Seminar 9- schizophrenia and biopsychosocial approach

How does schizophrenia impact the brain?

• Suppression of default mode network absent

• Weaker connections between brain areas

• Hallucinations due to dysfunction of areas

What is the default mode network?

• Internal/‘inner eye’

• Responsible for daydreaming and mind-wandering

What are some issues with neurotransmitters to explain schizophrenia?

• Activity of dopamine neurons

• Dopamine imbalance hypothesis

• Glutamate linked to psychotic-like symptoms

What is dopamine responsible for?

• Reward and reinforcement (feelings of euphoria)

• Motor movements

Where is dopamine produced?

In the brainstem

Where else in the brain does dopamine affect?

Has projections which affect activation in the cortex (surface of the brain)

What are positive behaviours?

• Added behaviours

• e.g hallucinations

What are negative behaviours?

• Behaviours which are taken away

• e.g motor function

How does dopamine affect the midbrain regions?

Overactivity → positive symptoms

How does dopamine affect cortical regions?

Under-activity → negative symptoms

Is dopamine excitatory or inhibitory?

Excitatory

What is the dopamine imbalance hypothesis?

• Overactivity in the midbrain/brainstem results in positive symptoms

• Like hallucinations/delusions

• Under-activity in the cortex results in negative symptoms

• Like lack of motivation/flat affect

What does changes in dopamine activity result in?

• Inability to stop influx of thoughts

• Increased information flow resulting in more creative thinking

What was the first antipsychotic discovered?

Chlorpromazine (thorazine)

What type of drug was chlorpromazine:

a) Typical

b) A-typical

a) Typical

What is a ‘typical’ antipsychotic?

• First generation antipsychotic drug

• Only affect positive symptoms

When was chlorpromazine discovered?

1954

What were the effects of chlorpromazine?

• Reduces dopamine activity in the brain

• Reduces agitation, hostility, aggression, hallucinations, delusions

How did chlorpromazine impact hospitalisation?

Increases time between hospitalisations

What type of symptoms does chlorpromazine NOT change?

• Negative symptoms

• Cognitive deficits

Why does chlorpromazine not change negative symptoms?

• Negative symptoms are due to under-activity of dopamine

• Early drugs only target overactivity of dopamine

What are some side effects of chlorpromazine?

• Tardive dyskinesia

• Weight gain

What is Tardive dyskinesia?

• Movement disorder

• Involuntary movement of lower face, limbs

• Dopamine is used for motor movements

When were atypical drugs introduced?

Around 1990

What is an ‘atypical’ antipsychotic?

Second generations antipsychotic

How do typical and atypical antipsychotics differ?

• Atypical targets specific dopamine receptors, not all types of dopamine

• Atypical produces less tardive dyskinesia

• Atypical are equal or sometimes more effect than typical

What are the advantages of atypical drugs compared to typical drugs?

• Less likely to cause movement-related dopamine side effects

• More effective in treating negative symptoms

• Target the dopamine imbalance, rather than just overactivity

What are the disadvantages of atypical drugs compared to typical drugs?

• Side effects such as weight gain, diabetes, cardiac problems

• No greater improvements than with older antipsychotics

What are some limitations of all antipsychotic medications?

• They do not cure schizophrenia

• Unwanted side effects

• ‘Revolving door’ pattern of hospitalisation, discharge, and rehospitalisation

How does nicotine affect the brain?

• Mimics acetylcholine in the brain (excitatory)

• Improves negative symptoms

• Stimulates under active parts of the cortex

What percentage of schizophrenia patients smoke?

80%

What are the environmental origins of schizophrenia?

• Direct brain damage/injury during early development

• Prenatal complications (stress, immune responses, starvation during pregnancy)

How do family interventions reduce relapse and hospitalisations?

• Provide practical emotional support to family members

• Provide information about support services

• Help the family develop model of schizophrenia

• Modify unhelpful, inaccurate beliefs about schizophrenia

• Enhance positive communications

• Involve everyone in relapse prevention plan

• Provides ‘psychological healthy’ environment

Do social factors affect schizophrenia?

• Those with biological mothers with schizophrenia and those with no genetic history of schizophrenia

• Significantly more likely to show signs of serious mental disorder

• If they were raised in a ‘psychologically disturbed’ family environment

• Compared to those raised in a ‘psychologically healthy’ environment

What is one psychosocial intervention for schizophrenia?

Cognitive behavioural therapy (CBT)

Describe how CBT is used to treat schizophrenia

• Importance of individual’s interpretation of psychotic events

• Understand individual’s interpretation of past and present events

• Normalise and reduce impact of symptoms

What does ‘early intervention’ mean?

• Seek out high-risk individuals

• Develop cognitive skills to increase attention, memory, executive control, and other cognitive processes

What is the biopsychosocial model?

Interactions between genetics (biology), personality (psychology), and environment (social) and their impact on mental health

Who proposed the biopsychosocial model?

George Engel

What did Engel suggest?

Mental health should be understood from more than just a biological perspective