1、2022年10月10日星期一Schizophrenia精神分精神分裂症裂症Schizophrenia精神分裂症lOne of the psychotic disorderslMajor disturbances in:Thought Emotion Behavior lDisordered thinkinglFaulty perception and attentionlInappropriate or flat emotionslBizarre motor activitylDisrupted interpersonal relationshipsSchizophrenialDisorder
2、 impacts families&friends Difficult to live with someone who experiences delusions,hallucinations,and paranoia.Social skills deficits common Isolation,few social contactslSymptoms impact employability Often lead to unemployment&homelessnesslSubstance abuse&suicide rates highSchizophrenialLifetime pr
3、evalence 1%lOccurs equally in men and womenlOnset typically late adolescence or early adulthood Men diagnosed at a slightly earlier agelDiagnosed more frequently in African Americans May reflect diagnostician biaslComorbidity:substance abuseClinical Description of SchizophrenialNo single essential s
4、ymptom Heterogeneity of symptoms across patients Positive&negative symptoms positive,disorganized&negative symptomsPositive Symptoms:excesses&distortionslDelusions Firmly beliefs held contrary to reality Resistant to disconfirming evidence Persecutory delusions common:65%lHallucinations Sensory expe
5、riences in the absence of sensory stimulation from the environment More often auditory(74%)than visual Patients misattribute their own voice as being someone elses voice Increased levels of activity in Brocas area during hallucinations problem in the connections between the frontal lobe areas(the pr
6、oduction of speech)and the temporal lobe areas(the understanding of speech)Negative Symptoms:Behavioral deficitslThese symptoms tend to endure beyond an acute episodelAvolition Lack of interest and drivelAlogia Poverty of speech Poverty of contentlAnhendonia Inability to experience pleasurelFlat aff
7、ect:66%Exhibits little or no affect in face or voicelAsociality Inability to form close personal relationships Beginning in childhood before the onset of other symptomsDisorganized SymptomslDisorganized speech Incoherence Inability to organize ideas Loose associations(derailment)Rambles,difficulty s
8、ticking to one topic Problem in executive functioning(problem solving,planning,and making associations between thinking and feeling)and in the ability to perceive semantic informationlDisorganized behavior Odd or peculiar behavior Silliness,agitation,unusual dressOther SymptomslCatatonia Motor abnor
9、malities Repetitive,complex gesturesUsually of the fingers,hands and arm movements Catatonic immobilityMaintain unusual posture for long periods of timele.g.,stand on one leg Waxy flexibilityanother person can move the patients limbs into positions that the patient will then maintain for long period
10、s of timeOther SymptomslInappropriate affect Emotional responses inconsistent with situatione.g.,laugh uncontrollably at a funeral;shift rapidly from one emotional state to another for no discernible reasonThis symptom is quite rareSpecific to schizophreniaCriteria for Schizophrenia in DSM-IV-TRlTwo
11、 or more of the following symptoms for at least 1 month:Delusions Hallucinations Disorganized speech Disorganized or catatonic behavior Negative symptomslSocial and occupational functioning have declined since onsetlSigns of disturbance for at least 6 months;Categories of Schizophrenia in DSM-IV-TRl
12、Disorganized schizophrenia Incoherence,disorganized speech and behavior Flat or inappropriate affectlCatatonic schizophrenia Prolonged immobility or purposeless agitation Seldom todaylParanoid schizophrenia Delusions,hallucinations related to persecution or grandiosity Grandiosity delusions:an exagg
13、erated sense of their own importance,power,knowledge,or identity.Ideas of reference:incorporate unimportant events within a delusional framework and read personal significance into the trivial activities of others e.g.,newscast on TV is about melUndifferentiated schizophrenia Meet criteria for schiz
14、ophrenia but not for any of the 3 main subtypeslResidual schizophrenia No longer meets full criteria for schizophrenia but still exhibits some signs of the disorderEvaluation of SubtypeslDiagnosis of subtypes difficult Reliability lowlPoor predictive validitylOverlap of symptoms among subtypes E.g.d
15、elusionsOther Psychotic DisorderslSchizophreniform Disorder Symptoms are the same as those of schizophrenia Symptom last only from 1 to 6 monthslBrief Psychotic Disorder Symptom duration of 1 day to 1 month Often triggered by extreme stressOther Psychotic DisorderslSchizoaffective Disorder Symptoms
16、of both mood disorder and schizophrenialDelusional Disorder Persistent delusions Persecution,jealousy,being followed,erotomania,somatic Non-bizarre delusions e.g.,jealousy,erotomania No other symptoms of schizophreniaEtiology of Schizophrenia:GeneticslNot likely that disorder caused by single genelB
17、ehavior genetics research Family studies&Twin studies(Table 11.2)The risk increases as the genetic relationship between proband and relative becomes closer MZ(44.3%)DZ(12.08%)Negative symptoms may have a stronger genetic component Adoption studies Table 11.3Etiology of Schizophrenia:GeneticslMolecul
18、ar genetics research Linkage studies A number of chromosomes implicated Results inconsistent and marked by a failure to replicate Association studies Two genes identifiedlDTNBP1:encoding a protein called dysbindinlNGR1:linked to the neurotransmitter glutamates receptors&the process of myelination Ta
19、ble 11.2 Family and Twin Genetic StudiesTable 11.3 Characteristics of Adopted Offspring of Mothers with SchizophreniaEtiology of Schizophrenia:Evaluation of Genetic ResearchlStrong genetic component Genetics doesnt completely explain the disorderlDiathesis-stress model Genetic factors constitute und
20、erlying predisposition Stress triggers onset lLimitations:Cans specify exactly how a predisposition for schizophrenia is transmitted The nature of the inherited diathesis remains unknown.Etiology of Schizophrenia:NeurotransmitterslDopamine Theory Disorder due to excess levels of dopamine Drugs that
21、alleviate symptoms reduce dopamine activity(block D2 receptors)Antipsychotic drugs produce side effects resembling the symptoms of Parkinsons disease(caused in part by low levels of dopamine)Amphetamines,which increase dopamine levels,can induce a psychosis(like paranoid schizophrenia)lTheory revise
22、d Excess numbers of dopamine receptors or oversensitive dopamine receptors in the mesolimbic pathway Dopamine abnormalities mainly related to positive symptoms Antipsychotics lessen positive symptoms but have little or no effect on negative symptomsFigure 11.1 The Brain and SchizophreniaFigure 11.2
23、Dopamine Theory of SchizophreniaEtiology of Schizophrenia:Evaluation of Dopamine TheorylDopamine theory doesnt completely explain disorder Antipsychotics block dopamine rapidly but symptom relief takes several weeks To be effective,antipsychotics must reduce dopamine activity to below normal levelsl
24、Other neurotransmitters involved:Serotonin GABA Glutamate Etiology of Schizophrenia:Brain Structure and Function lEnlarged Ventricles Implies loss of brain cells Correlate with Poor performance on cognitive tests Poor premorbid adjustment Poor response to treatment Not specific to schizophrenialRedu
25、ced activity in prefrontal cortex Involved in speech,executive functions,goal-directed behavior Reductions in gray matter in the prefrontal cortex May be related to dopamine underactivityEtiology of Schizophrenia:Brain Structure and FunctionlCongenital Factors Damage during gestation or birthObstetr
26、ical complications rates high in patients with schizophrenialReduced supply of oxygen during delivery may result in loss of cortical gray matter Viral damage to fetal brainIn Finnish study,schizophrenia rates higher when mother had flu in second trimester of pregnancy(Mednick et al.,1988)Etiology of
27、 Schizophrenia:Brain Structure and FunctionlDevelopmental Factors Prefrontal cortex matures in adolescence or early adulthood Dopamine activity also peaks in adolescence Excessive neuronal pruninglMay explain why symptoms appear in late adolescence but brain damage occurs early in lifeEtiology of Sc
28、hizophrenia:Psychological StresslSocioeconomic statuslHighest rates of schizophrenia among urban poor.Sociogenic hypothesis Stress of poverty causes disorder Social selection theory Downward drift in socioeconomic status lTurner&Wagonfield(1968)studied SES of patients fathers Results support social
29、selection hypothesis Etiology of Schizophrenia:psychological lFamily-related factors Schizophrenogenic mother Cold,rejecting,overprotective,domineering,conflict-inducingNo support for this theory Communication deviance(CD)Hostility and poor communicationlFamily CD predicted onset in one longitudinal
30、 study(Norton,1982)lCD not specific to families of schizophrenic patientsEtiology of Schizophrenia:psychologicallFamilies and Relapse Family environment impacts rehospitalization Expressed Emotion(EE;Brown et al.,1966)Hostility,critical comments,emotional overinvolvementRelapse rate:High EE(58%)Low
31、EE(10%)Bi-directional association lThe expression of unusual thoughts by the pt increased critical comments by family memberslCritical comments by family members increased expression of unusual thoughts by the ptEtiology of Schizophrenia:Developmental StudieslDevelopmental histories of children who
32、later developed schizophrenia(in the 1960s)Lower IQ More often delinquent and withdrawn lCoding of home movies Poorer motor skills More expression of negative emotionEtiology of Schizophrenia:Developmental StudieslHigh risk studies Danish children with a schizophrenic mother who later developed diso
33、rder(Mednick&Schulsinger,1968)Negative symptom patientslMore pregnancy birth complicationslFailure to show electrodermal responding Positive symptom patientslFamily instability Divorce or institutionalization Australian study(Yung et al.,1995)MRI found reduced gray matter volume predicted later deve
34、lopment of psychotic disorderTreatment of Schizophrenia:MedicationslTraditional antipsychotic drugs&their side effects Antipsychotic medications(1950s)Chlorpromazine(Thorazine),haloperidol(Haldol),lBlock dopamine receptorslReduce the positive and disorganized symptoms Side effects Dizziness,blurred
35、vision,restlessness,sexual dysfunction Extrapyramidal side effectslStem from dysfunctions of the nerve tracts that descend from the brain to spinal motor neurons;resemble the symptoms of Parkinsons diseaselTremors of the fingers,a shuffling gait,&droolinglDystonia,dyskinesiaTreatment of Schizophreni
36、a:MedicationslAtypical antipsychotic medications Clozapine(Clozaril)Fewer motor side effects Less likely to drop out of treatment Impact on serotonin receptorslSide effects Can impair immune symptom functioning in 1%pts by lowering the number of white blood cells Seizures,dizziness,fatigue,drooling,
37、weight gain Relate to type 2 DiabetesPsychological Treatments:Psychoanalytic therapylFreud Little value in psychotherapy for psychotic disorders Schizophrenics were incapable of establishing the close interpersonal relationship essential for analysislHarry Stack Sullivan Develop trusting therapist-p
38、atient relationship Teach adult forms of communication Foster insight into role of pastPsychological TreatmentslRecent types of psychosocial treatments are more active,present-focused,and reality-oriented lSocial skills training Teach effective social behaviorslFamily therapy to reduce EE Educate fa
39、mily about causes,symptoms,and signs of relapse Stress importance of antipsychotic medication Help family to avoid blaming patient Improve family communication and problem-solving Encourage expanded support networks Instill hope that things can improvePsychological TreatmentslCognitive behavioral therapy Recognize and challenge cognitive distortions Recognize and challenge expectations associated with negative symptoms e.g.,low expectations for success and pleasurelCognitive enhancement therapy(CET)Improve attention,memory,problem solving and other cognitive based symptoms
