The most common symptoms of schizophrenia include changes in the way a person thinks, feels, and relates to other people and the outside environment. No single symptom or specific set of symptoms is characteristic of all schizophrenic patients. Schizophrenia is a devastating disorder for both the patients and their families.Among mental disorders, it is the second leading cause of disease burden.

Onset of schizophrenia typically occurs during adolescence or early adulthood. The period of risk for the development of a first episode is considered to be between the ages of 15 and 35. The problems of most patients can be divided into three phases of variable and unpredictable duration: prodromal, active, and residual.

Positive Symptoms

Positive symptoms are also called psychotic symptoms. Hallucinations are one example. These are perceptual disturbances in any of the senses and are consistent over time.  Delusional beliefs are another example of a positive symptom. These are idiosyncratic beliefs that are rigidly held in spite of their preposterous nature.

Negative Symptoms

Negative symptoms include lack of initiative, social withdrawal, deficits in emotional responding. Affective and emotional disturbances are also seen. Blunted affect or affective flattening is also a negative symptom. Anhedonia is the inability to experience pleasure. Apathy, avolition (lack of will), and alogia (impoverished thinking, poverty of speech) are all negative symptoms. Due to these negative symptoms, many people with schizophrenia become socially withdrawn. This is not only because of the symptoms themselves. The withdrawing is also a result of the manner in which schizophrenics cope with their mental illness.

Image via Wikipedia


Thinking disturbances are examples of disorganization. These involve disorganized speech where a person is able to talk but what they say does not make sense. They often respond to questions in peculiar ways. Responses are often irrelevant and the ideas are disconnected. They often shift topics abruptly. This is referred to as loose association or derailment. Sometimes they show perserveration where they repeat the same word or phrase over and over and over again.

Bizarre Behavior

Catatonia  is immobility and marked muscular rigidity; excitement and overactivity. It is also associated with a stuporous state or reduced responsiveness.
Inappropriate affect is another bizarre behavior. A person displays  incongruity and lack of adaptability in emotional expression.


Schizophrenia is a heterogeneous disorder with many different clinical manifestations and levels of severity.

Catatonic Type
Disorganized Type
Paranoid Type
Undifferentiated Type
Residual Type

Related Psychotic Disorders

Schizoaffective Disorder is when the symptoms of patients fall on the boundary between schizophrenia and mood disorders. Delusional Disorder is when the symptoms do not meet the full symptomatic criteria for schizophrenia, preoccupation for at least one month with delusions that are not bizarre. Brief Psychotic Disorder  is when someone exhibit psychotic symptoms one day to one month.

Gender Differences

Current evidence suggests that men are 30 to 40% more likely to develop schizophrenia than women. It is widely recognized that there are differences between male and female onset, symptoms, and course of the disorder.

Two hypotheses:

Schizophrenia is a single disorder and is expressed differently in men and women.


There are two qualitatively distinct subtypes of schizophrenia: differences in onset.


Twin studies have shown that the average concordance rate for mono-zygotic twins is 48%, whereas the comparable figure for di-zygotic twins is 17%. These findings suggest a strong genetic factors. There is also compelling evidence for the importance of environment.

Leonard Heston’s longitudinal adoption study (1966) indicate genetic factors play role in development of the disorder. There was a link between the disorder with pregnancy and birth complications. People with schizophrenia are more likely than the general population to have been exposed to various problems during their mother’s pregnancy and to have suffered birth injuries.

Dietary factors and viral infections also play a role in the development of schizophrenia. People who develop schizophrenia are somewhat more likely than other people to have been born during the winter when viral infections are more prominent.

Dopamine hypothesis

The dopamine hypothesis Focuses on the function of specific dopamine pathways in the limbic area of the brain. The hypothesis grew out of attempts to understand how antipsychotic drugs improve the adjustment of schizophrenic patients.

In the brain, there are multiple interaction between multiple neurotransmitters, and current research focuses on a broad array of neurotransmitters: serotonin pathways, GABA and glutamate.

Image via Wikipedia – Age standardised disability -adjusted life  year rates from schizophrenia by country

Social Factors Social Class

The evidence supporting an inverse relationship between social class and schizophrenia is substantial. Social causation simply means harmful events associated with membership in the lowest social classes play a causal role in the development of the disorder.

Migrant studies have shown that schizophrenia is higher among people who have migrated to a new country. One possible explanation for this phenomenon is that social adversity increases risk for schizophrenia.

Psychological Causes

Expressed Emotion

The family environment does have a significant impact on the course (as opposed to the etiology) of schizophrenia. In a study, patients who relapsed seemed to react negatively to some feature of their close relationship with their wives or mothers.


Antipsychotic Medication

Antipsychotic medications work mainly to reduce psychotic symptoms. It usually takes two to three weeks before improvement is seen. Positive symptoms respond better to medication than negative symptoms. However, a substantial minority of patients, perhaps 25% do not improve on classical antipsychotic drugs.

Motor Side Effects

Extrapyramidal symptoms (EPS) are muscular rigidity, tremors, restless agitation, peculiar involuntary postures, and motor inertia. EPS may diminish spontaneously after three or four months of continuous treatment. Tardive dyskinesia  is a syndrome that consists of abnormal involuntary movements of the mouth and face, such as tongue protrusion, chewing, and lip puckering, as well as spasmodic movements of the limbs and trunk of the body.

Second-Generation Antipsychotics

Second generation antipsychotics are considered atypical antipsychotics. They are less likely to produce motor side effects and are as effective for treatment of positive symptoms. However, their effect on negative symptoms is about the same as traditional antipsychotics.

Psychosocial Treatment

Family-Oriented aftercare attempts to improve the coping skills of family members through educating them about the disorder. The goal is  improving communication and problem-solving of the family members.

Social skills training is a structured, educational approach that involves modeling, role-playing, and social reinforcement.

There are a few specialized cognitive treatments. Cognitive enhancement therapy (CET) is designed for patients who have recovered from active symptoms, but continue to exhibit cognitive disability. Another option is Assertive Community Treatment which is delivered by an interdisciplinary team.

Related articles

One thought on “Schizophrenia”

Leave a Reply

Your email address will not be published. Required fields are marked *