Symptoms:

Research indicates that symptoms in childhood strongly predict disease in adulthood. In one long-term study, over 40% of people with schizophrenia who developed the disease in young adulthood had reported psychotic symptoms by age 11. For children with a family history of schizophrenia, the following inherited traits may be warning signs:

• Deficits in working (short-term) and verbal memory
• Impairments in gross motor skills (the child's ability to control different parts of the body)
• Attention deficits
• A decline in verbal memory, IQ, and other mental functions

Any signs of hallucinations or delusions must be differentiated from normal childhood fantasies.

Most often, early warning signs go unnoticed, and schizophrenia usually becomes evident for the first time in late adolescence or early adulthood. Schizophrenia that starts in childhood or adolescence tends to be severe. It should be strongly noted that the traits discussed above, even combinations of them, can be present without schizophrenia.

Negative Symptoms

A person with schizophrenia may have the following negative symptoms:

• Lack of self confidence
• Lack of emotions
• Colorless speaking tones
• Inappropriate reactions to events (such as laughing hysterically over a loss)
• A general loss of interest in life and the ability to experience pleasure

Lack of responsiveness and poor sociability often appear in childhood as the first indications of schizophrenia. Certain imaging techniques suggest that these findings are based on biologic changes in specific parts of the brain. In many patients, however, negative symptoms do not appear until after positive symptoms develop. Negative symptoms tend to be more common than positive symptoms in older patients and typically persist after positive symptoms have been treated.

Psychotic Symptoms

Psychotic symptoms, particularly delusions and hallucinations, are the most widely recognized manifestations of schizophrenia.

• Hallucinations. A hallucination is the experience of seeing, hearing, tasting, smelling, or feeling something that doesn't really exist. Auditory hallucinations are false senses of sound such as hearing voices that go unheard by others. They are the most common psychotic symptoms, affecting about 70% of patients.
• Delusions. A delusion is a fixed, false belief. It can be bizarre (such as invisible aliens have entered the room through an electric socket) or nonbizarre (such as unwarranted jealousy or the paranoid belief in being persecuted or watched).

Psychotic symptoms usually occur every now and then, alternating with periods of remission. They typically occur in men ages 17 - 30 and in women ages 20 - 40.

Cognitive Impairment (Disordered Thinking)

The symptoms of cognitive impairment and disordered thinking may occur before other symptoms of schizophrenia. They include:

• A lack of attention.
• Impaired information processing and an aberrant association between words and ideas. Sometimes this condition is so extreme that speech becomes incoherent and is referred to as "word salad." Patients may connect words because of similarity of sound, rather than by meaning, a condition known as "clang associations."
• Memory impairment. In keeping with other aspects of disordered thinking, memory impairment in schizophrenia is likely to involve the inability to connect an event with its source into a complete and whole memory. For instance, a patient may recall and even feel a familiarity with a specific event but be unable to remember where, when, or how it took place.
• Backward masking dysfunction. This is a trait in which a distraction causes a person to forget a preceding event. It might be an important symptom and a marker of schizophrenia even in people with normal working memories.

People with schizophrenia do poorly on mental tasks requiring conscious awareness, such as verbal fluency, short-term and working memory, and processing speed. However, they are no worse than the general population in underlying (implicit) learning, such as grammar skills, vocabulary, and spatial skills (such as map reading). Some experts believe that impaired verbal memory in schizophrenia is a consequence of depression and slowness, but not a result of the disease process.

Other Symptoms

People with schizophrenia may experience other symptoms, such as intolerance of heat (often associated with antipsychotic medications) and a reduced sense of smell.

Symptoms of Progression to Full-Blown Schizophrenia

The course of the disease varies from one patient to the next. Symptoms of psychosis can become gradually or suddenly evident.

• In up to a third of patients, the disease is unrelenting and progresses from the first episode onward.
• In others, schizophrenia follows a fluctuating course with psychotic flare-ups, followed by remissions.
• In one study, a third of patients experienced a complete remission of symptoms within 3 years after one or more episodes. Women are more likely to go into remission, possibly because of some protective effect of estrogen on the brain.

Typically, patients develop considerable cognitive dysfunction (disordered thinking) within the first 4 - 5 years of the onset of psychotic symptoms. Some evidence indicates that the physical disease process in schizophrenia is progressive, as with Alzheimer's and Parkinson's disease. However, schizophrenia does not progress in the same way as those two diseases. Unlike Parkinson's and Alzheimer's, cognitive function usually eventually stabilizes. Psychosis, disorganized thought, and negative symptoms often improve over time, although, even in such cases, deficits in verbal memory usually persist. (Thought disorder often improves along with improvements in negative symptoms.)