A cognitive regulatory control model of schizophrenia.

A puzzling aspect of schizophrenia concerns the relationship between negative and positive symptoms. Perspectives suggesting that they arise from the same pathophysiological process are not consistent with the numerous differences such as treatment response, and the underlying neurochemistry relevant to treatment. Explanations viewing negative and positive symptoms as independent processes or diseases cannot readily account for the typical developmental course of schizophrenia, consisting of a lengthy prodromal phase of negative followed by positive symptoms. A model of schizophrenia is presented positing that negative and positive symptoms are distinct but interrelated processes, with the former bringing forth the latter due to damaged or impaired cognitive regulatory control processes. The extensive cognitive distortions, thought form variants, and sensory perceptual experiences comprising psychosis represent a natural propensity derived from the evolution of human intelligence. To facilitate reality congruency typically necessary for adaptive functioning, cognitive regulatory control processes normally prevent these extreme variants from entering the conscious and awake state. During sleep when there is no need for reality congruency the cognitive regulatory control processes are deactivated and psychotic equivalents are expressed. Psychological defensive functioning can also deactivate these processes and allow psychosis to manifest. The negative symptoms of schizophrenia are seen as arising from diverse neural deficits that impair to varying degrees the cognitive regulatory control processes, thus producing psychosis. The pattern of neural damage determines the negative symptom profile, and the impact on cognitive regulatory control processes influences whether negative or positive symptoms dominate or exist in relatively equal proportions.