Transcript abnormal PSYCHOLOGY Third Canadian Edition

abnormal
PSYCHOLOGY
Third Canadian Edition
Chapter 11
Schizophrenia
Prepared by:
Tracy Vaillancourt, Ph.D.
Schizophrenia
• Psychotic disorder characterized by major
disturbances in thought, emotion, and
behaviour
– disordered thinking in which ideas are not
logically related
– faulty perception and attention
– flat or inappropriate affect
– bizarre disturbances in motor activity
Prevalence and Comorbidity
• Prevalence = 1% of general population
– usually appears in late adolescence or early
adulthood
– appears earlier for men than for women
• Comorbid Conditions
– substance abuse (70%)
– depression (40%)
– anxiety disorders
Clinical Symptoms
Positive Symptoms
• Excesses or distortions
• Delusions
• Hallucinations
Negative Symptoms
• Behavioural deficits
Positive Symptoms
• Excesses or distortions
– Disorganized speech
• problems in organizing ideas and in speaking so that a
listener can understand
• loose associations
• derailment
• Delusions
• Hallucinations
Negative Symptoms
• Behavioural deficits
– Avolition
• lack of energy
– Alogia
• poverty of speech, amount of speech, poverty of content of
speech etc.
– Anhedonia
• lack of interest in recreational activities, relationships with
others and sex
– Flat affect
– Asociality
• few friends, poor social skills, and little interest in being with
others
Other Symptoms
• Catatonia
– catatonic immobility
– waxy flexibility
• Inappropriate affect
Summary
Early Descriptions of Schizophrenia
• Concept formulated by Emil Kraepelin and
Eugen Bleuler
• Kraepelin first presented his notion of dementia
praecox
– differentiated two groups of endogenous psychoses
• manic-depressive illness
• dementia praecox
– dementia paranoides, catatonia, and hebephrenia
• Bleuler broke with Kraepelin on 2 major points:
– did not believe in early onset
– did not believe in inevitably progress toward dementia
• proposed own term— schizophrenia
Categories of Schizophrenia
• Disorganized schizophrenia
• Catatonic schizophrenia
• Paranoid schizophrenia
– grandiose delusions
– delusional jealousy
– ideas of reference
• Undifferentiated schizophrenia
– person does not meet the criteria for any of the above types
• Residual schizophrenia
– no longer meets full criteria for schizophrenia but still shows
some signs of illness
Etiology: Genetic Data
Etiology: Molecular Genetics
• Not likely transmitted by a single gene
• Now using “endophenotypic strategy”
– Endophenotypes – characteristics that reflect actions
of genes predisposing individual to a disorder, even in
the absence of diagnosable pathology (Turetsky et al., 2007,p. 69)
• assumed to be determined by fewer genes than the more
complex schizophrenia phenotype
– Some examples:
•
•
•
•
serotonin type 2A receptor (5—HT2a) gene
dopamine D3 receptor gene
chromosomal regions on chromosomes 6, 8, 13, and 22,
microdeletion on chromosome 22ql1
The Genain Quadruplets
Dopamine Theory
• Schizophrenia thought to be related to > activity
of dopamine
– drugs effective in treating schizophrenia  dopamine
activity
– also produce side effects similar to Parkinson’s
disease which is caused in part by  dopamine
– other clues provided by amphetamine psychosis
• closely resembles paranoid schizophrenia and can
exacerbate symptoms of schizophrenia
• amphetamines cause release of norepinephrine
and dopamine
– dopamine thought to be the culprit of the symptoms
Brain Structure and Function
• Enlarged Ventricles
– enlarged ventricles which implies a loss of subcortical brain cells
• Structural problems
– in subcortical temporal-limbic areas, such as hippocampus and
basal ganglia, and prefrontal and temporal cortex
• Prefrontal cortex
– known to play a role in behaviours such as speech, decisionmaking, and willed action all of which are disrupted in
schizophrenia
• Note. MRI studies have shown reductions in grey matter in the
prefrontal cortex
Other Etiologies
• Psychological Stress
–  in life stress  the likelihood of a relapse
• Social class and schizophrenia
–  t rates of schizophrenia found in central city areas
inhabited by people in the → socio-economic class
• sociogenic hypothesis
• social-selection theory
• Family and Schizophrenia
– Schizophrenogenic mother
Biological Treatments
• Shock and Psychosurgery
– prefrontal lobotomy
• Drug Therapies
– Antipsychotic drugs (aka neuroleptics)
• First Generation (Conventional) Antipsychotic
Drugs
– primarily target D2 receptors
• Second Generation (Atypical) Antipsychotics
– primarily target D3 and D4 receptors
Summary of Major Drugs
Psychological Treatments
• Social Skills Training
• Family Therapy and Reducing Expressed
Emotions
• Cognitive-Behavioural Therapy
• Personal Therapy
• Treatment Focus on Basic Cognitive
Functions
– cognitive enhancement therapy
Other Issues
• Homelessness
• Employment and Housing
• Substance Abuse
– Note. Lifetime prevalence rate for substance
abuse among people with schizophrenia is
50%
• Stigmatization
Copyright
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