Schizophrenia Overview

schizophrenic brain

Schizophrenia is one of the most devastating and debilitating forms of mental illness. Classified as a psychotic disorder, it afflicts approximately 1% of the world’s adult population. Historical documents suggest that schizophrenia has plagued mankind for thousands of years.

This disorder was given its name by Swiss psychiatrist Eugen Bleuler in the early 1900s. Literally translated, the word "schizophrenia" is Greek for "split mind". Because of this, many people mistakenly believe it refers to someone with multiple personalities. Bleuler’s intent, however, was to depict the schizophrenic individual’s "split" from reality and the disordered or "broken" thought processes that characterize this disorder.

For a description of a mental illness in which a person has multiple personalities, see Dissociative Disorders.

Symptoms of Schizophrenia

Schizophrenia usually develops in the early to mid-20s in males, and the late twenties in females. However, it can develop at any stage in life including mid-life, adolescence and even early childhood.

With schizophrenia, individuals may exhibit a variety of symptoms. They are categorized as either "positive" or "negative".

Positive symptoms of schizophrenia

Positive symptoms involve normal functions (e.g. language, perception) that are very distorted or exaggerated. They include:

Firmly held (and often bizarre) beliefs that are not based in reality, such as believing that aliens have removed one’s organs
E.g. hearing voices or seeing things that aren’t really there
Disorganized thinking or speech
E.g. gibberish ("word salad") or constantly jumping from one topic to next
Severely disorganized or catatonic behavior
E.g. the inability to perform daily tasks, wearing multiple layers of clothes on a hot day, or complete unresponsiveness to one’s surroundings

Negative symptoms of schizophrenia

Negative symptoms, on the other hand, refer to a significant decrease or complete loss in areas of normal functioning. They may include:
Significant or complete lack of emotional expressiveness
Also known as "flattening of affect"
Poverty of speech
E.g. very brief or empty responses
Inability to begin or perform goal-directed activities

Social impact of schizophrenia

Schizophrenia symptoms often negatively impacts many, if not all, aspects of a person’s life – their thoughts, actions, perceptions, social interactions, and ability to do normal day to day tasks. It is not uncommon for individuals with schizophrenia to become socially withdrawn, paranoid, erratic, or extremely agitated, especially when their symptoms are untreated or if they discontinue their current treatment.

Types of Schizophrenia

Since the symptoms of schizophrenia can vary significantly from one case to the next, there are currently five different subtypes. Each schizophrenia subtype is based on the predominant symptoms.

Paranoid Schizophrenia
One of the most common subtypes, the most prominent symptoms of paranoid schizophrenia are delusions and / or frequent auditory hallucinations (usually voices). Impairment in thinking, speech, behavioral organization, and emotional expressiveness, however, is not significant.
Disorganized Schizophrenia
Historically known as "hebephrenic schizophrenia", the prominent symptoms of this subtype are disorganized speech and behavior, lack of emotional expression, and difficulties performing daily activities.
Catatonic Schizophrenia
This is the rarest subtype of schizophrenia. The predominant symptoms involve some form of psychomotor disturbance. Examples include a significant or complete lack of responsiveness to one’s surroundings, maintaining a rigid or bizarre posture, excessive movement that has no purpose, or mindlessly repeating another person’s words or movements.
Residual Schizophrenia
This subtype is diagnosed when the person has had at least one schizophrenic episode. However, there are currently no prominent positive symptoms but there is still evidence of the disorder (e.g. strange beliefs or behaviors, or speech that is still a little disorganized).
Undifferentiated Schizophrenia
This subtype is diagnosed when clear symptoms of schizophrenia are present, but they don’t meet the criteria for one of the other four subtypes.

Causes of Schizophrenia

Research has not yet provided a definitive cause for schizophrenia. While the disease is believed to be primarily biologically based, several factors are believed to play a role in the development of the disorder.

Contributing factors likely include:

Many studies have shown that schizophrenia has a significant genetic component. For example, children with a schizophrenic biological parent or other immediate family member have a fairly high risk of developing the disorder. The risk is greatest if both biological parents have schizophrenia.
Brain abnormalities
Individuals with schizophrenia have structural differences in their brains compared to individuals without the disorder.
Brain chemistry
An imbalance in certain brain chemicals, such as dopamine, is believed to play a role in the development of schizophrenia. These chemicals play a role in how a person responds to or perceives external stimuli such as sounds and smells.
Environmental stressors and trauma, which may include exposure to certain toxic substances, may trigger the development of schizophrenia in those who are predisposed to the disorder.

Diagnosing Schizophrenia

Schizophrenia is diagnosed by a qualified mental health or medical professional. In many cases, a family member or close friend notices the unusual or bizarre symptoms and initiates an evaluation. Lab tests, drug screening, and / or x-rays are often part of the diagnostic process to first rule out other potential causes for the unusual symptoms.

While lab tests can rule out other possible conditions, there are currently no medical tests to diagnose schizophrenia. The psychiatric assessment includes interviewing and observing the patient, as well as obtaining additional information from family members, others who know the patient, and /or past treatment providers and psychiatric records if available.

Signs of the disorder must be present for at least 6 months in order to be diagnosed with schizophrenia. If symptoms typical of schizophrenia have been present for less than 6 months, the most likely diagnoses are schizophreniform disorder or brief psychotic disorder.

Treatment of Schizophrenia

As mentioned previously, there is currently no known cure for schizophrenia. However, appropriate treatment can help reduce and alleviate symptoms in most cases. Although each person responds to treatment differently, some individuals with this disorder are able to live productive lives if they stick with their prescribed treatment regimen.

Treatment often involves a combination of medication and psychosocial treatments. Many schizophrenic patients also require hospitalization if they are highly symptomatic. Hospitalization allows the patient to be stabilized in a safe, secure environment under close medical supervision.

Antipsychotic drugs are the most commonly prescribed medications for schizophrenia. Popular antipsychotics include Risperdal, Zyprexa, Clozaril, and Abilify, to name a few.
Antipsychotic medication can be very effective in terms of reducing or alleviating psychotic symptoms and preventing future psychotic episodes for many people with this disorder. However, they sometimes cause troubling side effects that are difficult for some patients to tolerate.
Psychosocial Treatments
Individuals with schizophrenia often struggle in one or more of the following areas: communication, relationships, motivation, daily activities, managing their illness, and vocational issues.
Psychosocial treatments – which may include individual, group, or family therapy; vocational training and rehabilitation, education, and support or self-help groups – can help with each of these areas.

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