Schizophrenia and Brain Disorders: Causes, Symptoms, and Treatments, Exams of Psychology

Download Schizophrenia and Brain Disorders: Causes, Symptoms, and Treatments and more Exams Psychology in PDF only on Docsity! 1 Schizophrenia A serious mental disorder characterized by disordered thoughts, delusions, hallucinations and often bizarre behaviors Positive symptoms • Symptoms that are not normally present – Hallucinations – Thought disorders – Delusions • Persecution • Grandeur • Control Negative Symptoms • Absence of behaviors that are normally present – Flattened emotional response – Poverty of speech – Lack of initiative and persistance – Anhedonia (inability ot experience pleasure) – Social withdrawal Onset of Schizophrenia • Process Schizophrenia • Reactive Schizophrenia • Onset in early 20’s, almost never after early 30’s Heredity and Schizophrenia • Concordance rate for schizophrenia in monozygotic twins reared apart is 80% • Concordance rate for monozygotic is 4 times higher than dizygotic • Incidence in children of schizophrenic parent is just under 50% (should be 75% if dominant gene, should be 1% if not genetic Seasonality effect • Increased incidence of schizophrenia in people born during late winter and early spring • Flu season when mother was pregnant • Some mothers report having had severe flu during pregnancy 2 Brain Damage • MRI scans reveal ventricles of Schizophrenics twice as large as non- schizophrenics • Negative symptoms not specific to schizophrenia; they are seen in many neurological disorders that involve brain damage, especially to the frontal lobes Discovery of Chlorpromazine • Searching for new antihistamine • This one caused to much drowsiness • Tried it as presurgical sedative on a schizophrenic woman and noted improvement in thought disorder (probably total coincidence) • Conducted test on group of Schizophrenics and it worked Investigation of Chlorpromazine • Attempt to find out what chlorpromazine does • It blocks dopamine receptors • Led to dopamine hypothesis of schizophrenia Dopamine hypothesis of schizophrenia • Schizophrenia due to abnormally increased dopamine activity in the brain Evidence for the Dopamine Hypothesis of Schizophrenia • Antipsychotic (neuroleptic) drugs such as chlorpromazine (Thorazine) or haloperidol (Haldol) control symptoms in many patients • neuroleptics block dopamine receptors • magnitude of therapeutic effect of different neuroleptics is proportional to the magnitude of dopamine blocking effect Evidence For • Neuroleptics as Anti-schizophrenic not just anti- anxiety or sedative – If sedatives then barbiturates should work but they don't – If anti-anxiety then neuroleptics should work with anxiety disorders but virtually ineffective – Neuroleptics calm hyperactive patients and make withdrawn patients more active – Anti-anxiety drugs are not effective with schizophrenia