SCHIZOPHRENIA, SENSORY GATING, AND NICOTINIC RECEPTORS

A series of human and animal investigations has suggested that altered expression and function of the alpha 7-nicotinic cholinergic receptor may be responsible for the auditory sensory gating deficit characteri zed in schizophrenia patients and their relatives as diminished suppre ssion of an auditory-evoked response (P50) to repeated stimuli. This f inding, in conjunction with evidence for familial transmission of this sensory gating deficit; suggests a pathogenic role of the gene for th e alpha 7-nicotinic receptor in schizophrenia. This article considers the possible effects of this dysfunction in a broader context. Not onl y is this dysfunction consistent with difficulties in sensory gating, but it might also predispose patients to problems with learning effici ency and accuracy. Such learning problems could underlie schizophrenia patients' delusional thinking, hallucinations, and social dysfunction , In addition, heavy smoking in many schizophrenia patients is consist ent with the high concentration of nicotine necessary to activate the receptor and with the receptor's extremely rapid desensitization. Fina lly, the receptor's possible role in cell. growth and differentiation should be considered in connection with developmental deficits and oth er cellular abnormalities in schizophrenia.