Biological Treatments for Schizophrenia & Clinical Depression (OCR GCSE Psychology): Revision Note

The use of anti-psychotics to treat schizophrenia

• Treatments for schizophrenia aim to reduce psychotic symptoms and improve overall mental functioning.

• One of the main biological treatments is the use of antipsychotic medication, which works by changing brain activity and communication between neurons and synapses

How anti-psychotics work

• Antipsychotics alter the balance of neurotransmitters, particularly dopamine, in the brain

• In schizophrenia, overactivity of dopamine in certain brain regions is believed to cause positive symptoms such as hallucinations, delusions, and disorganised thinking

• These drugs block dopamine D2 receptors on the postsynaptic neuron, reducing dopamine transmission

  • This calms overactive neural activity, leading to clearer thinking and fewer psychotic symptoms

• By normalising dopamine function, antipsychotics help restore communication between brain cells, supporting improved mental health

Types of anti-psychotics

Conventional (typical) antipsychotics

• Conventional antipsychotics were first introduced in the 1950s

  • Examples include Chlorpromazine and Haloperidol

• They work by strongly blocking dopamine receptors, reducing positive symptoms

• However, side effects can include:

  • tardive dyskinesia (involuntary facial or body movements)

  • muscle stiffness and tremors

  • sedation or tiredness

• While effective for many, typical antipsychotics can sometimes worsen negative symptoms (like apathy or withdrawal)

Atypical (second-generation) antipsychotics

• Atypical antipsychotics were first introduced in the 1990s

  • Examples include Clozapine, Risperidone, and Olanzapine

• These drugs block dopamine receptors less strongly and also act on serotonin receptors

• This broader action helps to:

  • reduce both positive and negative symptoms

  • Lower the risk of movement-related side effects seen in typical drugs

• However, they can still cause side effects such as rapid weight gain or metabolic problems

How they improve mental health

• By reducing dopamine transmission, antipsychotics:

  • lessen hallucinations and delusions, helping patients distinguish reality from psychosis

  • allow clearer thinking and better concentration

  • improve social functioning and the ability to engagement in daily life and therapy

• Overall, they stabilise mood, reduce distress, and improve quality of life

• For many, combining medication with psychological treatments (e.g. CBT) leads to the best long-term outcomes

The use of antidepressants to treat clinical depression

• Clinical depression is linked to chemical imbalances in the brain, particularly involving the neurotransmitters serotonin and noradrenaline

• Antidepressants work by increasing the levels of these neurotransmitters, which help regulate mood and restore normal brain function

Selective serotonin reuptake inhibitors (SSRIs)

• SSRIs are a common group of antidepressants, including Fluoxetine (Prozac) or Sertraline

• SSRIs prevent serotonin from being reabsorbed into the pre-synaptic neuron, causing a build-up in the synaptic gap

• This allows serotonin to remain active for longer, improving communication between neurons

How antidepressants improve mental health

• The improved neurotransmission helps stabilise mood and reduce depressive symptoms

• By restoring the brain’s chemical balance, antidepressants can relieve symptoms such as:

  • persistent low mood and sadness

  • anxiety, irritability, and fatigue

  • poor concentration and sleep problems

• Enhanced neurotransmitter function helps the brain regain normal activity, allowing people to think more clearly and participate in daily life

• Antidepressants can also make people more responsive to psychotherapy, as improved mood and energy help them engage more effectively in treatment

• However they can cause side effects such as

  • nausea,

  • headaches

  • weight changes

  • reduced libido