Listen to the audio lecture while viewing these slides1Psychology 372Physiological PsychologySteven E. Meier, Ph.D.Schizophrenia2Psyc 372 – Physiological PsychologyOverview• Probably consists of more than one disorder• Is the most devastating disorder• Occurs in about 1% of the population• Another 2-3% have Schizo typal Personality Disorder• No major sex differences in prevalence rates• Costs of care >30 Billion Dollars annually• Many homeless are untreated or stop meds.• Generally,• Is a disorder of thought and emotion• Is not a “split-personality” dis order.3Psyc 372 – Physiological PsychologyCharacterized by• Disorganized Thoughts• Hallucinations• Delusions• Bizarre behaviors4Psyc 372 – Physiological PsychologyTwo Different Types of Schizophrenic Symptoms• Positive •Negative• Often are preceded by Prodromal signs• Social Isolation• Odd Behavior and Ideas• Poor Hygiene• Blunted Affect5Psyc 372 – Physiological PsychologyPositive Symptoms• Usually occur during psychotic episodes• Usually involve distinct abnormal behaviors•Includes •Delusions•Hallucinations• Disorders of thought 6Psyc 372 – Physiological PsychologyDelusions• Are beliefs that are contrary to reality• Can involve • Control •Grandeur•Persecution7Psyc 372 – Physiological PsychologyHallucinations• Are perceptions that occur in the absence of stimuli •Can be •Visual• Auditory (Most Common)•Olfactory•Tactile8Psyc 372 – Physiological PsychologyDisorders of Thought•Can be •Disorganized • Irrational9Psyc 372 – Physiological PsychologyNegative Symptoms• Usually occurs during non-psychotic periods.• Generally involves a loss of normal behaviors• Reduced speech • Low initiative• Social withdrawal• Diminished affect10Psyc 372 – Physiological PsychologyDiagnosis• Must be continuously ill for at least 6 months.• Need to have one psychotic phase where you have •Delusions•Hallucinations• Disordered thoughts, incoherence, or other symptoms.• See DSM IV for more detail11Psyc 372 – Physiological PsychologyMany Subtypes of Schizophrenia• Based on the symptoms that are presented.• Paranoid• Catatonic•Disorganized•Others12Psyc 372 – Physiological PsychologyCauses of Schizophrenia13Psyc 372 – Physiological PsychologyMany Different Hypotheses• Genetics• Brain Abnormality Hypothesis• Dopamine Hypothesis14Psyc 372 – Physiological PsychologyGenetic Contributions• Highly probable schizophrenia is genetic• Is probably not caused by one gene• Would show in all monozygotic twin studies.• Is probably caused by the combination of several genes.• Not totally sure which ones• Has been identified with genes on Chromosome 22 and Chromosome 6.15Psyc 372 – Physiological PsychologyBrain Abnormality Hypothesis• Identified by CT and Cerebral Blood Flow Studies• Some Patients have one or more of the fo llo w ing.• Reduction of blood flow to the left Globus Pallidus• Problems in t he frontal lobes• Medial temporal lobe is thinner• Anterior Hypothalamus is s maller (especially left side)• Lateral and third ventricles are enlarged• Sulci are also enlarged (especially in the temporal and frontal lobes•Indicated reduced numbers of neurons.16Psyc 372 – Physiological PsychologyCauses of Brain Damage• Birth trauma (obstetrical issues)• Viral infections that impair neural development during the second and third trimester.•Nutritional issues •Others17Psyc 372 – Physiological PsychologyConclusion• Not purely a genetic problem• Not purely a abnormality problem• Is probably a combination problem triggered by an environmental event• E.g., Infants exposed to influenza during second and third trimesters.• Not really sure what causes the disorder18Psyc 372 – Physiological PsychologyDopamine Hypothesis •Contends: • Positive symptoms occur due to increased levels of Dopamine.• Get increased stimulation of Dopaminergic synapses19Psyc 372 – Physiological PsychologyHistory•Larobit• Was looking for a drug to calm patients before neurosurgery. • Found Chlorpromazine worked very well.• Hypothesized it might be used on other patients• Delay and Deniker found that high dosages of Chlorpromazine calmed patients with schizophrenia or manic-depressive symptoms20Psyc 372 – Physiological PsychologyChloropromazine and other Phenothiazines• Part of the drug group – Typical Antipsychotics• Other Typical Antipsychotics • Butyrophenones (Haloperidol)• Thioxanthenes (chlorprothixene)• Have clear effects on schizophrenia•Block •Delusions•Hallucinations• Disordered thinking21Psyc 372 – Physiological PsychologyAtypical Antipsychotics• Are another group of drugs• Are better for negative symptoms and cognitive problems• Also have fewer side effects•Includes•Clozapine•Risperidone•Olanzapine22Psyc 372 – Physiological PsychologyAtypical Antipsychotics• Bind to D3 and D4 receptors• Are in the limbic system and cortex• Few in the BG• Reason for few extrapyramidal side effects23Psyc 372 – Physiological PsychologySupport for Hypothesis• Drugs that increase dopamine levels (Amphetamine, Cocaine) can produce positive symptoms of schizophrenia• Drugs that block DA receptors also reverse schizophrenia24Psyc 372 – Physiological PsychologyWhich Receptors?• At least five types of Dopamine receptors•D1 –D5• D1 and D5 (D1a) Increase CAMP• Are in the cortex, hippocampus, caudate nucleus• D2 Group (D2, D3, D4) decrease CAMP• Are in the caudate, putamen, nucleus accumbens, amygdala, hippocampus, parts of the cortex.• Are also in the caudate and putamen.25Psyc 372 – Physiological PsychologyFour Major Systems for Dopamine• Tuberoinfundibular• Nigrostriatal• Mesolimbic•Mesocortical26Psyc 372 – Physiological PsychologyNigrostriatal• Contributes to Parkinson’s Disorder• May be involved with short-term and long- term antipsychotic side effects.•Short-Term •Hand tremor•Muscle rigidity•Long Term•Tardive Dyskinesia 27Psyc 372 – Physiological PsychologyMesolimbic• Several structures• Is involved with emotion and memory.• Symptoms of thought and perception disturbances are characteristic of schizophrenia and psychomotor epilepsy• Carlsson• Hypothesizes the positive symptoms result from overactivity of this system28Psyc 372 – Physiological PsychologyMesocortical• Originates in ventral