Psychology: Schizophrenia Definition and Symptoms

Study Notes

Schizophrenia is a chronic and severe mental disorder characterized by disturbances in thought, perception, and emotion.
It affects approximately 1% of the global population, with a lifetime prevalence of 0.3-0.7%.

Positive symptoms:
- Hallucinations (auditory, visual, or tactile)
- Delusions (fixed, false beliefs)
- Disorganized thinking and speech
- Abnormal motor behavior
Negative symptoms:
- Affective flattening (reduced emotional expression)
- Alogia (poverty of speech)
- Avolition (lack of motivation)
- Anhedonia (pleasurelessness)
Cognitive symptoms:
- Impaired attention and memory
- Difficulty with executive function and processing speed

Genetic factors:
- Family history increases risk
- Genetic mutations (e.g., 22q11 deletion syndrome)
Environmental factors:
- Prenatal and perinatal complications
- Viral infections
- Social and economic stress
- Substance abuse
Neurobiological factors:
- Imbalances in dopamine and glutamate neurotransmitters
- Abnormalities in brain structure and function (e.g., ventricular enlargement)

Diagnosis:
- Clinical evaluation of symptoms and behavior
- Exclusion of other medical conditions
- Use of diagnostic criteria (e.g., DSM-5)
Treatment:
- Antipsychotic medications (e.g., dopamine receptor antagonists)
- Psychosocial interventions (e.g., cognitive-behavioral therapy, family therapy)
- Rehabilitation and social support

Outcome:
- Variable, with some individuals experiencing full recovery and others experiencing persistent symptoms
- Factors influencing outcome include prompt treatment, social support, and cognitive function
Prognosis:
- Poorer prognosis associated with:
  - Early onset
  - Presence of negative symptoms
  - Lack of social support
- Better prognosis associated with:
  - Late onset
  - Presence of positive symptoms
  - Good social support

Schizophrenia is a chronic and severe mental disorder characterized by disturbances in thought, perception, and emotion.
It affects approximately 1% of the global population, with a lifetime prevalence of 0.3-0.7%.

Positive symptoms of schizophrenia include hallucinations, delusions, disorganized thinking and speech, and abnormal motor behavior.
Hallucinations can be auditory, visual, or tactile.
Negative symptoms of schizophrenia include affective flattening, alogia, avolition, and anhedonia.
Cognitive symptoms include impaired attention and memory, and difficulty with executive function and processing speed.

Genetic factors contribute to the risk of schizophrenia, with a family history increasing the risk.
Genetic mutations, such as 22q11 deletion syndrome, can also contribute to the risk.
Environmental factors, such as prenatal and perinatal complications, viral infections, social and economic stress, and substance abuse, can contribute to the risk of schizophrenia.
Neurobiological factors, including imbalances in dopamine and glutamate neurotransmitters, and abnormalities in brain structure and function, can contribute to the risk of schizophrenia.

Diagnosis of schizophrenia involves a clinical evaluation of symptoms and behavior, excluding other medical conditions, and using diagnostic criteria such as the DSM-5.
Treatment of schizophrenia typically involves antipsychotic medications, such as dopamine receptor antagonists, and psychosocial interventions, such as cognitive-behavioral therapy and family therapy.
Rehabilitation and social support are also important components of treatment.

The outcome of schizophrenia varies, with some individuals experiencing full recovery and others experiencing persistent symptoms.
Factors influencing outcome include prompt treatment, social support, and cognitive function.
A poorer prognosis is associated with early onset, presence of negative symptoms, and lack of social support.
A better prognosis is associated with late onset, presence of positive symptoms, and good social support.