Schizophrenia is a serious and challenging medical illness that affects well over 2 million American adults. Although it is often feared and misunderstood, schizophrenia is a treatable medical condition.

Schizophrenia often interferes with a person's ability to think clearly, to distinguish reality from fantasy, to manage emotions, make decisions, and relate to others.

People with schizophrenia may hear voices other people don't hear or they may believe that others are reading their minds, controlling their thoughts, or plotting to harm them. These experiences are terrifying and can cause fearfulness, withdrawal, or extreme agitation. People with schizophrenia may not make sense when they talk, may sit for hours without moving or talking much, or may seem perfectly fine until they talk about what they are really thinking. Because many people with schizophrenia have difficulty holding a job or caring for themselves, the burden on their families and society is significant as well.

Symptoms usually develop in men in their late teens or early twenties and women in the twenties and thirties, but in rare cases, can appear in childhood. They can include hallucinations, delusions, disordered thinking, movement disorders, flat affect, social withdrawal, and cognitive deficits.

The symptoms of schizophrenia fall into three broad categories:

• Positive symptoms are unusual thoughts or perceptions, including hallucinations, delusions, thought disorder, and disorders of movement.
• Negative symptoms represent a loss or a decrease in the ability to initiate plans, speak, express emotion, or find pleasure in everyday life. These symptoms are harder to recognize as part of the disorder and can be mistaken for laziness or depression.
• Cognitive symptoms (or cognitive deficits) are problems with attention, certain types of memory, and the executive functions that allow us to plan and organize. Cognitive deficits can also be difficult to recognize as part of the disorder but are the most disabling in terms of leading a normal life.

The first signs of schizophrenia typically emerge in the teenage years or early twenties, often later for females. Most people with schizophrenia contend with the illness chronically or episodically throughout their lives, and are often stigmatized by lack of public understanding about the disease. Schizophrenia is not caused by bad parenting or personal weakness. A person with schizophrenia does not have a "split personality," and almost all people with schizophrenia are not dangerous or violent towards others while they are receiving treatment. The World Health Organization has identified schizophrenia as one of the ten most debilitating diseases affecting human beings.