schizophrenia. what is schizophrenia? ability to function is impaired by severely distorted beliefs,...

Schizophrenia

What is Schizophrenia?• Ability to function is impaired by

severely distorted beliefs, perceptions, and thought processes

• Comes from Greek meaning “split” and “mind” – ‘split’ refers to loss of touch with reality– not dissociative state– not ‘split personality’

• Equally split between genders, males have earlier onset– 18 to 25 for men– 26 to 45 for women

Symptoms of Schizophrenia• Positive symptoms

– Excess of or distortion of normal functions• Hallucinations – false perceptions (auditory or visual)

• Delusions – false beliefs

• Negative symptoms– absence of normal cognition or affect

• flat affect – emotionally “flat”

• alogia - poverty of speech

• avolition – inability to do simple goal-directed behaviors (dressing, bathing, social activities)

• Disorganized Symptoms– Disorganized Speech or Behavior

Disorganized Speech• Word Salad - a string of words that vaguely resembles language, and

may or may not be grammatically correct, but is utterly meaningless.– “Tramway flogging into my question, are you why is it thirty

letters down under peanut butter, what is it.”– Watch this example from Boston Legal (1 min)

• Neologisms - Making up words – “I am going to the park to ride the wallywhoop.”

• Clang Speech - Rhyming all the words . – “Deck the halls with boughs of holly, folly, polly, dolly, hello

Dolly, want a lollipop?”• Echolalia - Repeating exactly what someone else has said • Echopraxia - Repeating exactly what someone else has done.

Disorganized Behavior

• Perseveration - Repeating the same activity (word or behavior) over and over again.

• Dressing oddly, such as wearing many sets of clothing one over the other or wearing hats, gloves, and heavy coats in the summer.

• Doing things in public that are usually done only in private. For example: urinating on a street corner.

Common Delusions• Delusions of reference - believes that other people are

constantly talking about her or that everything that happens is somehow related to her

• Delusions of persecution - believes that others are plotting against or trying to harm him or someone close to him – ‘they’re out to get me’– paranoia

• Delusions of grandeur - believes he is extremely important, powerful, or wealthy. – “God” complex– megalomania

• Delusions of being controlled– the CIA is controlling my brain with a radio signal

Symptoms of Schizophrenia• Hallucinations

– hearing or seeing things that aren’t there (most common are auditory)

– contributes to delusions– command hallucinations: voices giving orders

• Disorganized thought– Over-inclusion—jumping from idea to idea without the benefit

of logical association– Paralogic—on the surface, seems logical, but seriously flawed

• e.g., Jesus was a man with a beard, I am a man with a beard, therefore I am Jesus

• Disturbances in sensation – sights, sounds, and other sensations feel distorted

Symptoms of Schizophrenia

• Disorganized behavior and affect– behavior is inappropriate for the situation

• e.g., wearing sweaters and overcoats on hot days

– affect is inappropriately expressed• flat affect—no emotion at all in face or speech• inappropriate affect—laughing at very serious things,

crying at funny things

– catatonic behavior• unresponsiveness to environment, usually marked by

immobility for extended periods

Frequency of positive and negative symptoms in individuals at the time they were hospitalized for schizophrenia. Source: Based on data reported in Andreasen & Flaum, 1991.

Subtypes of Schizophrenia

• Paranoid type– delusions of persecution

• believes others are spying and plotting

– delusions of grandeur• believes others are jealous, inferior, subservient

– no cognitive impairment, disorganized behavior, or negative symptoms

• Catatonic type—unresponsive to surroundings, purposeless movement, parrot-like speech– waxy flexibility – highly disturbed movements or actions

Types of Schizophrenia

• Disorganized type– delusions and hallucinations with little meaning– disorganized speech, behavior, and flat affect

• Undifferentiated type – exhibits symptoms of schizophrenia but can’t be fit into one of the 3 subtypes.

Schizophrenia: An Example

• Watch Module 26 from The Brain dvd (5 min).

• As you watch Gerry write down what symptoms you see him demonstrating.

Prevalence of Schizophrenia

• Onset of schizophrenia typically occurs during young adulthood.

• Approximately 1 million Americans are treated for schizophrenia annually

• Worldwide, about 1% of the population will experience at least one episode of schizophrenia at some point in life

Course of Schizophrenia:The ¼, ¼, ½ Rule

• Enormous individual variability

• About 1/4 of those who experience an episode of schizophrenia recover completely; another 1/4 experience recurrent episodes, but often with only minimal impairment of functioning

• The other one-half, schizophrenia becomes a chronic mental illness, and the ability to function normally in society may be severely impaired.

Schizophrenia and GeneticsRisk increases with genetic similarity

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Developing Schizophrenia

The lifetime risk of developing schizophrenia varies with one's genetic relatedness to someone having this disorder. Across countries, barely more than 1 in 10 fraternal twins, but some 5 in 10 identical twins, share a schizophrenia diagnosis. (Adapted from Gottesman, 2001.)

The Heritability of Schizophrenia

The researchers looked for signs of schizophrenia in the biological and adoptive relatives of people who had been adopted at an early age and either did or did not subsequently develop schizophrenia. The results here are the percentage of relatives who showed either schizophrenia or a milder disorder now called schizotypal personality disorder. (Data from Kety & others, 1976.)

POSSIBLE BIOLOGICAL

FACTORS

Paternal age: Older fathers and the risk of

schizophrenia • Because schizophrenia often occurs in

individuals with no family history of mental disorders, no genetic model explains all the patterns of schizophrenia

• Researchers in Jerusalem reviewed data on 87,000 people and found that paternal age was a strong and significant predictor of the schizophrenia diagnosis. (Mother’s age appeared to play no role.)

• Paternal age failed to account for three-quarters of the cases of schizophrenia.

Biological Bases of Schizophrenia

• Other congenital influences– difficult birth (e.g., oxygen deprivation)

– prenatal viral infection

• Brain chemistry– neurotransmitter excesses or deficits

– dopamine theory

The Dopamine Theory

• Theory: Schizophrenia is caused by excess dopamine

• Drugs that reduce dopamine reduce symptoms

• Drugs that increase dopamine produce symptoms even in people without the disorder

• Dopamine theory not enough; other neurotransmitters involved as well

Other Biological Factors

• About half the people with schizophrenia show some type of brain structure abnormality

• Brain structure and function– enlarged cerebral ventricles and reduced neural tissue around

the ventricles– PET scans show reduced frontal lobe activity

• Early warning signs– nothing very reliable has been found yet– certain attention deficits can be found in children who are at

risk for the disorder

Brain Activity & Tissue Loss• One five-year prospective study compared brain structure

changes in normal adolescents and adolescents with early onset schizophrenia

• Gray matter tissue loss ranged from about 1 percent in the normal teens to more than 5 percent in the schizophrenic teens

• The amount of gray matter loss was directly correlated to the teenage patient’s clinical symptoms – More rapid gray matter losses in the temporal lobes were

associated with more severe positive symptoms – More rapid gray matter losses in the frontal lobes were

strongly correlated with the severity of negative symptoms

• PET scans of brain activity during schizophrenic hallucinations reveal activity in the left auditory and visual areas of the brain, but not in the frontal lobe, which is normally involved in organized thought processes.

The Shrinking of the Schizophrenic Brain

Among adolescents who suffer a relatively rare childhood - onset schizophrenia, MRI scans by Paul Thompson and his colleagues (2001) revealed a much-greater-than-normal loss of cerebral cortex tissue between the ages of 13 and 18

Doctors view X-rays of the brains of identical twins, one of whom has schizophrenia. The X-ray of the schizophrenic twin shows shrinkage of the brain tissue and an accumulation of cerebrospinal fluid.

The Schizophrenic Brain

Click HERE or on the box to the Right to view.

The Schizophrenic Brain: Questions

1. What does the difference in brain structures of these identical twins indicate about the cause of brain abnormality and schizophrenia in this case?

2. Research suggests that prenatal viral infection may play a role in schizophrenia. Suggest some ways in which this hypothesis could be tested.

3. What types of studies could look into the possible genetic factors in development of schizophrenia?

Not Just Biology at Fault

• Some people with schizophrenia do not show brain structure abnormalities

• The evidence is correlational • The kinds of brain abnormalities

seen in schizophrenia are also seen in other mental disorders

POSSIBLE ENVIRONMENTAL

FACTORS

Viral Infection Theory

• Might be caused by exposure to an influenza virus or other viral infection during prenatal development or shortly after birth

• Children whose mothers were exposed to a flu virus during the second trimester of pregnancy show an increased rate of schizophrenia

• Schizophrenia occurs more often in people who were born in the winter and spring months, when upper respiratory infections are most common

Malnutrition & Schizophrenia

Children who were in their mothers' wombs during the period of great famine in China later developed schizophrenia at roughly twice the usual rate. (Data from St. Clair & others, 2005.)

POSSIBLE PSYCHOLOGICAL

FACTORS

Unhealthy Families

• Individuals who are genetically predisposed to develop schizophrenia may be more vulnerable to the effects of disturbed family environments

Finnish Adoptive Family Study of Schizophrenia

• Found that children whose biological mother had schizophrenia had a much higher rate of schizophrenia than did the control group when they were raised in a psychologically disturbed adoptive family

• When raised in a psychologically healthy adoptive family, they were no more likely than the control group to develop schizophrenia.

• One-third of the adopted children with no genetic history of schizophrenia developed symptoms of a serious psychological disorder if they were raised in a psychologically disturbed family environment

• Conclusion: a healthy psychological environment may counteract a person’s inherited vulnerability for schizophrenia, but a psychologically unhealthy family environment can act as a catalyst for the onset of schizophrenia

Other Family Influences on Schizophrenia

Family variables– parental communication that is

disorganized, hard-to-follow, or highly emotional

– expressed emotion• highly critical, over-enmeshed families

Cultural Differences in Schizophrenia

• Prevalence of symptoms is similar no matter what the culture

• Less industrialized countries have better rates of recovery than industrialized countries– families tend to be less critical of the patients– less use of antipsychotic medications, which may impair

full recovery– think of it as transient, rather than chronic and lasting

disorder

Development Model of SchizophreniaThis model depicts researchers' understanding of the contributions of genes, environmental experiences, and the person's present neural and behavioral condition to the development of schizophrenia and, in some cases, its progression into a chronic condition. (Based on a model depicted by Tsuang & others, 2001, p. 22.)

Summary of Schizophrenia

• Many biological factors seem involved– heredity– neurotransmitters– brain structure abnormalities

• Family and cultural factors also important• Combined model of schizophrenia

– biological predisposition combined with psychosocial stressors leads to disorder

– Is schizophrenia the maladaptive coping behavior of a biologically vulnerable person?