SCHIZOPHRENIA AND BRAIN FUNCTION

Schizophrenia and Brain Function



Schizophrenia and Brain Function

Introduction

Schizophrenia is the diagnostic category given to patients who experience symptoms of psychosis, such as delusions and hallucinations as well as bizarre behaviour, strange movements, disorganized thinking and speech, decreased emotional expressiveness, and social withdrawal. Many people with schizophrenia do not recognise that their mental functioning is disturbed. Some of its sufferers spend most of their lives haunted with hallucinations. They suffer from paranoia, a feeling of persecution and blunted emotional responses. Investigators are trying to understand schizophrenia as a kind of brain disease but often patients are unresponsive to all kinds of interventions including modern drug treatments. This essay will discuss the biological bases behind schizophrenia in order to understand better why some people suffer from this devastating mental illness.

Analysis

Usually only some of the symptoms mentioned occur in any one person. The term schizophrenia comes from Greek words meaning, "Split mind." However, schizophrenia does not refer to a person with a split personality or multiple personality. Schizophrenia is considered above most other mental illnesses to have the most debilitating effect on the lives of its sufferers. Schizophrenia seriously impairs a person's ability to work, enjoy relationships with others, or take care of them. The disease is characterised by its negative symptoms including emotional withdrawal and impoverished thought and positive symptoms such as the hallucinations and delusions. Symptoms and functioning in people with schizophrenia tend to vary over time, sometimes worsening and other times improving. For many patients the symptoms gradually become less severe as they grow older (Murray et al, 1992).

It is believed that faulty metabolic processes in the brain lead to an excess of these neurochemicals. Cellular observations have also focused on the basal ganglia because schizophrenics often show unusual body postures and mannerisms. Neurochemical studies of these structures show an increase in dopamine D2 receptors in the caudate nucleus and putamen of some patients. The genetic factor in schizophrenia has been emphasised by recent findings that first-degree biological relatives of schizophrenics are 10 times more likely to develop the disorder than members of the general population. Schizophrenia inheritance does not involve a singular dominant or recessive gene however (Mirsky & Duncan, 1986). The emergence of schizophrenia appears to come from multiple genes. Another hypothesis suggests that schizophrenia may be caused by a virus that attacks the hippocampus, a part of the brain that processes sense perceptions. Damage to the hippocampus would account for schizophrenic patients' vulnerability to sensory overload (Van Horn & McManus, 1992).

Twin studies have been a valuable tool in researching this disease. Studies of discordant twins have shown that generally the twin with the disorder has a lower birth weight and may have experienced a traumatic childhood development if different families adopted the twins. These twin studies have also shown that more than 75% had a smaller hippocampus and amygdala (Torrey et al., 1994). Ventricle enlargement in the schizophrenic twin arises from atrophy or destruction of the adjacent neural ...