How Schizophrenia Works

By: Jane McGrath  | 
Mental Disorder Pictures Schizophrenics experience a disconnect with reality. See more mental disorder pictures.
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History suggests that schizophrenia has probably been plaguing people and throwing them into social isolation for millennia. Despite the vast amounts of research, the complex disorder, characterized by bizarre behavior and emotional withdrawal, remains largely a mystery. As many as 24 million people worldwide and about 1 percent of the American population 18 and up have schizophrenia [source: WHO, NIMH]. If a family member has it, you may wonder, is schizophrenia genetic and therefore do you have higher a schizophrenia risk? About 10 percent of those with the disorder end their own lives [source: NIMH]. Schizophrenics often experience delusions, hallucinations, social and emotional withdrawal and unexplainable behavior.

Although the disorder has probably been present throughout human history, it was not classified accurately until the late 19th century. In the early 20th century, the German psychiatrist Eugen Bleuler came up with the name "schizophrenia," from the Greek words for "split" and "mind," to describe the illness. He chose this term based not on the idea of "split personalities," a common misconception, but rather because schizophrenics experience a disconnect with reality. Bleuler also often referred to the disease in the plural ("schizophrenias") as he recognized that the condition can take an array of different forms.


Sometimes, it is difficult to distinguish schizophrenia from other psychiatric disorders such as depression or bipolar disorder, which is one reason why it's so important to see a doctor who can rule out other possibilities.

Knowing that the disorder can come so late in life can be frightening for young adults who suspect they might already be developing or will develop schizophrenia. So, how do you know if you're experiencing the onset of schizophrenia? Knowing the specific symptoms will help you decide whether you should consult a trained psychiatrist for a diagnosis, and we'll discuss those on the next page.


Schizophrenia Symptoms and Types

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Schizophrenia usually develops in men between their late teens and early twenties, whereas in women, it commonly develops between the mid-twenties and early thirties. Symptoms of schizophrenia may develop gradually (over years), or quickly (over a few weeks). The symptoms are usually classified as positive or negative. However, the purpose of these names isn't to indicate that symptoms are good or bad. Rather, positive symptoms merely refer to those that portray distorted or exaggerated forms of normal activity. For instance, positive symptoms include:

  • Delusions
  • Hallucinations
  • Disorganized speech
  • Purposeless movement activity or lack of activity (known as catatonic behavior)

On the other hand, negative symptoms refer to those that show a lack of normal behaviors. Examples of negative symptoms are:


  • Failing to express or feel emotion
  • Failing to take pleasure in life
  • Having an attitude of general apathy

Some categorize certain negative symptoms as cognitive, or dealing with attention and memory. Cognitive symptoms include:

  • Short attention span
  • Lack of memory skills
  • Inability to plan or organize

Other symptoms include a disruption of work, relationships and personal hygiene. For someone to be diagnosed with schizophrenia according to the widely accepted authority, the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), a certain number of symptoms must show up, and the condition must last for at least six months.

Schizophrenia can take several forms, and these are broken into the following categories:

  • Paranoid: Characterized by delusions and hallucinations. Often, people with paranoid schizophrenia believe they are being victimized by others.
  • Disorganized: Consists of disorganized thinking and behavior that may be incoherent to others and a failure to express emotions.
  • Catatonic: People with catatonic schizophrenia may move around or talk excessively and unexplainably, or may become still and uncommunicative.
  • Undifferentiated: This type of schizophrenia is a catch-all category for someone with a mix of symptoms that don't quite fit in any of the other categories.
  • Residual: If someone has a history of schizophrenia and experiences an extended period of time with negative but no positive symptoms, they can be said to have residual schizophrenia. [source: WebMD]

A few conditions are very similar to schizophrenia. Schizophreniform, for instance, can include positive and negative symptoms of schizophrenia, but only lasts from one to six months. Another similar condition is schizoaffective disorder. Those with schizoaffective disorder suffer from both symptoms of schizophrenia and a mood disorder (such as depression).

Many of the symptoms of schizophrenia can have drastic effects on a patient's life in daily activities, work, social life and relationships. There are a number of common issues that patients face, and options for how to interact with a schizophrenic person.

­Delusions refer to false beliefs, and hallucinations refer to false sensations. Some typical delusions include paranoid beliefs about being victimized by others, or believing oneself to be a famous historical figure (such as Napoleon or Jesus Christ). Hallucinations can come in the form of visions, smells, sounds, feelings or even taste. Most commonly, schizophrenics believe they hear voices. These voices often comment on the person's behavior or give the person orders [source: Cleveland Clinic].


Living with Schizophrenia

After looking at the symptoms, it should come as no surprise that schizophrenics can lead difficult and socially isolated lives. Indeed, given that the disorder usually develops during a time in life when people typically learn essential occupational and self-sufficiency skills, it can be difficult for schizophrenics to reintegrate into society. Most don't get married, raise a family or have gainful employment. Sadly, as many as 5 percent of schizophrenics end up homeless [source: Javitt].

These factors may contribute to the tragically high percentage of schizophrenics who die by suicide (10 percent) [source: NIMH]. However, keep in mind that, as high a rate as that is, this statistic only measures those who complete suicide. The exact statistics for those schizophrenics who attempt suicide are not known but are thought to range between 18 percent and 55 percent [source: Gupta].


Experts disagree over whether schizophrenia makes someone violent. Statistics show that schizophrenia does not usually cause violent behavior, and the majority of those with schizophrenia are not violent. Indeed, schizophrenics are more likely to be victimized by violent crime than to commit it against others [source: Javitt]. In general, those with a history of violence before the onset of the condition may continue violent behavior, and those who had been nonviolent are unlikely to become violent.

However, other studies do indicate that schizophrenics are more likely than the general population to be violent if they also abuse drugs and alcohol. When schizophrenic people do become violent toward others, it is usually against friends or family and in the home [source: NIMH]. Notably, the most likely victim of their violence, of course, is themselves, as shown by the high suicide rates.

The National Institute of Mental Health (NIMH) offers some advice for those who want to help people who have schizophrenia. You can work to generate a positive and supportive atmosphere to help schizophrenics make improvements and learn to function. Because people suffering from schizophrenia often struggle to set goals, others can help guide them through it. By setting small, attainable goals, you can help them slowly and steadily grow more independent.

For friends and family of schizophrenics, responding to delusions and hallucinations can become difficult. For this situation, NIMH recommends neither trying to dispute nor play along with the schizophrenic's false notions. Instead, politely convey that people are entitled to their own opinions, but that you disagree.Schizophrenia often comes about so suddenly that it is difficult to grasp why it's happening. Despite the wealth of studies and research on the disorder, little is known about the cause. Next, we'll talk about some theories.


Causes of Schizophrenia

Scientists don't know what causes schizophrenia, but most likely it develops out of both environmental and genetic factors. Relatives of people with schizophrenia are more likely to develop it. For instance, you have a 10 percent chance of developing the disorder if you have a first degree relative (such as a parent or sibling) with schizophrenia (as opposed to a 1 percent chance in the general population) [source: NIMH]. In addition, in identical twins, if one is schizophrenic, the other has a 40 percent to 65 percent chance of developing it [source: NIMH]. Although statistics indicate that genetics certainly have something to do with it, they do not tell the whole story. Merely looking at genetic makeup cannot help scientists definitively determine who will develop the disorder. It is possible that several different genes play various parts in schizophrenia, and other factors contribute as well.

If you are genetically predisposed to the disorder, environmental factors could contribute to your chances of developing it. Some of these factors go back even before birth. For example, one study suggests that if a mother gets sick with the flu during pregnancy, this can increase the risk of the child developing schizophrenia [source: Minkel]. In addition, complications during birth, malnutrition and brain injuries also might increase someone's chances of getting it.


Some studies reveal possible causes for the specific symptoms of schizophrenia. For instance, the hallucinations that many schizophrenics experience might stem from the individual's disconnect from reality. If their ideas are split off from their actual sensations or feelings, they might not be able to predict their own behavior [source: Zimmer]. In this way, if they fail to predict their own inner voice, they might come to the conclusion that it did not come from themselves. In addition, this could explain why many believe someone else is controlling their behavior.

Scientists also look for answers by studying the chemical makeup of the brain for people with schizophrenia. The medications that treat schizophrenia offer just as many questions as answers about how human brain functions play a part in the disorder. Based on the effects of different drugs, researchers now believe the neurotransmitters - chemicals that act as messengers between brain cells - dopamine and glutamate play major roles in schizophrenia. Next, in the treatments section, we'll discuss how helpful medications affect these neurotransmitters.


Schizophrenia Treatment

Medications called antipsychotics are available for people with schizophrenia. Unfortunately these are not always entirely effective, and most schizophrenics live with at least some symptoms. As many as 14 percent of those schizophrenics who take antipsychotics show no significant improvement [source: Javitt].

Antipsychotic drugs affect the amount of dopamine, a neurotransmitter, in your brain by blocking dopamine receptors. When their effectiveness in fighting schizophrenia was first discovered in the 1950s, scientists came to the conclusion that an improper balance of dopamine in the brain led to schizophrenia. However, with the 1980s came the development of new atypical antipsychotics that inhibited dopamine receptors less and that of other neurotransmitters more. When these proved effective in fighting more symptoms and causing fewer side effects, it prompted a reexamination of other neurotransmitters' role in schizophrenia.


Although older versions of antipsychotics are only effective in fighting positive symptoms of the disorder, atypical antipsychotics treat negative symptoms as well. Finding the appropriate medicine and dosage for each patient can be a difficult process, as side effects vary depending on the individual.

Some of the possible side effects with antipsychotic medications are weight gain, restlessness, stiff muscles, drowsiness and muscle spasms. Although lowering the dosage or finding a different antipsychotic may help get rid of these symptoms, many people stop taking the medication because of the side effects.

In addition to medications, other treatments for schizophrenia can help, such as community support activities and psychotherapy. Community support activities can include training schizophrenic people in particular skills to help them become contributing members of society. Psychotherapy can add structure and confidence to the patient's life, increasing their ability to perform daily activities and chores on their own. Group therapy and family therapy have been shown to help as well [source: Grohol].

Despite falling out of favor in the mid-20th century, electroconvulsive therapy (ECT) (also known as shock therapy) is still practiced for such disorders as schizophrenia and severe depression. About 100,000 Americans receive ECT every year [source: Mayo Clinic]. Though the process has changed dramatically since its first inception in the 1930s, it remains controversial. In ECT, electric currents sent to your brain cause seizures and change chemical activity. Though no one is sure how exactly it works, after recurring treatments, it may improve schizophrenic symptoms.


Frequently Answered Questions

What are the 5 symptoms of schizophrenia?
The five symptoms of schizophrenia are hallucinations, delusions, disorganized speech, disorganized behavior, and negative symptoms.

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