Biased Cognition in Psychosis

Abstract

The cognitive biases associated with affective disorders have been well documented and provide extensive evidence of selective abnormalities in information processing of pathology congruent information. However in psychosis, research to date has been narrower. There is ample evidence of a ‘jumping to conclusions' reasoning bias but relatively little work on pathology congruent effects on cognitive processes such as attention and interpretation, which may be the most aetiologically important biases. In contrast in emotional disorders, such as anxiety and depression, the selective processing of pathology congruent information is now clearly implicated in the cause and maintenance of the psychopathology. In this review we focus specifically on paranoia and paranoid psychosis and ask how strongly does the evidence to date support a causal or maintaining role for belief congruent information processing biases? We review the literature across three cognitive domains: attention, reasoning, and interpretation. The evidence suggests that paranoia and paranoid psychosis is associated with selective avoidance of threat, generally reduced ‘data gathering’ and negative interpretations of hallucinations that elicit distress. To date there is little evidence specifically examining selective information processing biases of the sort that might support or exacerbate the paranoid beliefs themselves. Given the potential aetiological importance of these belief congruent biases, we call for further research to investigate pathology congruent information processing in paranoia and paranoid psychosis.