Characteristics of Schizophrenia
GENERAL CHARACTERISTICS OF SCHIZOPHRENIA
- Schizophrenia is a severe and chronic mental disorder characterised by disturbances in thought, perception, and behaviour.
- People with schizophrenia commonly experience hallucinations (seeing, hearing, or otherwise sensing things that aren’t there), and delusions (strongly held beliefs that aren’t based in reality).
- They may also exhibit disorganised speech or behaviour and decreased participation in daily activities.
SPECIFIC SYMPTOMS AND CLASSIFICATIONS
Positive Symptoms
- Labelled as ‘positive’ because they represent additional behaviours not seen in the general population. These include:
- Hallucinations, the most common being auditory, followed by visual.
- Delusions including paranoid delusions (believing others are plotting against them) and delusions of grandeur (believing they have special powers or are famous).
- Thought disorder, which involves difficulty organising thoughts or connecting them logically. Speech may be garbled or hard to understand.
Negative Symptoms
- These are deficits of normal emotional and behavioural functioning:
- Avolition (or apathy), a lack of initiative or persistence.
- Anhedonia, the inability to experience pleasure.
- Alogia, diminished speech output.
- Flat affect, lack of emotional expression during conversation.
Cognitive Symptoms
- These symptoms often make it hard to lead a normal life and include:
- Disorganised thinking, where the person might have trouble organising their thoughts or connecting them logically.
- Impairments in working memory, problem-solving, and attention.
DIAGNOSIS AND CRITERIA
- The DSM-5 criteria for a diagnosis of schizophrenia includes at least two of the following symptoms for a significant portion of time during a 1-month period: hallucinations, delusions, disorganised speech, disorganised behaviour, and negative symptoms.
- At least one of the symptoms must be one of the first three listed above.
- Additionally, the person must show continuous signs of the disturbance for at least 6 months, with at least 1 month of active symptoms.
EPIDEMIOLOGY AND PROGNOSIS
- Schizophrenia affects about 1% of people worldwide.
- The condition usually begins in late adolescence or early adulthood, with men tending to show symptoms earlier than women.
- The course of the illness is typically chronic, and while some individuals may experience only a single episode, most suffer from recurring episodes of psychosis and may continue to display some level of impaired functioning.
AETIOLOGY
- Experts generally agree that, while the exact cause of schizophrenia remains unknown, it is likely due to a combination of genetic, biochemical, and environmental factors.
- Family, twin, and adoption studies provide evidence for the role of genetics in the transmission of schizophrenia.
- Dysfunction in the dopamine system is believed to play a significant role in the disorder.
- Environmental risk factors may include complications during pregnancy or birth, viral infections, psychosocial factors, and drug use.