, but only an item or two from the middle. o Proactive interference is when the first information learned occupies memory, leaving fewer resources left to remember the newer information. Yet, we also remember the last few items because they still reside in our STM – a pattern referred to as the recency effect. o The last few items on the list create retroactive interference. o Retroactive interference is when the most recently learned information overshadows some older memories that have not yet made it into long-term memory.  The Working Memory Model: An Active STM System o Rehearsal is when you repeat information until you do not need to remember it anymore. o Working memory is a model of short-term remembering that includes a combination of memory components that can temporarily store small amounts of information for a short period of time. o The working memory model for short-term remembering can be subdivided into three storage components. ▪ The phonological loop is a storage component of working memory that relies on rehearsal and stores information as sounds, or an auditory code. ▪ The visuospatial sketchpad is a storage component of working memory that maintains visual images and spatial layouts in a visuospatial code. ▪ The episodic buffer is a storage component of working memory that combines the images and sounds from the other two components into coherent, story-like episodes. o Working memory also includes one component that is not primarily used for storing information. ▪ The central executive is the control center of working memory; it coordinates attention and the exchange of information among the three storage components. ▪ It does so by seeking out what is relevant to the person’s goals, interests, and prior knowledge. ▪ For example, when you see a series of letters from a familiar alphabet, it is easy to remember the letters by rehearsing them in the phonological loop. ▪ How much and how long someone can remember information is affected by the specific information that is being remembered.  The Magical Number 7 o STM can rehearse only seven units of information at once before forgetting something. o Whenever possible, we expand our memory capacity by chunking. o Chunking is when you organize smaller units of information into larger, more meaningful units. ▪ For example, when you memorize someone’s telephone number, you memorize the numbers in groups of 3 or 4.  The Phonological Loop o The word-length effect suggests that people remember more one-syllable words than four- or five-syllable words. o The Brown-Peterson test is a technique for measuring the duration of working memory. It relies on two main elements – meaningless stimuli and interference. ▪ First, participants read a trigram (unpronounceable series of three letters). Then, they read a three-digit number, and they must count backward (by threes) from the number to interfere with rehearsal (to make sure they cannot repeat the trigram to themselves). They do this until the experimenter says to stop, and at this point, the participants are to report the trigram. 56 ▪ Most of the forgetting tends to take place within 15 to 18 seconds. Thus, the duration of the phonological memory is approximately 15 seconds.  The Visuospatial Sketchpad o Feature binding is the process of combining visual features into a single unit. o After visual feature binding, visuospatial memory can accurately retain approximately four whole objects, regardless of how many individual features one can find on those objects. This may be evidence of a second magical number – four. o For example, if you are driving, you probably would not look at a car in front of you and remember images if red, shiny, and smooth. Instead, you would simply have these features bound together in the image of the car, and you would be able to keep track of three or four more such images without much problem.  The Episodic Buffer o The episodic buffer is the most recently hypothesized working memory system and researchers are still examining evidence for and against it. o The episodic buffer seems to hold 7 to 10 pieces of information, which may be combined with other memory stores. o This aspect of its operation can be demonstrated by comparing memory for prose (words strung into sentences) to memory for unrelated words. When people are asked to read and remember meaningful prose, they usually remember 7 to 10 more words than when reading a random list of unrelated words. o Some portion of working memory is able to connect the prose with LTM (knowledge) to increase memory capacity. Because the phonological loop is not doing the binding, some psychologists have proposed that this phenomenon may demonstrate the episodic buffer at work.  Long-Term Memory Systems: Declarative and Nondeclarative Memories o Declarative memories are memories that we are consciously aware of and can be verbalized, including facts about the world and one’s own personal experiences. o Nondeclarative memories include actions or behaviors that you can remember and perform without awareness. ▪ Procedural memories are patterns of muscle movements (motor memory), such as how to walk, play piano, or shift gears while driving. ▪ Classical conditioning is another type of nondeclarative memory as people can be classically conditioned without awareness. o Declarative memory comes in two varieties. ▪ Episodic memories are declarative memories for personal experiences that seem to be organized around “episodes” and are recalled from a first-person (“I” or “my”) perspective. ▪ Semantive memories are declarative memories that include facts about the world. ▪ Semantic memory is, for example, your knowledge of what a bike is, whereas episodic memory is the memory of when you first (or last) rode a bike, a specific ride that was enjoyable to you, or the last time you rode into a fence.  The Cognitive Neuroscience of Memory o With the behavioral and cognitive aspects of memory, the biopsychosocial model reminds us that everything involves a biological component as well. o Psychologists also look at how the nervous system changes with the formation of new memories, and they examine which areas of the brain are actively involved in remembering.  Memory at the Neural Level o At the neural level, memory formation beings with long-term potentiation. This process underlies the permanent changes that occur across numerous brain cells as memories are forming, strengthening, and being stored. o Long-term potentiation (LTP) means that there is an enduring increase in connectivity and transmission of neural signals between nerve cells that fire together. ▪ In the process of classical conditioning, after two or three pairings of an unconditioned stimulus, a neutral stimulus, and an unconditioned response, the neurons that respond to each one develop a history of firing together. This simultaneous activation provides the opportunity for LTP to being, representing the first stages of memory. o Long-term potentiation is far from permanent, so it might not account for memories that may last days, weeks, or even years. o Consolidation, the process of converting short-term memories into long-term memories in the brain. o Cellular consolidation is the process in which, when LTP continues long enough, neurons adapt to make changes more permanent. 57  Memory at the Cortical Level 60  The Forgetting Curve: How Soon We Forget… o Ebbinghaus’s forgetting curve showed that most forgetting occurs right away, and that the rate of forgetting eventually slows to the point where one does not seem to forget at all. 61 o Bahrick’s long-term forgetting curve indicated the rate at which adults forgot the foreign language they took in high school. Compared to new graduates, those tested two to three years later forgot much of what they learned. After that, however, test scores stabilized.  Mnemonics: Improving Your Memory Skills o Mnemonics are techniques that are intended to improve memory for specific information. o An acronym is a pronounceable word whose letters represent the initials of an important phrase or set of items. ▪ For example, “scuba” came into being with the invention of the self-contained underwater breathing apparatus. o The first letter technique uses the first letters of a set of items to spell out words that form a sentence. ▪ It is like an acronym, but it tends to be used when the first-letters do not spell a pronounceable word. ▪ For example, “Every Good Boy Deserves Fudge” is used for the five lines on the treble clef in musical notation. It even has an acronym to go along with it: “FACE” represents the four spaces between E, G, B, D, and F. o These types of mnemonic techniques work by chunking – that is, by organizing the information into a pattern that makes more sense than the original information. o Acronyms have a meaning of their own, so the learner gets the benefit of both elaborative rehearsal and deeper processing.  Dual coding occurs when information is stored in more than one form. o For example, a verbal description and a visual image, or a description and a sound – and it regularly produces stronger memories than the use of one form alone. o Most children growing up in the United States learned the alphabet with the help of a song. In fact, even adults still find themselves humming portions of that song when necessary. o The simplest explanation for the dual-coding advantage is that twice as much information is stored.  These mnemonics also make use of levels of processing by requiring elaboration with the images, and the elaboration seems to be the most important component in ensuring the effectiveness of memory.  The method of loci is a mnemonic that connects words to be remembered to locations along a familiar path. o To use the method of loci, one must first imagine a route that has landmarks or easily identifiable spaces – for example, the things you pass on your way from your home to a friend’s house. Once the path is identified, the learner takes a moment to visually relate the first word on the list to the first location encountered.  Desirable difficulties make studying slower and more effortful, but result in better overall remembering. They include spacing out your studying rather than cramming, and studying material and varying orders.  The testing effect is the finding that taking practice tests can improve exam performance, even without additional studying. 62 7.3 Constructing and Reconstructing Memories  How Memories Are Organized and Constructed o When we read a book or watch a movie, we tend to remember the basic plot for a very long time (may be referred to as the gist of the story) and that impacts us much more than the characters’ names, which are often just details. o Much of the way we store memories depends on our tendency to remember the gist of things.  The Schema: An Active Organization Process o A schema is an organized cluster of memories that constitutes one’s knowledge about events, objects, and ideas. ▪ For example, the event could be gathering clothes and going to the laundromat. The object could be what clothes are and what detergent is. The idea could be why clean clothes are desirable. This may describe your typical laundry schema – your personal collection of concepts and memories. ▪ When your schema is activated, you are prepared to make sense of a vague description of the memory. That is, if you were presented with a paragraph describing how you arrange things into different groups, how the groups may be different, that you may need to go somewhere else due to lack of facilities, etc., it may not make much sense to you. However once you are informed that it is about doing laundry, the paragraph will make much more sense when you read through it again. o Schemas are involved in all three stages of memory: They guide what we attend to during encoding, organize stored memories, and serve as cues when it comes time to retrieve information. o Schemas appear to be products of culture and experience. o We all have schemas about ourselves, and they are referred to as self-schemas. They may contribute to psychological problems. ▪ For example, someone with a very negative self-schema will pay attention to things that are consistent with the depressive symptoms, and will be more likely to recall events and feelings that are consistent with this schema. Thus, the schema contributes to a pattern of thinking and focusing on negative thoughts.  Constructing Memories o Constructive memory is a process by which we first recall a generalized schema and then add in specific details. o Schemas tell us what to expect in a situation as well as what is relevant and important. o In a schema we are familiar with, objects typically found in environment are all schema consistent. Objects that are unusual and not a part of your schema are schema inconsistent. o Schemas can affect our memory in two ways: ▪ Organization. When we encounter a new situation, some objects and events will undoubtedly fit our schemas (i.e., our expectations) better than others. When the new information makes sense – that is, when it fits our schema – it can be easier to recall, yet it may be more difficult to recognize or report the exact details. 65 o Recovered memories are memories of a traumatic event that are suddenly recovered after blocking the memory of that event for a long time, often many years. o The idea that we suppress traumatic memories is popularly known as repression from Freudian psychoanalysis. o The worse effects of false remembering individuals have been the well-documented occurrence of false recovered memories. People can be negatively affected by recovered memories that did not actually happen. o The recovered memory controversy is a heated debate among psychologists about the validity of recovered memories. ▪ For example, in the early 1990s, Beth Rutherford sought the help of her church counselor to deal with personal issues. She became convinced that her father raped her and when she became pregnant, he forced her to have an abortion. This negatively affected her family, as well as the reputation of her father. When a medical investigation was finally conducted, absolutely no evidence was found that Beth had ever been raped or that she had ever been pregnant. o Most memory recovery techniques are based on the same techniques that cognitive psychologists use to create false memories, especially imagery. Psychological Science – Chapter 8: Thought and Language 8.1 The Organization of Knowledge  A concept is the mental representation of an object, event, or idea. o There are very few independent concepts. You do not have just one concept for chair, table, or sofa. Each of these concepts can be divided into smaller groups with more precise labels such as arm chair or coffee table. Similarly, all of these items can be lumped together as furniture.  Categories refer to these clusters of interrelated concepts. o We form these groups using a process called categorization.  Classical categorization is the theory that claims that objects or events are categorized according to a certain set of rules or by a specific set of features. o Graded membership is the observation that some concepts appear to make better category members than others. 66 o Psychologists have researched classical categorization using a behavioral measure known as the sentence- verification technique, where volunteers wait for a sentence to appear in front of them on a computer screen and 67 respond as fast as they can with a yes or no answer to statements such as A sparrow is a bird, or, A penguin is a bird. In most cases, subjects almost always answer “yes” faster to sparrow than to penguin. While both are equally good fits for the definition, this occurs because sparrows are somehow more bird-like than penguins.  Prototypes: Categorization by Comparison o Prototypes are mental representations of an average category member. ▪ For example, given a robin, a sparrow, and a blue jay, your prototypical bird would look something like a mixture or the average of all three. o If you encounter a little creature you have never seen before and its basic shape resembles your prototype of a bird, you may classify the creature as a bird. o The main advantage of prototypes is that they help explain why some category members make better examples than others. Ostriches are birds just as much as blue jays, but they do not resemble the rest of the family very well. In other words, blue jays are closer to the prototypical bird.  Networks and Hierarchies  o A semantic network is an interconnected set of nodes (or concepts) and the links that join them to form a category. o A Semantic Network Diagram for the Category “Animal” (Figure 8.3) o Nodes are circles that represent concepts, and links connect them together to represent the structure of a category as well as the relationships among different categories. o Figure 8.3 is arranged in a hierarchy – that is, it consists of a structure moving from general to very specific. This organization helps us understand how categories work in daily thought and language by identifying the basic level category, which is located in the middle row of the diagram (where the birds and fish are). ▪ Basic level categories are the terms used most often in conversation. ▪ They are the easiest to pronounce. ▪ They are the level at which prototypes exist. ▪ They are the level at which most thinking occurs.  Priming and Semantic Networks o Priming is the activation of individual concepts in long-term memory. o Psychologists can test for priming through reaction time measures such as the sentence-verification task or through a method called the lexical decision task. ▪ A volunteer sits at a computer and stares at a focal point. Next, a string of letters flashes on the screen. The volunteer responds yes or no as quickly as possible to indicate whether the letters spell a word. Using this method, a volunteer should respond faster that “apple” is a word if it follows the word “fruit” than if it follows the word “bus.” ▪ Average response times were also faster when the holiday-themed words were congruent (in season). For example, words such as “nutcracker” and “reindeer” showed priming effects during December.  Culture and Categories o The human brain is wired to perceive similarities and differences, and the end result of this tendency is to categorize items based on these comparisons. o Our natural tendency to do so interacts with our cultural experiences; how we categorize objects depends to a great extent on what we have learned about those objects from others in our culture. 70 (satisficers).  Problem solving means accomplishing a goal when the solution or the path to the solution is not clear. 71  States and Stages o The initial state describes what the condition is at the outset of the problem. o The goal state describes what you need or desire as an outcome. o Obstacles are things that slow or prevent progress toward the goal state. o Operators are techniques we use to overcome the obstacles to reach the goal state. o A well-defined problem is a problem that has a clear initial state and goal state. ▪ For example, the initial state, “I’m cold,” has the operator, “Put on a sweater,” and so the goal state, “I’m comfortable,” is achieved. o An ill-defined problem is a problem that may be lacking definition in one or more ways, such as an ambiguous initial state or a lack of familiar operators. ▪ For example, the initial state, “I need to think of a topic for my term paper,” has the operator, “Flip through your favorite chapter in the textbook to find what interests you,” and so the goal state, “I’m going to write about culture and language,” is achieved.  Problem-Solving Strategies and Techniques o Algorithms are problem-solving strategies based on a series of rules. ▪ They are very logical and follow a set of steps, usually in a preset order. Computers are very good at using algorithms because they can follow a preprogrammed set of steps and perform thousands of operations every second. ▪ Humans are not always so careful and tend to rely on intuition to find operators and solutions that “just seem right.” o Heuristics are problem-solving strategies that stem from prior experiences and provide an educated guess as to what is the most likely solution. ▪ For example if you were deciding whether you would like to accept a dinner invitation, the intuitive approach (accept it) usually makes the most sense.  Cognitive Obstacles o A mental set is a cognitive obstacle that occurs when an individual attempts to apply a routine solution to what is actually a new type of problem. ▪ For example, The Five Daughter Problem: Maria’s father has five daughters: Lala, Lela, Lila, and Lola. What is the fifth daughter’s name? ▪ Your mental set may have caused you to believe the answer is Lula, but it is actually Maria. o Functional fixedness occurs when an individual identifies a potential operator, but can think of only its most obvious function.  Representativeness and Availability o Conjunction fallacy is the mistaken belief that finding a specific member in two overlapping categories (i.e., a member of the conjunction of two categories) is more likely than finding any member of one of the larger, general categories. o Representativeness heuristic is making judgments of likelihood based on how well an example represents a specific category. o The availability heuristic entails estimating the frequency of an event based on how easily examples of it come to mind. ▪ In other words, we assume that if examples are readily available, then they must be frequent. ▪ For example, most of us can think of examples of police brutality, kidnapping, and terrorist attacks – these are events that easily come to mind. However, we are also likely to overestimate the risks of each of these events, in part because it is easier to think of examples of these events than to think of all of the times they did not occur.  The anchoring effect occurs when an individual attempts to solve a problem involving numbers and uses previous knowledge to keep (i.e., anchor) the response within a limited range. o For example, “When was George Washington elected president?” Participants would reply with thoughts such as, “The U.S. declared independence in 1776 and it probably took a few years to elect a president, so Washington was elected in… 1789.” Thus, the signing of the Declaration of Independence in 1776 serves as the anchor for Washington’s election.  Humans have bounded rationality. We may be rational up to a point, but then heuristic thinking takes over. Use of heuristics leaves us open to biases and potentially costly mistakes.  A benefit of heuristic thinking is that, knowing people are susceptible to errors can help us to be better critical thinkers, allowing us to spend time evaluating our solutions, judgments, and decisions. 72  Belief perseverance occurs when an individual believes he or she has the solution to the problem or the correct answer for a question and accepts only evidence that will confirm those beliefs. o For example, a dealer removes cards from a box and counts to make sure they are all present. At first he comes up with 51 cards, then on the second try, he gets 52 – the correct amount. He proceeds to carry on with the game. o The dealer did not consider that the 52 may have been a miscount, which was shaded by his knowledge that there should be 52 cards in a deck.  Confirmation bias occurs when an individual searches for only evidence that will confirm his or her beliefs instead of evidence that might disconfirm them. 8.3 Language and Communication  Language is a form of communication that involves the use of spoken, written, or gestural symbols that are combined in a rule-based form.  Phonemes and Morphemes: The Basic Ingredients of Language o Phonemes are the most basic units of speech sounds. ▪ For example, the phoneme /t/ found in pot, and stop. o Morphemes are the smallest meaningful units of language. ▪ Some morphemes are simple words, whereas others may be suffixes or prefixes. ▪ For example, the word pig is a morpheme – it cannot be broken down into smaller units of meaning. ▪ You can combine morphemes, however, if you follow the rules of the language. For example, to pluralize pig, you can add the morpheme /-s/, which will give you pigs. o Semantics is the study of how people come to understand meaning from words. ▪ Humans have a knack for this kind of interpretation, and each of us has an extensive mental dictionary to prove it. Not only do normal speakers know tens of thousands of words, but they can often understand new words they have never heard before based on their understanding of morphemes.  Syntax: The Language Recipe o Syntax is the rules for combining words and morphemes into meaningful phrases and sentences. o Children master the syntax of their native language before they leave elementary school. They can string together morphemes and words when they speak, and they can easily distinguish between well- formed and ill-formed sentences. o Despite mastering those rules, most speakers cannot tell you what the rules are; syntax just seems to come naturally. o Syntax helps explain why the order of words in a sentence has such a strong effect on what the sentence means. ▪ For example, the following sentences have the same words, but their rearrangement results in different meanings:  A unicorn is in the garden.  Is a unicorn in the garden?  Pragmatics is the study of nonlinguistic elements of language use. o Pragmatics is guided by the cooperative principle, which states that pragmatic rules apply to conversation so entering into a conversation is essentially agreeing to cooperate. o Pragmatics reminds us that sometimes what is said is not as important as how it is said. o Flouting is the blatant disobeying of a rule of language in a way that is obvious. ▪ For example, if a student says, “I ate a 50 pound cheeseburger,” you would know he is stretching the truth, but you wouldn’t call him a liar. Pragmatics would help you understand that he implied the cheeseburger was really big.  Language in the Brain o Aphasias are language disorders caused by damage to the brain structures that support using and understanding language. o Wernicke’s area is the area of the brain most associated with finding the meaning of words. ▪ Damage to this area results in Wernicke’s aphasia, a language disorder in which a person has difficulty understanding the words he or she hears. ▪ The problem is known to be associated with semantics rather than syntax, because an 75 o Other studies involving chimpanzees taught them to communicate using sign language or artificial languages instead. This proved to be more effective than using human language as a frame of reference. 76 o Take into consideration, an alternate universe where dolphins attempt to teach humans their own system of communication. It is likely they would end up publishing skeptical critiques about the miniscule skills their human subjects acquired. o Humans have evolved a remarkably complex capacity to use language for communication, and non- humans have their own systems serving unique and adaptive functions.