Schizophrenia and Other Psychotic Disorders (Chapter 13)

Schizophrenia

• first clinical description appeared in 1810

• originally used the term “dementia praecox” to refer to mental deterioration at an early age

• Eugen Bleuler introduces the term “schizophrenia” in 1911

  • from Greek meaning “ to split or crack” and “mind”

Psychosis

• significant loss of contact with reality

  • hallmark of schizophrenia

Schizophrenia — Prevalence and Gender Differences

• lifetime prevalence = around 0.7%

• more common and more severe in men

Schizophrenia — Age of Onset

• 18-30

Schizophrenia — Risk Factors

• age of father (over 50)

  • at older ages men’s sperm is more likely to have deficits in DNA

• parent in dry cleaning business

  • exposure to harsh chemicals

• first-generation and second-generation immigrants

  • parental stress

Schizophrenia — Delusions

• an erroneous belief that is fixed and firmly held despite clear contradictory evidence

  • disturbance in the content of thought

• ex; being controlled by external agents

  • private thoughts being broadcasted to others

  • thoughts have been inserted by external agency

  • thoughts withdrawn by external agency

• natural environmental event (TV, radio) have special meaning intended for one person

• delusions of bodily changes or removal of organs

Schizophrenia — Hallucinations

• sensory experience that seems real to the person having it, but in the absence of any external perceptual stimulus

• can occur in any sensory modality

• auditory are most common

• patients become emotionally involved with hallucinations

  • incorporate them into delusions

Schizophrenia — Disorganized Speech

• disorder in thought form

  • delusions are a disorder of thought content

• fail to make sense even though they are using language in a controversial way

  • words and combinations sound communicative

  • listener is left with a lack of understanding

  • may make up new words (neologisms)

Schizophrenia — Disorganized Behaviour

• impairment of goal-directed activity

• occurs in areas of daily functioning

  • ex; hygiene, silliness, or unusual dress

• catatonia

• catatonic stupor

Catatonia

• almost no movement at all, sometimes in an unusual posture

Catatonic Stupor

• a virtual absence of all movement and speech

Schizophrenia — Positive Symptoms

• excess or distortion in normal behaviour and experience

Schizophrenia — Negative Symptoms

• reflect an absence or deficit of normally present behaviours

  • 2 domains

  • reduced expressive behaviour

    • voice, facial expression, speech

    • blunted or flat affect, or alogia (little speech)

  • reductions in motivation or experience of pleasure

    • avolition

  • presence of negative symptoms is not a good sign

• agnosia

Avolition

• the inability to initiate or persist in goal-directed activity

Agnosia

• lack of insight — they don’t think they’re ill

Other Psychotic Disorders

• Schizoaffective Disorder

• Schizophreniform Disorder

• Delusional Disorder

• Brief Psychotic Disorder

Schizoaffective Disorder

• features of schizophrenia and severe mood disorder

• diagnostic criteria revised in DSM-5-TR to improve reliability

• ex;

  • Bipolar Type

  • Depressive Type

Schizoaffective Disorder — Bipolar Type

• psychotic symptoms present between episodes of mania/depression

Schizoaffective Disorder — Depressive Type

• psychotic symptoms present between episodes of depression

Schizophreniform Disorder

• schizophrenia-like psychosis lasting at least 1 month but less than 6 months (if it lasts more than 6 months — diagnosis gets moved to schizophrenia)

Delusional Disorder

• delusional beliefs with otherwise normal behaviour

• erotomania delusion involves great love for a person, usually of higher status

  • ex; baby reindeer stalker, conspiracy theorists

Brief Psychotic Disorder

• sudden onset of psychotic symptoms or disorganized speech or catatonic behaviour lasting only a matter of days

Schizophrenia — Genetic Factors

• tend to run in families

  • prevalence in first-degree relatives = 10%

  • prevalence in second-degree relatives = closer to 3%

Schizophrenia — Twin Studies

• concordance rates for identical twins = 28%

• concordance rates for nonidentical twins = 6%

*suggests mixture of genetic and nongenetic influences

Schizophrenia — Adoption Studies

• higher rates in adopted children who had schizophrenic biological children

Schizophrenia Risk Factors — The Quality of the Adoptive Family

• children at high genetic risk who were raised in healthy family environments did not develop problems any more frequently than children with a low genetic risk

  • evidence of genotype-environment interaction in schizophrenia

Schizophrenia Risk Factors — Molecular Genetics

• probably involves many genes working together

  • candidate genes

  • endophenotypes

Candidate Genes

• genes that are involved in processes that are believed to be aberrant in schizophrenia

Endophenotypes

• discrete, stable, and measurable traits that are thought to be under genetic control

Schizophrenia Risk Factors — Parental Exposures

• viral infection

• rhesus incompatibility

Schizophrenia Risk Factors — Pregnancy and Birth Complications

• early nutritional deficiency

• maternal stress

Schizophrenia Risk Factors — Genes and Environment

• the focus on MZ concordance rates causes an overestimate of the heritability of schizophrenia

  • chronic arrangements could mean different environments

  • around 2/3 of MZ embryos are monochorionic (share a placenta and blood supply)

• genetic liability to schizophrenia may predispose an individual to suffer more from the environment than those without the genetic predisposition

Schizophrenia — Neurodevelopmental Perspective

• the stage is set early in life

  • problems may not appear until the brain is mature

• research focuses on those showing prodomal (very early signs) of schizophrenia

• attenuated psychosis syndrome is not part of DSM-5 as a disorder in need of further study

Schizophrenia — Neurocognition

• cognitive impairment is a core feature of schizophrenia

  • apparent even before there is a diagnosable illness

• lower IQ may be a risk factor; higher IQ may be a protective factor

  • people with high IQ can stop psychotic symptoms without medication — do reality testing on themselves to test if delusions/hallucinations are real or not

• patients with schizophrenia are not able to respond to a stimulus as quickly and appropriately

• deficits are apparent in the earliest stages of visual and auditory processing

Schizophrenia — Social Cognition

• how we recognize, think about, and respond to social information, including the emotions and intentions of others

• people with schizophrenia show significant impairments in social cognition

  • failure to spot the kinds of subtle social hints

  • difficulty recognizing emotion in faces and emotion being conveyed in speech

Schizophrenia — Loss of Brain Volume

• patients with schizophrenia have enlarged brain ventricles (indicates brain is shrinking)

  • males are more affected than females

  • indicator of a reduction in brain tissue

• decrease in brain volume is present in very early stages

• progressive brain deterioration continues for many years

*most other disorders do not show physiological brain differences

Schizophrenia — Affected Brain Areas

• reductions in the volume of regions in the frontal and temporal lobes

  • more specifically, in the volume of medial temporal areas: the amygdala, the hippocampus and the thalamus

• brain structure is abnormal, but the abnormality is linked to

  • stage of illness

  • use of medications

  • other factors

Schizophrenia — White Matter Problems

• white matter is crucially important for the connectivity of the brain

  • white matter abnormalities have been shown to be correlated with cognitive impairments

• patients have reductions in white matter volume as well as structural abnormalities in the white matter itself

  • abnormalities are found in first-episode patients and in people at high genetic risk for the disorder

  • dysconnectivity: abnormal integration between distinct brain regions, particularly those involving the frontal lobes

Schizophrenia — Brain Functioning

• some patients show abnormally low frontal lobe activation (hypofrontality) when they are involved in mentally challenging tasks

• dysfunction of the temporal lobes is also found

  • may be a problem with how activity in different brain regions gets coordinated

Schizophrenia — Cytoarchitecture

• if cells fail to migrate properly, the overall organization of cells in the brain (the brain’s cytoarchitecture) will be comprimised

  • increase in neuronal density in some areas of the brains of patients

• abnormalities in the distribution of cells in the cortex and hippocampus

• patients with schizophrenia are missing “inhibitory interneurons”

  • may be less able to regulate or dampen down overactivity in certain neuronal circuits

Schizophrenia — Brain Development in Adolescence

• major brain changes take place during adolescence, as the brain matures

  • if problems occur, schizophrenia may be the result

• people who were in the hospital for a head injury have a 65% increased risk for schizophrenia

  • if a head injury occurs between the ages of 11 and 15, the risk of schizophrenia is increased by 85%

Schizophrenia — Neurochemistry

• alterations in brain chemistry might be associated with abnormal states

Dopamine in Schizophrenia

• a neurotransmitter that links things together — if you have a lot of dopamine you might see connections where there are none

  • chloropromazine blocks dopamine receptors and helps patients

  • amphetamines produce excess dopamine and mimic a psychotic state that looks like schizophrenia

  • L-DOPA treated patients display psychotic symptoms

Glutamate in Schizophrenia

• an excitatory neurotransmitter

  • when glutamate receptors are blocked it creates schizophrenic like symptoms

Do Bad Families Cause Schizophrenia?

• popular theories in the past blaming the family do not have empirical support

• if the child is not at genetic risk for schizophrenia, adverse family environments and communication deviance have little consequence

Schizophrenia — Expressed Emotion

• Expressed Emotion (EE)

  • 3 main effects

    • criticism

    • hostility

    • emotional overinvolvement (EOI)

• high EE home environment more than doubles the chance of a relapse — especially strong for chronically ill patients

• researchers are still trying to understand how EE affects the brain

Schizophrenia — Urban Living

• 1 study showed children who spend the first 15 years of life in an urban setting were 2.75x more likely to develop schizophrenia than those in rural settings

  • because urban environments are more stressful and overstimulating

• it is estimated that if we all lived in relatively rural settings the number of schizophrenia cases could decrease by 30%

Schizophrenia — Immigration

• recent immigrants have a much higher risk

• there is no evidence that this can be explained by cultural misunderstandings

• immigrants with darker skin have a much higher risk of developing schizophrenia than those with lighter skin

• healthy people who feel discriminated against are more likely to develop psychotic symptoms

Schizophrenia — Cannabis Use and Abuse

• people with schizophrenia are twice as likely to smoke cannabis as people in the general population

  • this could be a correlate and not a cause

  • the majority of cannabis users never develop schizophrenia

• cannabis may accelerate the progressive brain changes that seem to go along with schizophrenia

  • more brain volume decline if using cannabis (only correlational evidence)

    • possible that people who are more likely to smoke already had worse symptoms

A Diathesis-Stress Model of Schizophrenia

• biological factors play a role

  • genetic predispositions are shaped by environmental factors such as prenatal exposures, infections and stressors

• no simple answer to what causes schizophrenia

  • genetics and environment combine in such a way that brain pathways develop abnormally

Schizophrenia — Nongenetic Risk Factors

• older father (>50)

• head injuries

• virus exposure

• cannabis use

• obstetric complications

• urban upbringing

• migrant status

Schizophrenia — Early Signs

• young children who later developed schizophrenia had abnormal motor movements in childhood testing

  • because dopamine is involved in motor movements and schizophrenia

Schizophrenia — Clinical Outcome

• around 38% of patients have a favourable outcome and can be thought of as being recovered 15-25 years after development of the disorder

  • they do not return to how they were before they became ill

• around 12% of patients need long-term institutionalization

• around 1/3 show signs of continued negative symptoms — even with medication

• patients who live in less industrialized countries do better

Schizophrenia — Pharmacological Approaches

• first-generation antipsychotics

• second-generation antipsychotics

• other approaches

Schizophrenia Pharmacological Treatments — First-Generation Antipsychotics

• block the action of dopamine and treat positive symptoms

• tardive dyskinesia — like a tick (people often quit this medication because of this)

Schizophrenia Pharmacological Treatments — Second-Generation Antipsychotics

• fewer extrapyramidal symptoms

• side effects include drowsiness and weight gain

Schizophrenia Pharmacological Treatments — Estrogen

• possible role in schizophrenia

  • research shows a spike in schizophrenia during menopause in women (when estrogen levels are low)

    • estrogen may be a protective factor?

Schizophrenia Pharmacological Treatments — The Patient’s Perspective

• not all patients benefit from antipsychotic medications

• may show clinical improvement but still need help

• side effects may lead patients to discontinue taking the medication

• some patients may try to avoid taking medications because, to them, needing to take medications confirms that they are mentally ill

Schizophrenia Treatments — Psychosocial Approaches

• case management

• family therapy

• psychoeducation

• social-skills training

• cognitive remediation

  • takes advantage of neuroplasticity — train self to organize things in a book

• cognitive-behaviour therapy

  • reality test self

  • implement positive experiences in life

• exercise