Ch13 schizophrenia - Lecture notes 13 PDF

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Abnormal Psychology Chapter 13: Schizophrenic Disorders 

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Overview o Symptoms of schizophrenia involve deterioration of basic functions affecting individuals’ thoughts and perceptions o Symptoms must occur in the absence of other disorders (mood, delirium, dementia, substance abuse) – among mental disorders, is leading cause of disease burden, and financial costs for US around $63B o Phases of schizophrenia  Prodromal phase – obvious deterioration in functioning, change in personality with characteristics similar to schizotypal personality disorder, including peculiar behaviors and perceptual experiences  Would just be schizotypal without the active phase  Men – more schizotypal traits during prodromal  Active phase = to psychotic break– symptoms such as hallucinations, delusions, disorganized speech are present  Residual phase – signs and symptoms similar to that of the prodromal phase – positive symptoms may improve, but negative symptoms and impairment often continue o The most common symptoms of schizophrenia include changes in the way a person thinks, feels, and relates to other people and the outside environment Symptoms o There is no specific set of symptoms characteristic of all schizophrenic patients, but classes of symptoms include the following:  Positive (psychotic) symptoms – presence of abnormal functioning (ex: hallucinations, delusions  Negative symptoms – absence of normal functioning (ex: social withdrawal, lack of initiative, and deficits in emotional responding)  Disorganization – verbal communication problems and bizarre behavior o Positive symptoms – characterized by the presence of an aberrant response  Hallucinations – sensory experiences not caused by actual external stimuli – perception w/o sensation, psychotic symptoms  Usually auditory (hearing voices)  Often include voices commenting on patient’s behavior or giving instructions – often unwelcome friends  Do not imply that these symptoms are beneficial/adaptive, but suggests they are characterized by the presence of an aberrant response  Voices are real to them and patients do not notice until someone tells them there is no one there  Delusional beliefs – idiosyncratic beliefs that are rigidly held despite their illogical and unreasonable nature  Defended even when shown contradictory evidence – false beliefs are based on incorrect inferences about reality

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Person is preoccupied with these irrational beliefs and unable to understand another person’s perspective with regard to the belief  Common delusions: thoughts being inserted into the person’s head, the belief that others can read his/her thoughts, and grandiose or paranoid delusions o "Special powers” = are truth but fragmented o CIA stuck probe into my head, following me around o I have a message from God to save people  In clinical practice, delusions are often complex and difficult to define  content can be very bizarre and confusing  The subjective experiences of people with this disorder serve as a valuable resource for knowledge about delusions o Negative symptoms –the absence/reduction of responses/functions that should normally be present (usually what is left after person is treated for positive), more stable than positive symptoms  Affective and emotional disturbances  Diminished emotional expression (aka blunted affect) – failure to exhibit signs of emotion/feelings --- schizoid  Anhedonia – inability to experience pleasure, emotional deficit – schizoid  Avolition and alogia  Avolition – indecisiveness, ambivalence, loss of willpower, a lack of volition/will  Alogia – impoverished thinking / poverty of speech, along with thought blocking  patients have little to say, cannot maintain a train of thought / speechlessness o Short, no elaboration  Apathetic – socially withdrawn as a symptom and coping strategy o Disorganization *** usually with positive/active, but can be negative  Thinking disturbances – definitely prominent stream of consciousness and attentional difficulties  Disorganized speech – saying things that don’t make sense, aka thought disorder  Loose associations – derailment or abruptly shifting topics – Word Salad  Tangentiality – irrelevant/unrelated responses to conversation topic  Perseveration – saying things over and over, constantly repeating the same word/phrase  Abnormal motor behavior  Catatonic behavior – involves obvious reductions in reactivity to stimuli – immobility and muscular rigidity, or excitement and overactivity, waxy flexibility (like a mannequin or pipe cleaner)  often associated with a stuporous state or generally reduced responsiveness o “I couldn’t move” but will tell you what happened afterwards

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o Negative symptoms occurring in an active phase Inappropriate affect – incongruity between emotional state/behavior or the lack of adaptability in emotional expression – schizotypal especially (inappropriate emotional responses to situations)

o Video patients  #1 male  Suicidal ideation, racing thoughts, negative symptom: flat affect (decreased outward expression of emotional state)  40-50% patients admit suicide, 10-15% success rate  Delusion: paranoid  2# male – r/o schizoaffective, mood disorder with psychotic features  Tv tooth – in your scalp and listen to you for years  DDx: medical conditions – deliria, dementias, more commonly olfactory/tactile hallcinations, order TSH, electrolytes, HPR  Medications: steroids,  Intox: hall, coke, phencycline, meth, order u-tox, Bal  Withdrawal: alcohol, benzos  Delusion: thought broadcasting – considered a bizarre delusion – tv tooth  Female #1  Suicidal ideations -- > 6 mo continuous social/occupational delusions  Two or more:  Delusion: persecutory – “those ppl at ____ are always talking about me, calling hospitals”  Losing time, inability to recall  Negative symptom: asociality  Disorganized speech – loose associations  Hallucination: auditory – “Michael”  Diagnostic criteria – must rule out general medical conditions and substance abuse  Male 3  Inappropriate affect  Can only really treat positive delusions Diagnosis o History  Eugen Bleuler (1911) suggested the name schizophrenia to refer to “splitting of mental associations”  One unfortunate consequence of this description is confusion with dissociative identity disorder o DSM-5 contains 6 criteria for schizophrenia  2+ of the following for a significant portion of time during a 1 mo period – at least 1 must be (delusions, hallucinations, disorganized speech)  Delusions  Hallucinations

 Disorganized speech  Grossly disorganized/catatonic behavior  Negative symptoms  Functioning in a major area of life must suffer for a meaningful portion of time since the onset of the symptoms  Continuous signs of disturbance for at least a 6 mo period  Schizoaffective and depressive/bipolar must have been ruled out  Symptoms not attributable to the effects of a substance  If there is a history of autism spectrum disorders, the diagnosis of schizophrenia may only be made if prominent delusions/hallucinations + other required symptoms of schizophrenia are also present for 1+ month o Subtypes  Earlier versions of the DSM (tracing back to the DSM-1) divided schizophrenia into subtypes, which included the catatonic/disorganized/paranoid/residual/undifferentiated subtypes – DSM-5 got rid of them  Schizophrenia with ____ traits instead  o Related psychotic disorders – does not always lead to schizophrenia  Delusional disorder – individual does not meet the full symptomatic criteria for schizophrenia  exhibits preoccupation with nonbizarre delusions (spouse is cheating, thinking people are talking about you)  Presence of hallucinations, disorganized speech, or grossly disorganized/catatonic behavior rules out this diagnosis  Sounds a lot like paranoid personality disorder, but does not cause impaired social/occupational functioning  Brief psychotic disorder – individual exhibits psychotic symptoms for 1+ day but no longer than one month, often following a markedly stressful event  Schizophreniform disorder – same diagnostic criteria as schizophrenia but for a reduced duration – can lead to schizophrenia – treating symptoms more important than treating exact diagnosis – don’t know how long Rask has been having symptoms so schizophrenia  Schizoaffective disorder – an ambiguous/somewhat controversial category  symptoms of schizophrenic disturbance overlap with a depressive/manic episode, but psychotic symptoms are present at some point without mood disorder symptoms  Diagnosed by the presence of delusions and hallucinations for at least 2 weeks not during the depressive or manic phase – must be separate o Depressive/bipolar with psychotic symptoms-only during affective episodes  Shared psychotic disorder – someone with psychotic symptoms and if isolated with another person, other person might become psychotic also o Course and outcome

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Typically begins during adolescence/early adulthood and typically has a poor outcome Has historically been seen as severe/progressive, but some people with schizophrenia have more positive outcomes Psychotic severity at initial assessment  is best predictor of symptom severity at follow-up Recent evidence indicates that while some patients do have positive outcomes, relatively few are able to achieve successful aging Manfred Bleuler studied 208 schizophrenic patients who had been admitted to Swiss hospitals during 1942-43. After 23 years, 53% of patients were recovered/significantly improved

Frequency o Lifetime morbidity risk is approx. 1%, 1/100 people will experience/display symptoms of schizophrenia at some point in their lives o Gender differences in onset and course  Men 30-40% >>> women  Early onset affects men more often than it affects women, while later onset affects women more than it affects men  Males >> to experience negative symptoms  Some theorists argue there are 2 different types of schizophrenia – one earlier onset for men and another occurs later and affects women,  Some say single disorder and is expressed differently in men and women  TRIGGER IN ENVIRONMENT  Drugs taken during pregnancy/virus can cause hormonal differences and harm fetus in pregnancy/birth o Cross-cultural comparisons – testify to importance of influence in shaping experience and expression of psychotic symptoms  Although observed in virtually every culture, frequencies vary from 8 to 43 cases for every 100k people  Higher incidence occurs in urban > rural areas, but socioeconomic status does not appear to play a substantial role in frequency  Substantial cross-cultural differences have been uncovered regarding the course of schizophrenia  Clinical/social outcomes better in developed countries than in less developed countries – less social pressure to behave a certain way Causes o Biological factors – if not 100% for MZ twins, environmental factor is real  Strong support for a genetic influence  Genetics – role of genetics has been studied more extensively with schizophrenia than with any other mental disorder (suggests importance!)  Family studies – as genetic similarity increases between two people, the risk for schizophrenia increases  for example, siblings have a 50% chance, and nieces/nephews/cousins have a 25% chance

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Twin studies – higher concordance rates among schizophrenics for monozygotic (48%) > dizygotic twins (17%)  Adoption studies – children of schizo parents who are adopted by nonschizo parents = likely to be diagnosed as they would be if the schizo parent raised them o One study of children removed from S mothers before 3 days old (w/o contact w/mothers/family) still found a 16.6% lifetime morbidity risk of schizophrenia  Linkage studies o Theoretically, genetic influence could be due to a single/# of genes – polygenic influence is most likely o Research has not been able to specify gene(s) responsible, but specific regions of chromosomes have implicated o The enzyme, catechol-O-methyltransferase (COMT), involved in breaking down dopamine, may play an important role in schizophrenia, COMT gene is on chromosome 22 o Brain marker of poor memory in schizophrenia patients identified – possible key to understanding, treating cognitive symptoms of disease  Inherit specific variants in a gene related to “synaptic pruning” (low usage and deterioration between neurons) – also present in bipolar disorder  Spectrum of schizophrenic disorders – the overall pattern of results suggests that vulnerability to schizophrenia is sometimes expressed as schizophrenia-like personality traits and other types of psychoses  Molecular genetics o the mode of transmission has not been well-identified o although research suggests a genetic component, no specific genes related to schizophrenia have been identified conclusively  the COMT gene has attracted special interest as it is associated with a small but consistent increase in schizophrenia likelihood  Pregnancy and birth complications – mothers of people who develop schizophrenia were more likely to have experienced problems before and during birth/injury  possible that pre- and perinatal problems interact with genetic factors  Viral infections – people with schizophrenia are more likely to have been born during the winter months  possible they had more viral infections during winter months, but this hypothesis has not received direct support Neuropathology – identifying differences in the structure of the brain

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Structural brain imaging – magnetic resonance imaging (MRI) – found smaller total brain tissue volume, enlarged ventricles, and smaller size limbic system structures in people with schizophrenia o unclear if these differences are a sign of generalized brain deterioration o unclear if these differences are associated with specific types of schizophrenia o decreased size of hippocampus, amygdala, and thalamus  Functional brain imaging – positron emission tomography (PET) – suggests dysfunction in frontal cortex/temporal lobes of people associated with schizophrenia and mood disorders  Conclusions on neuropathology o Schizophrenia associated with diffuse patterns of neuropathology o Many patients with other psychiatric and neurological disorders show similar patterns of brain dysfunction/structure, which include some regions of the prefrontal cortex and several regions in the temporal lobes o Brain imaging techniques identify group (not individual), differences in schizophrenia and are not useful diagnostic tools  Neurochemistry  Dopamine hypothesis o Developed while trying to understand how antipsychotic drugs called neuroleptics decrease symptoms of schizophrenia o Unclear if people with S show differences in dopaminergic activity and D2 receptors PRIOR to taking antipsychotic medication o Dopamine hypothesis focuses on function of specific dopamine pathways in the limbic area of the brain  Dopamine hypothesis is overly simplistic o Some patients do not respond to drugs which block dopamine o With antipsychotics, dopamine blockage is immediate, but symptoms do not remit for days to weeks o New antipsychotic drugs act primarily on other neurotransmitters, but they are also effective o Schizophrenia may involve a complex interaction between dopamine/serotonin receptors  Current theories focus on other neurotransmitters, including serotonin, glutamate, and GABA o Social factors – environmental events play an important role  Social class – an inverse relationship exists between social class and schizophrenia

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Social causation hypothesis – social class hardships cause schizophrenia, such as stress, social isolation, poor nutrition  Social selection hypothesis** – people with schizophrenia gradually fall into the lower social classes, individuals cannot hold a job or complete higher education  Research supported both hypotheses to some extent  Higher risk has been reported among social immigrants (people who have moved to a new country) – may be partially due to the fact that migrants tend to settle in cities where they may face greater exposure to discrimination  Social adversity might increase risk for schizophrenia (different culture, adapt, culture shock)  In general, results of studies on socioeconomic status suggest schizophrenia may be at least partially influenced by social factors o Psychological factors  Family interactions – previously hypothesized communication/behavior within families was a causal factor  this is not the case, however (most of these initial studies lacked control groups)  Significant impact (as opposed to etiology)  For people with schizophrenia, relapse is associated with family patterns of interaction characterized by high levels of expressed emotion (EE) (negative/intrusive attitudes/behavior towards the patient)  Can experience negative symptoms after hospital (mistaken for not talkative, lazy, no motivation, blamed for behaviors)  Family does not understand is part of disorders  High EE also predicts relapse for other disorders  Cross-cultural studies reveal that high EE tends to be more prominent in Western countries, possibly serving to explain the more severe course/outcome of the disorder in the West  Patients with mood disorders/eating disorders/panic disorder with agoraphobia/OCD more likely to relapse following discharge if they are living with a high EE relative o Interaction between genetics and environment provides the most sensible model to explain schizophrenia The search for markers of vulnerability o The workgroup for DSM-5 considered including attenuated psychosis syndrome, which would involve the prodromal symptoms of schizophrenia, but was ultimately placed in section 3 (conditions for further research) – because no clear psychotic disorder, essentially schizotypal, but risk state for later schizophrenia is not a diagnosis o A promising option might be to identify the endophenotype {component or trait which lies somewhere on the pathway between the genotype (lays foundation for disorder) and full-blown symptoms of the disorder} o Ideally, any markers will meet the following criteria:

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Able to distinguish between those who have/have not developed schizophrenia  Stable characteristic over time  Able to identify biological relatives of people with schizophrenia  Able to predict who will develop schizophrenia  Vulnerability markers = endophenotypes o Possible markers include:  Working memory impairment  People w/S show deficits on the n-back task – subjects asked to identify with symbols they’ve seen previously  Working memory problems stable for S patients and also found within unaffected first-degree relatives of schizophrenic persons  Many people with schizophrenia also show deficits with central executive functioning or the manipulation of data that are held in storage buffers  Eye-tracking disfunction  People with schizophrenia exhibit rapid eye movements instead of smooth-pursuit tracking, specifically while tracking the motion of a pendulum/similarly oscillating stimulus  Eye-tracking deficits may identify people with a particular form of schizophrenia  Approx. 50% of first-degree relatives show similar smooth-pursuit impairments Treatment o Antipsychotic medication  Use of medications with people with S began in 1950 with phenothiazines (ex: Thorazine), which had a calming effect and allowed for deinstitutionalization  Antipsychotic drugs reduce severity of/sometimes eliminate symptoms  About ½ of patients show significant improvement within 4-6 weeks, 30-40% show mild improvement, 25% show no improvement o Positive symptoms respond better than negative symptoms o Need support system to prevent relapse and take meds  Continued maintenance medication after the acute phase may reduce relapse rate from 65-70% to about 40%  Motor side effects  Extrapyramidal symptoms (EPS) – muscular rigidity, tremors, restless agitation, involuntary postures, motor inertia are quite common  may diminish after 3-4 months o Dopamine blockage most directly associated with lack of positive symptoms o Other meds can minimize severity of EPS  Tardive dysk...