I. DSM-IVa. Definition of mental disorderII. AutismI. SchizophreniaSchizophrenia: General FeaturesSplit mind: separation of normal perception, thought, and feelings. Not multiple personality. Distortions of thought, perception, emotion. Delusions (paranoid, grandiose). Hallucinations, auditory mainly. Social withdrawal, unresponsiveness (flat accent).Positive symptoms: thought disorder, delusions, language disturbancesNegative symptoms: flat accent, social withdrawal.DSM IV categorizes Schizophrenia into subtypes and related disordersNOS = not otherwise specifiedDemographics: about 1% of US adults are affected. Similar numbers in other countries and cultures. Onset occurs from 14-30- dementia praecox (early onset dementia), but there are childhood precursors.Sex differences: 1% in females, 1.5% in males. Occurs earlier in males with more severe symptoms and less responsiveness to drug treatmentsSES (socioeconomic state): don’t take care of themselves. Negative correlation with SES. Tend to “drift downward” personally, economically.Drug & alcohol abuse: very common among schizophrenics (50%: alcohol, marijuana, cocaine), ~ 50% smoke cigarettes.Suicide: greatly elevated risk (10%)Genetics:“Schizophrenia appears to result from one or more inherited, biological predispositions that are activated by environmental stress.”Evidence: schizophrenia and genetic relatedness; concordance rate differences among MZ, DZ twins; adoption studies; early brain abnormalitiesSome possibilities: season of birth (?); viral infection during pregnancy; strong environmental stressors (e.g. earthquakes, famine); enduring family conflictIn China, when there was a famine, the number of schizophrenics spiked“Birth in winter or spring months, when respiratory infections are frequent, is a well-established (?) risk factor for schizophrenia… elevated risks may only be in genetically suspectible individuals.”Causing influenza in maternal rodents seems to produce behavioral dysfunction in offspring, esp. post-pubertal: “deficits in social interaction, working memory, anxiety, neuropathy.”Environmental/experiential influences may contribute to the severity or duration or maintaining of the conditionSlide 13: genes for schizophrenia may not be fully expressed in the carrierPossible that placental environment can influence the expression of genes that are linked to neurodevelopment and schizophrenia.Animal models of schizophrenia:Creation of schizophrenic-like symptoms in animals. Has been done with “mind-altering drugs”, and with mutant animals lacking forebrain neurotransmitters (“gene knockout”)You can create mice with repetitive behaviors, attention deficits, altered FAPs, abnormal social behaviors.An important approach to the problem because: good controls and better causal inference; repeatable; strong treatments are possible; human-nonhuman commonalitiesCurrent thinking:Schizophrenia may be like intelligence in the sense that there may be many genes involved, each of which makes a small contribution to the phenotype.Schizophrenia might arise from micro-deletions, micro-insertions in the genome, or from copy-number variants. These may be highly idiosyncratic.Brain differences:Compared to normal controls: reduced cortical volume that is accelerated in adolescence (dementia praecox) that progresses over time: frontal & temporal gray matter, hippocampus, parietal lobes, cerebellum.Note: This is also true of the adolescent brain in the general population. The extent of gray matter reduction seems greater in schizophrenics.Increased ventricle size. Hemispheric asymmetry: In healthy males, left parietal lobe is larger than right parietal lobe. In schizophrenics, no size difference. Parietal lobe functions: attention & attention switching-inhibition, visual-spatial cognition, extensive connectedness with frontal lobes.DISC1 Gene linked to Mental Illness- codes for proteins involved in pre-natal brain development and signaling pathways for learning and moodDrug Treatments: anti-psychotic medications: discovered in 1950s. Used as part of surgical anesthesia, found to have sedative effects as well.Chlorpromazine / Thorazine / Haloperidol: reduce the positive symptoms of schizophrenia. These drugs are dopamine antagonists. They work against dopamine influence by blocking dopamine receptors. Contrast with dopamine agonists (such as amphetamine). These drugs worsen symptoms of schizophrenia.Some serious side effects (nausea, constipation, tremor, weight gain... ). Produces side-effects similar to Parkinson's disease, known to involve reduced dopamine. There are many dopamine receptors in the limbic system as well.New drug treatments (atypical drugs), such as Clozapine, are an improvement because it may have fewer side effects and its effects are more specific. May work on negative symptoms as well as positive symptoms, unlike the other drugs.Schizophrenia and violence:There is a good deal of evidence showing elevated levels of violent behavior among schizophrenics.Danish study: major mental illness patients more likely to have been convicted of crimes of violence (in a sample of 324,000). True of males and females.Finnish study: “Among male murderers, schizophrenia was 6.5 times more prevalent than in the general population” (and 15 times more prevalent among females).Perhaps true only for specific forms of schizophrenia (paranoid), and for patients who are not complying with their medication regimen. A job for the behavior engineer.PSYC 100 1st Edition Lecture 20 Outline of Last Lecture I. DSM-IVa. Definition of mental disorderII. Autism Outline of Current Lecture I. Schizophrenia Current Lecture Schizophrenia: General FeaturesSplit mind: separation of normal perception, thought, and feelings. Not multiple personality.Distortions of thought, perception, emotion. Delusions (paranoid, grandiose). Hallucinations, auditory mainly. Social withdrawal, unresponsiveness (flat accent). Positive symptoms: thought disorder, delusions, language disturbancesNegative symptoms: flat accent, social withdrawal.DSM IV categorizes Schizophrenia into subtypes and related disorders NOS = not otherwise specifiedDemographics: about 1% of US adults are affected. Similar numbers in other countries and cultures. Onset occurs from 14-30- dementia praecox (early onset dementia), but there are childhood precursors. - Sex differences: 1% in females, 1.5% in males. Occurs earlier in males with more severe