BIOLOGICAL PSYCHOLOGY: REVIEWER, STUDY NOTES, LECTURE NOTES, Study Guides, Projects, Research of Biological Psychology

Download BIOLOGICAL PSYCHOLOGY: REVIEWER, STUDY NOTES, LECTURE NOTES and more Study Guides, Projects, Research Biological Psychology in PDF only on Docsity! BIOLOGICAL PSYCHOLOGY Introduction BioPsych - The study of physiological, evolutionary, and developmental mechanisms of behavior and experience. Biological Explanations of Behavior: 1. Physiological Explanation- relates a behavior to the activity of the brain and other organs. 2. Ontogenic Explanation-Describes how a structure or behavior develops. 3. Evolutionary Explanation- reconstructs the evolutionary history of a structure and behavior. 4. Functional Explanation-Describes why a structure evolved as it did. 4 ReasonsWhy to Use Animals in Research/Experiments: 1. Similarity of behavior mechanisms and convenience to study non-humanspecies. 2. Interest in animals for their own sake. 3. Learning about animals sheds light on human evolution. 4. Legal and ethical restrictions prevent using humans for aversive research experiments. Legal Standards in Using Animals for Research: Reduction Replacement, Refinement (Self-explanatory) Nerve Cells and Nerve Impulses Neurons - Receive information and transmit it to other cells. Glia - Came from the Greek wordmeaning “glue”. Performsmany functions.  Themost distinctive feature of a neuron is its shape. Motor Neuron - • Receives excitation through its dendrites and conducts impulses along its axon to a muscle. Sensory Neuron - • Highly sensitive to a particular type of stimulation, such as light, sound, or touch. Dendrites • Comes from the Greek root word meaning, “tree”. • The dendrites is lined with special synaptic receptors, at which the dendrite receives information from other neurons. Presynaptic Terminal • Also known as the “end bulb” • The end of each branch of an axon that appears like swelling. • At that point, the axon releases chemicals that cross through the junction between that neuron and another cell. Other terms associatedwith Neurons: • Afferent Axon – brings information to the structure Glia • Efferent Axon – carries information away from a structure • Intrinsic Neuron – if cell’s dendrites and axon are entirely contained within a single structure • Also known as neuroglia. • Early investigators believed that glia were like glue that held the neurons together. that keep out most viruses, bacteria, and other harmful chemicals. How does it work? • It depends on the endothelial cells that form the walls of the capillaries. • The blood-brain barrier keeps out useful chemicals as well as harmful ones. For these chemicals to cross the blood-brain barrier, the brain needs special mechanisms not found in the rest of thebody. Genetics and Evolution of Behavior Genes are units of heredity that maintain their structural identity from one generation to another. They can be dominant, recessive, or intermediate. Chromosomes are strands of genes. DNA (deoxyribonucleic acid) • contains the genetic instructionsof organisms. • Double-Stranded • adenine, guanine, cytosine, thymine RNA (ribonucleic acid) • serves as the link between DNA and the synthesis of protein products during translation • Single-stranded • adenine, guanine, cytosine, uracil Sex-Linked and Sex-Limited Genes • The genes on the sex chromosomes (designated X and Y in mammals).A sex-linked genes. • Sex-limited gene is on an autosomal chromosome but is activated in one sex more than the other (e.g., genes that control the amount of chest hair in men or breast size in women) Mutation A heritable change in a DNA molecule. Epigenetics • deals with changes in gene expression. • An epigenetic change is an increase or decrease in the activity of a gene or group of genes. • Various experiences can turn a gene on or off. How could an experiencemodify gene expression? • Proteins called histones bind DNA into a shape that is more like string wound around a ball. • Removal of acetyl turnsoff a gene, Adding Methyl: Turns off a gene, Removing Methyl: Turns on a gene. Heredity and Environment • Even a trait with high heritability can be modified by environmental interventions. • Phenylketonuria (PKU) is a hereditary condition, but environmental interventions can modify it. Evolution is a change over generations in the frequencies of various genes in a population. CommonMisunderstanding about Evolution • Does the use or disuse of some structure or behavior cause an evolutionary increase or decrease in that feature? • Have humans stopped evolving? • Does “evolution”mean “improvement”? • Does evolution benefit the genes, not the species? It is always the genes that benefits. Evolutionary psychology concerns how behaviors evolved. The emphasis is on evolutionary and functional explanations. Altruistic behavior is an action that benefits someone other than the actor • It certainly occurs in humans. • Among nonhumans, altruism is less common. Development of the Brain Homeobox Genes - a series of genes found in vertebrates, insects, plants, and even fungi and yeast— regulate the expression of other genes and control the start of anatomical development. If amutation occurs here, itwill cause abnormality in the organism. Maturation of the Vertebrate Brain:  The human central nervous system begins to form when the embryo is about 2 weeks old.  After the early development of the brain, it will then form the forebrain, midbrain, and hindbrain.  At birth, the average human brain weighs about 350 grams. By the end of the first year, it weighs 1,000g, close to the adult weight of 1,200 to 1,400g. Growth and Development of Neurons:  Proliferation is the production of new cells.  Early in development, the primitive cells, not yet identifiable as neurons or glia, begin to migrate.  Chemicals known as immunoglobulins and chemokines guide neuron migration.  Synaptogenesis, the formation of synapses, begins long before birth, but it continues throughout life.  A later and slower stage of neuronal development is myelination, the process by which glia produce the insulating fatty sheaths that accelerate transmission inmany vertebrate axons. How does an axon find its target? • A growing axon follows a path of cell surfacemolecules, attracted by certain chemicals and repelled by others, in a process that steers the axon in the correct direction. • Eventually, axons sort themselves over the surface of their target area by following a gradient of chemicals. Nerve growth factor (NGF) • promotes the survival and growth of the axon. An axon that does not receive NGF degenerates, and its cell body dies. Apoptosis • is a programmed mechanism of cell death. A process where a neuron kills itself if its axon does not make contact with an appropriate postsynaptic cell by a certain age. Gastrulation • is one of the early stages of embryological development • Blustula (hollow ball of cells) • , ectoderm, ectoderm, endoderm Plasticity After Brain Damage Brain Damage and Short-TermRecovery Ischemia • most common type of stroke resulting from a blood clot or occlusion in an artery. Hemorrhage • less common type of stroke that results from a ruptured artery. Immediate Treatments (1) Tissue plasminogen activator (tPA),a • drug that breaks up blood clots in ischemia. • To get a benefit, it must be given within 4.5 hours after a stroke. (2) Decrease stimulation by blocking glutamate. (3) Exposure to cannabinoids is believed to (a) decrease the release of glutamate, (b) exert anti-inflammatory effects; (c ) alter brain chemistry. Vision and other Sensory Systems (Study the lecture and illustration that I discussed about vision): The visual cortex, is the primary cortical region of the brain that receives, integrates, and processes visual information that is relayed from the retinas. It is located in the occipital lobe of the primary cerebral cortex which is in the most posterior region of the brain. Motion Blindness (also called Akinetopsia) is a medical condition (although not a medical condition that is not currently recognized by the World Health Organization) in which a person cannot see objects that are moving, even though they can see the objects that do not move. Visual Agnosia- “visual lack of knowledge”is an inability to recognize objects despite otherwise satisfactory vision. It is a common result of damage in the temporal cortex. Someonemight be able to point to visual objects and slowly describe them but fail to recognize what they are. FusiformGyrus PART OF THE INFERIOR TEMPORAL CORTEX THAT RESPONDS STRONGLY ON RECOGNITION OF FACES Audition (Study the lecture and illustration that I discussed about vision): Outer Ear • Pinna - Familiar Structure of flesh and cartilage attached to each side of the head. • Ear Canal - vibration funnel them into the middle ear. Middle Ear • Tympanic membrane,also known as eardrums, • Eustachian Tube – helps the eardrum to work well by keeping the air pressure balanced on both sides. Inner Ear • Cochlea is the snail-shaped structure of the inner ear, • Hair cells,also known as the auditory receptors. Amusia • AKA “tone deafness” • 4% of people have this, in estimation • They do not detect a change less than about the difference between C and C- sharp • Trouble recognizing tunes • and gauging people’s mood Vestibular System – part of the inner ear; the sensory system that provides the leading contribution to the sense of balance and spatial orientation • Impairment of vestibular sensation can lead to frequent loss of balance. • The vestibular organ consists of the saccule, utricle, and three semicircular canals. • Pacinian corpuscles - Receptors that respond best to sudden displacement of the skin or high-frequency vibrations. Fast Twitch Muscle Fibers • Prolonged use of fast-twitch fibers results in fatigue because the process is anaerobic, using reactions that do not require oxygen at the time but need oxygen for recovery. • Using them builds up an oxygen debt. • They fatigue faster but are used in powerful bursts of movements like sprinting. • They support quick and powerful movements. Muscle Control by Proprioceptors • A proprioceptor (from the Latin proprius, meaning “one’s own”) is a receptor that detects the position or movement of a part of the body—in these cases, a muscle. • Muscle proprioceptors detect the stretch and tension of a muscle and send messages that enable the spinal cord to adjust its signals. When a muscle is stretched, the spinal cord sends a signal to contract it reflexively. • This stretch reflex is caused by a stretch; it does not produce one. • Themuscle spindle sends a message to a motor neuron in the spinal cord, which in turn sends a message back to the muscle, causing a contraction (Dimitriou, 2014). Units of Movement Voluntary and InvoluntaryMovements • Reflexes are consistent automatic responses to stimuli. We generally think of reflexes as involuntary because they are insensitive to reinforcements, punishments, and motivations. The stretch reflex is one example. Another is the constriction of the pupil in response to bright light. • Few behaviors are purely voluntary or involuntary, reflexive or non-reflexive. Walking, which we think of as voluntary, includes involuntary components. When you walk, you automatically compensate for the bumps and irregularities in the road. The knee-jerk reflex that your physician tests contributes to walking; raising the upper leg reflexively moves the lower leg forward in readiness for the next step. • You also swing your arms automatically as an involuntary consequence of walking. • A ballistic movement, such as a reflex, is executed as a whole: Once initiated, it cannot be altered. However, most behaviors are subject to feedback correction. Mirror Neurons • Active both during preparation for a movement and while watching someone else perform the same or a similar movement • First reported in the premotor cortex of monkeys • and may be important for understanding other people, identifying with them, and imitating them. • Mirror neurons in part of the frontal cortex become active when people smile or see someone else smile. • Many mirror neurons modify their properties by learning, and probably developed their original properties by learning as well. • Autism or schizophrenia - lack of mirror neurons Basal Ganglia • applies collectively to a group of large subcortical structures in the forebrain • Significant for spontaneous and self – initiated behaviors. • Regulates vigor of movement Movement Disorders: Parkinson’s Disease • strikes 1 to 2 percent of people over age 65 • Results from the gradual loss of dopamine-releasing axons from the substantia nigra to the striatum(part of the basal ganglia) • Researcher have identified at least 28 gene variants that increases the risk of Parkinson’s disease, but none of those genes by itself has a major effect. • An accidental discovery implicated exposure to toxins as another factor in Parkinson’s disease • MPTP, a chemical that the body converts toMPP+, which accumulates in, and then destroys, neurons that releases dopamine, partly by impairing the transport ofmitochondria from the cell body to the synapse • HYPOTHESIS: people are sometimes exposed to hazardous environmental chemicals that can damage the cells of the substantia nigra Huntington’s Disease • Severe neurological disorder • The prevalence varies geographically and ethnically • Affects about 17 per 100,000 Americans of European ancestry • Can occur at any age, but most often between the ages of 30 and 50 • Motor symptoms usually begin with arm jerks and facial twitches • Associatedwith gradual, extensive brain damage, especially in the basal ganglia but also in the cerebral cortex • Also suffer psychological disorders • The gene for Huntington’s disease is on chromosome number 4 • The more C-A-G repetitions someone has, the earlier the probable onset of the disease • One gene – an autosomal dominant gene – is responsible • People with the greatest number of repeats have the earliest onset disorders than for those with later onset • Identification of the gene for Huntington’s disease led to the discovery of the protein that it codes, which has been designated huntingtin. • Huntingtin occurs throughout the human body, although itsmutant form produces no known harm outside the brain. Wakefulness and Sleep Endogenous Patterns • Endogenous circannual rhythm - rhythm that lasts for approximately one year. • Endogenous circadian rhythms - animals produces rhythm that lasts about a day. Posterior areas of Cerebral Cortex • Responsible for theactivity of the circadian rhythm Mechanisms for Biological Clock Suprachiasmatic Nucleus • main driver of rhythms for sleep and body temperature • it generates circadian rhythms itself, rhythm follows the pace of the donors, not the recipients • damage to the SCN causes the body rhythms to be erratic. Setting and resetting the Biological Clock Zeitgeber • The stimulus that resets the circadian rhythm. • German term that means “time-giver” • External or environmental cues Examples: • Light – most dominant zeitgeber. • Temperature • Tides – for marine animals. Jet lag • Discruption of circadianrhythms due to crossing time zones • Mismatch between the internal circadian clock and external time contradictory) used to refer to species that lack eye movement. • rapid movements in the eyes occur during sleep. • activity decreased in the primary visual cortex, the motor, and the dorsolateral prefrontal cortex, but increases in parts of the parietal and temporal cortex. Shift work • People who sleep irregularly due to their profession, find that their duration of sleep depends on when they go to sleep. Morning people • “larks” • Awaken early and reach their peak of productivity early. Evening people • “owls” • Warm up more slowly and reach their peak in the late afternoon or evening. Stages of sleep. Stage 1 is dominated by irregular, jagged, low voltage waves. Brain activity is less than relaxed wakefulness, but higher than in other sleep stages. Stage 2 – kcomplex and sleep spindle is starting to show. Stage 3 is slowwave sleep, is evident in this stage, together with fewer slow waves. Stage 4 has a lot more of the slow wave sleep. Slow-wave sleep indicates that neuronal activity is highly synchronized. Heart rate, breathing rate, and brain activity decreases. slow, large- amplitude waves become common. Paradoxical/Rem Sleep • deep sleep in some ways and light in others. (paradoxical = apparently self- BrainMechanisms OfWakefulness, arousal, And Sleep: • The hypothalamus, has intermingled neurons, that promote wakefulness and some that promote sleep. • One axon pathway from the hypothalamus releases the excitatory neurotransmitter histamine, which enhances arousal and alertness throughout the brain. • Many antihistamine drugs, often used for allergies, counteract this transmitter and produce drowsiness. Antihistamines that do not cross the blood-brain barrier avoid that side effect. • Another pathway from the hypothalamus,mainly from the lateral and posterior nuclei of the hypothalamus, releases a peptide neurotransmitter called either orexin or hypocretin. • The axons releasing orexin extend from the hypothalamus to the basal forebrain and many other areas, enhancing wakefulness and activity. • Orexin is not necessary for waking up, but it is necessary for staying awake. That is, most adult humans stay awake for roughly 16 to 17 hours at a time, even when nothing much is happening. Reproductive Behaviors in Early Stages of Development Both female andmalemammals • start with the same anatomy • set of Mullerian ducts (precursors to female internal structures) andWolffian ducts (for males) • undifferentiated gonads Males: • SRY GENE (found on the Y chromosome) causes the undifferentiated gonads to develop into testes (sperm-producing organ) • Androgens cause the Wolffian ducts to develop into seminal vesicles (sac-like structures that store semen) and vas deferens (a duct from the testis into the penis). • The testes produceMüllerian inhibiting hormone (MIH), which causes the Müllerian ducts to degenerate • Final in the development of a penis and scrotum. Females: • no SRY gene, • gonads develop into ovaries > testes. • Their Wolffian ducts degenerate. • Because their ovaries do not produce MIH, females’ Müllerian ducts develop and mature into oviducts, uterus, and the upper vagina. Males’ testes producemore androgens than estrogens (hormones that are more abundant in females). Females’ ovariesproducemore estrogens than androgens. Adrenal glands produce both androgens (male) and estrogens (female). These two types of hormones have similar effects in someways and opposing effects in others. Testosterone:most widely known androgen, while most prominent type of estrogen. Progesterone is another predominantly female hormone that prepares the uterus for the implantation of a fertilized ovum and promotes the maintenance of pregnancy. X and Y CHROMOSOME - At least three genes on the Y chromosome (found only in men) are active in specific brain areas. • One gene on the X chromosome is active only in the female brain. (Study about the discussion I did about Transport of sperm.) Organizing Effects of Sex Hormones • Sex hormones determine whether the body develops female or male genitals, and they alter certain aspects of brain development. Sex hormones produce additional organizing effects at puberty: • Breast development (female) Facial hair and penis growth (male) • Changes in voice • Male-female differences exist in the anatomy of certain parts of the hypothalamus. Sex Differences In The Brain Male and female brain differ in many ways. • Average in various areas, pituitary gland, parts of the hypothalamus, and elsewhere. • The female hypothalamus generates a cyclic pattern of hormone release, while hypothalamus releases hormones more steadily. Sex Difference In Play Children who show the greatest preference for boy-typical activities at age 3 usually show the greatest amount of boy-typical activities at age 13, and vice versa. Studies: • Girls exposed to high testosterone during prenatal = slight elevated interest in boys’ toys. • On the other hand, boys exposed to high phthalate level (which inhibit testosterone production) = interest in girls’ toys than boys’ toys Activating Effects Of Sex Hormones • At any time in life, not just during sensitive periods, current levels of testosterone or estradiol exert activating effects, temporarily modify behavior. Behaviors can also influence hormonal secretions. • Sex hormones bind to receptors that increase responses in parts of the hypothalamus, including the ventromedial nucleus, the medial preoptic area (MPOA), and the anterior hypothalamus. • Testosterone is essential for male sexual arousal and acts partly by increasing touch sensitivity in the penis. It primes the MPOA and several other areas of the brain to release dopamine. MPOA neurons release dopamine strongly during sexual arousal. The more dopamine they release, the more likely they are to copulate (have sexual intercourse). • Dopamine stimulates sexual activity, while the neurotransmitter serotonin inhibits it by blocking its release (Hull et al., 1999). Many antidepressant drugs increase serotonin activity, and one of its side effects is decreased sexual arousal. • It has been found that levels of testosterone positively correlate with men’s sexual arousal and their drive to seek sexual partners. Researchers have found that, on average, married men and men living with a woman in a committed relationship have lower testosterone levels than single, unpairedmen of the same age (M. McIntyre et al., 2006). • Marriage decreases testosterone levels because of decreased need to compete for a sexual partner. To support this, a study found increased testosterone levels around the time of a divorce (Mazur & Michalek, 1998). • Another interpretation is that men with lower testosterone levels are more likely than others to marry and remain faithfully married (van Anders & Watson, 2006). • Also, both men and women with high testosterone levels are more likely than average to seek additional sexual partners, even after they marry or establish a long-term relationship (M. McIntyre et al., 2006; van Anders, Hamilton, & Watson, 2007). • Decreases in testosterone levels generally decreasemale sexual activity. Effects of Sex Hormones onNon-Sexual Characteristics: • One well-documented gender difference in behavior is that women tend to be better than men at recognizing facial expressions of emotions. • Sex hormones also influence behaviors not directly related to sexual reproduction, such as the ability to recognize emotional expressions. Variations in Sexual Behavior and Sexual Selection:Genes that make an individual more appealing to the opposite sex will increase the probability of reproduction Interest in Multiple Mates • More men than women seek opportunities for casual sexual relationshipswithmany partners. • From anevolutionary standpoint of spreading one’s genes, men can succeed by either of two strategies • Be loyal to one woman and devote your energies to helping her and her babies. • If the woman’s husband is infertile, thenmating with another man could be her only way of reproducing. • A woman has thepossibility of “trading up” and abandoning her first mate for a better one. • Researchers have no direct evidence that genes influence people’s preferences for one mate or many. What Men andWomen Seek in a Mate? • Almost all people prefer a romantic partner who is healthy, intelligent, honest, and physically attractive. • Women prefer a mate who is likely to be a good provider. • Men tend to have a stronger preference for a young partner. • In countries where women have good educational, economic, and employment opportunities, a woman is more likely to choose a partner close to her own age and less likely to choose based on wealth Differences in Jealousy • Traditionally, men aremore likely to be more jealous than women. • Men have beenmore jealous of a wife’s possible infidelity than women have been jealous of a husband’s infidelity. • Aman has to be sure that the children he supports are his own • An unfaithful wife threatens a husband’s uncertainty. • Men aremore jealous about sexual infidelity. • Women aremore jealous in emotional infidelity. • Both men and women are upset about either sexual or emotional infidelity Gender Identity and Gender Differentiated Behaviors • Gender identity is what we consider ourselves to be. • Sex differencesarebiological differences between males and females. • Gender differences result from people regarding themselves as male or female. • Most people accept the gender identity that matches their external appearance Intersexes • A personwhose sexual development is intermediate, alternative is to use the term differences of sexual development. • Hermaphrodite - from Hermes and Aphrodite in Greek mythology - Anatomy intermediate betweenmale and female or shows a mixture of both anatomies. • True Hermaphrodite - has both testicular and ovarian tissue. • While true hermaphrodites are rare, some are fertile as either male or female, although no cases are known in which someone was fertile as both. • Some people develop an intermediate appearance because of an atypical hormone pattern, Congenital Adrenal Hyperplasia (CAH) • Meaning overdevelopment of the adrenal glands from birth.