Schizophrenia - summary of chapter 9 of Abnormal Psychology by Kring, Davison, Neale & Johnson (12th edition)

Clinical psychology
Chapter 9
Schizophrenia

Schizophrenia: a disorder characterized by disturbances in thought, emotion and behavior.

>1% prevalence
Slightly more men than women.
Sometimes develops in childhood, but usually appears in late adolescence or early adulthood
people with schizophrenia typically have a number of episodes of their symptoms and less severe but still debilitating symptoms between episodes.

Clinical descriptions of schizophrenia

The range of symptoms in the diagnosis of schizophrenia is extensive, although people with schizophrenia typically have only some of these problems at any given time.
No single essential symptom must be present for a diagnosis of schizophrenia.

Researchers divided symptoms in three

• Positive symptoms
  Delusions, hallucinations
• Disorganized symptoms
  Disorganized behavior, disorganized speech
• Negative symptoms
  Avolition, alogia, anhedonia, blunted affect, asociality

DSM-5 criteria of schizophrenia

• Two or more of the following symptoms for at least 1 month; one symptom should be either 1, 2, or 3:
  1. delusions
  2. hallucinations
  3. disorganized speech
  4. disorganized (or catatonic) behavior
  5. negative symptoms (diminished motivation or emotional expression)
• Functioning in work, relationships, or self-care has declined since onset
• Signs of disorder for at least 6 months; or, if during a prodromal or residual phase, negative symptoms or two or more of symptoms 1-4 in less severe form.

Positive symptoms

Positive symptoms comprise excesses and distortions, such as hallucinations and delusions.
For the most part, acute episodes of schizophrenia are characterized by positive symptoms.

Delusions

Delusions: beliefs contrary to reality and firmly held in spite of disconfirming evidence.
Common symptoms in schizophrenia.

Delusions take several forms including:

• Thought insertion: the belief that thoughts that are not his or hers own have been placed in his or her mind by an external force.
• Thought broadcasting: the believe that his or her thoughts are broadcast or transmitted, so that other know what the person is thinking
• The believe that an external force controls his or her feelings or behaviors
• Grandiose delusions: an exaggerated sense of his or her own importance, power, knowledge, or identity.
• Ideas of reference: incorporating unimportant events within a delusional framework and reading personal significance into the trivial activities of others.

Delusions are also found in other diagnoses,

• Bipolar disorder
• Depression with psychotic features
• Delusional disorder

Hallucinations and other disturbances of perception

Hallucinations: sensory experiences in the absence of any relevant information for the environment.
More often auditory than visual.

Negative symptoms

The negative symptoms of schizophrenia consists of behavioral deficits.
Include:

• Avolition
• Asociality
• Anhedonia
• Blunted affect
• Alogia

Negative symptoms tend to endure beyond an acute episode and have profound effects on the lives of people with schizophrenia.
The presence of many negative symptoms is a strong predictor of a poor quality of life.

Avolition

A lack of motivation and a seeming absence of interest in or an inability to persist in what are usually routine activities, including work or school, hobbies, or social activities.

Asociality

Severe impairments in social relationships.
They may wish to spend much of their time alone.

Anhedonia

Anhedonia: a loss of interest in or a reported lessening of the experience of pleasure.
Two types o of pleasure experiences in the anhedonia construct:

• Consummatory pleasure:
  The amount of pleasure experienced in-the-moment or in the presence of something pleasurable.
• Anticipatory pleasure:
  The amount of expected or anticipated pleasure from future events or activities.

People with schizophrenia appear to have a deficit in anticipatory pleasure but not consummatory pleasure.

Blunted affect

A lack of outward expression of emotion.
Only the outward expression of emotion, not the patient’s inner experience, which is not impoverished at all.

People with schizophrenia report experiencing the same amount or even more emotion than people without schizophrenia.

Alogia

A significant reduction in the amount of speech.

Disorganized symptoms

Include disorganized speech and disorganized behavior

Disorganized speech

Problems in organizing ideas and in speaking so that a listener can understand.

• Incoherence
• Loose associations or derailment
  The person may be more successful in communicating with a listener but has difficulty sticking to one topic.

Disorganized speech is associated with problems in executive functioning. Also related to the ability to perceive semantic information.

Disorganized behavior

Takes many forms.
They seem to lose the ability to organize their behavior and make it conform to community standards. They also have difficulty performing the tasks of everyday living.

Movement symptoms

Disturbances in movement behavior: grossly abnormal psychomotor behavior.

Catatonia: unusual increase in their overall level of activity, including much excitement, wild flailing of the limbs, and great expenditure of energy similar to that seen in mania.
Catatonic immobility: people adopt unusual postures and maintain them for very long periods of time.

Waxy flexibility: another person can move the patient’s limbs into positions that the patient will then maintain for long periods of time.

Schizophrenia and the DSM-5

Schizophreniform disorder: the same as schizophrenia, but lasts from 1 to 6 months
Brief psychotic disorder: from 1 day to 1 month. Often brought by extreme stress.
Must include hallucinations, delusions, or disorganized speech

Delusional disorder: troubled by persistent delusions of persecution or by delusional jealousy.

Etiology of schizophrenia

Genetic factors

Schizophrenia has a genetic component.
Schizophrenia is genetically heterogeneous, genetic factors can vary from case to case.

Behavior genetics research

Genetics play a role
Negative symptoms have a stronger genetic component than do positive symptoms.

Familial high-risk study: begins with one or two biological parents with schizophrenia and follows their offspring longitudinally in order to identify how many of these children may develop schizophrenia.

Positive and negative symptoms may have different etiologies.

Molecular genetics research

The predisposition of schizophrenia is not transmitted by a single gene.

Genetic vulnerability to schizophrenia may be made up of many rare mutations.

The role of neurotransmitters

Dopamine theory

An excess in dopamine. Way to much

An excess of dopamine receptors appears to be related mainly to positive symptoms.

Other neurons

Glutamine may also play a role.

Brain structure and function

Enlarged ventricles

Factors involving the prefrontal cortex

• The prefrontal cortex is known to play a role in behaviors such as speech, decision making, emotion, and goal-directed behavior, which are disrupted in schizophrenia.
• Reductions in gray matter in the prefrontal cortex
• Failure to show frontal activation is related to the severity of negative symptoms and thus parallels the work on dopamine under-activity in the frontal cortex.

The number of neurons do not appear to be reduced. Loss dendritic spines.

Problems in the temporal cortex and surrounding regions

People with schizophrenia have structural and functional abnormalities in the temporal cortex.
Reduced hippocampus volume, may reflect a combination of genetic and environmental factors.
Stress reactivity and a disrupted HPA (hippocampic-pituitary-adrenal) axis likely contribute to the reductions in hippocampal volume.

Environmental factors influencing the developing brain

• Damage during gestation or birth increases the risk
• Maternal infections during pregnancy

Why late?

• Prefrontal cortex develops late
• Dopamine activity peaks in adolescence
• Loss of synapses due to excessive pruning
• Cannabis use

Psychological factors

People with schizophrenia appear to be very reactive to the stressors we encounter in daily life.

Socioeconomic status and urban living

There is a sharp upturn in the prevalence of schizophrenia in people of the lowest socioeconomic status.

Social selection hypothesis: people with schizophrenia drift into poor neighborhoods because their illness impairs their earning power and they cannot afford to live elsewhere.

Sociogenetic hypothesis: stressors associated with socioeconomic status and urban living contribute to the development of schizophrenia

Research is more supportive of the social selection hypothesis

Family-related factors

Some role for the family.

Family can have an important impact on the adjustment of people with schizophrenia after they leave the hospital.

Expressed emotion (EE)
In high-EE families, critical comments by family members led to increased expression of unusual thoughts by people with schizophrenia. And unusual thoughts expressed by the relatives with schizophrenia led to increased critical comments.

Developmental factors

Retrospective studies

• Poorer motor skills
• More expressions of negative emotions
• Lower on IQ

Prospective studies

• Lower scores in IQ test in childhood predicted the onset of schizophrenia in young adulthood
• Lower gray matter volumes

Treatment of schizophrenia

Treatments for schizophrenia most often include a combination of short-term hospital stays, medication, and psychosocial treatment.

• Some people with schizophrenia lack insight into their impaired condition and refuse any treatment at all

Medications

First-generation antipsychotic drugs and their side effects

Some symptoms may go away, but lives are still not fulfilling for many people with schizophrenia.
Commonly reported side effects of all antipsycotics include:

• Sedation
• Dizziness
• Blurred vision
• Restlessness
• Sexual dysfunction
• Tardive dyskinesia: the mouth involuntary make sucking, lip-smackingm and chin-wagging motions
• Neuroleptic maligant syndrome: severe muscular rigidity develops, accompanied with fever.

Second-generation antipscyhotic drugs and their side effects

Psychological treatments

Social skills training

Teach people with schizophrenia how to successfully manage a wide variety of interpersonal situations.
Typically involves role-playing and other group exercises to practice skills, both in a therapy group and in actual social situations.

Family therapies

• Education about schizophrenia, specifically about the genetic and neurobiological factors that predispose some people to the illness, the cognitive problems associated with schizophrenia, the symptoms of schizophrenia, and the signs of impending relapse.
• Information about antipsychotic medication
• Blame avoidance and reduction
• Communication and problem-solving skills within the family
• Social network expansion
• Hope

Cognitive behavior therapy

The maladaptive beliefs of some people with schizophrenia can benefit from cognitive behavior therapy.

• Can reduce negative symptoms
• Can help reduce hallucinations and delusions

Cognitive remediation therapies

Enhance basic cognitive functions.

Cognitive training improved symptoms and functional outcomes.

Psychoeducation

Effective in reducing relapse