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Learn about the symptoms, subtypes, and prevalence of schizophrenia. Understand the impact of this disorder on individuals and society.
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What is Schizophrenia? • Ability to function is impaired by severely distorted beliefs, emotions, perceptions, & thought processes • Comes from Greek meaning “split” and “mind” • ‘split’ refers to loss of touch with reality - psychosis • not dissociative state • not ‘split personality’ • 1 in 100 people develop schizophrenia • 24 million world wide
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.
Hallucinations – False Perceptions • Auditory - hearing voices • Most common • Command hallucinations: voices giving orders • Visual – seeing things not actually present • Tactile – feeling skin sensations • All of these contribute to delusions
Disorganized Symptoms • 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 • Maybe caused by a breakdown in selective attention • 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 • DSM 5 removed these subtypes and now uses a spectrum of severity to classify 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
Subtypes 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). • Online Version (8 min) • As you watch Gerald write down what symptoms you see him demonstrating. • What subtype of Schizophrenia would you predict he has?
DSM 5 removed these subtypes and now uses a spectrum of severity to classify schizophrenia. They are helpful though in remembering the different kinds of symptoms that can accompany the disorder.
Prevalence of Schizophrenia • Onset of schizophrenia typically occurs during young adulthood. • Males have earlier onset • 18 to 25 for men • 26 to 45 for women • Approximately 1.2% of Americans (3.2 million) have the disorder • 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 • Acute/Reactive Schizophrenia – develops rapidly usually after a stressful event. High rate of recovery • Chronic/ProcessSchizophrenia – develops slowly, often with negative symptoms, low recovery rate • 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 1/2, schizophrenia becomes a chronic mental illness, and the ability to function normally in society may be severely impaired.
The Dopamine Theory • Theory: Schizophrenia is caused by excess of receptors for dopamine • Potential cause for positive symptoms • Drugs that reduce dopamine reduce symptoms • Drugs that increase dopamine (amphetamines & cocaine) can 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 • Shrinkage found in cortex, corpus callosum, & thalamus • PET scans show reduced frontal lobe activity • Increased activity in Thalamus (filters incoming info) when experiencing hallucinations • Increased activity in Amygdala for those with paranoia
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 & 18
Not Just Brain Abnormalities 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
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 • One study found traces of retrovirus in nearly half of people with schizophrenia while finding virtually none in healthy people.
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.) • Maternal stress may “turn on” genes that predispose schizophrenia
Schizophrenia and Genetics Risk increases with genetic similarity 40 30 20 10 0 Lifetime risk of developing schizophrenia for relatives of a schizophrenic Children of two schizophrenia victims Fraternal twin Identical twin General population Siblings Children
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.)
Unhealthy Family Environment • 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 Dysfunctional Family variables: • parental communication that is disorganized, hard-to-follow, or highly emotional • expressed emotion • highly critical, over-enmeshed families
Possible Early Warning Signs of Schizophrenia • A mother whose schizophrenia severe & long lasting • Birth complications – oxygen deprivation or low birth weight • Separation from parents • Short attention span & poor muscle coordination • Disruptive or withdrawn behavior • Emotional unpredictability • Poor peer relations or solo play
Development Model of Schizophrenia This 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)
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?
