Abnormalities of self-representation and persecutory delusions: a test of a cognitive model of paranoia.

Patients suffering from persecutory delusions exhibit information processing and social reasoning biases that have been hypothesized to have a self-protective function. In a test of this hypothesis, patients suffering from persecutory delusions who were also depressed and non-depressed deluded subjects were compared with depressed and normal controls on two indirect assessments of self-schemata: the Dysfunctional Attitudes Scale (DAS) and incidental recall of negative and positive trait words that had previously been judged to be self-descriptive or not self-descriptive. Both the depressed subjects and the deluded subjects, whether or not they were depressed, scored highly on the DAS. Like normals, both depressed and non-depressed deluded subjects endorsed more positive than negative trait words as true of themselves whereas the depressed subjects endorsed as many negative as positive trait works. Like the depressed subjects, both groups of deluded subjects recalled as many of the negative words they had endorsed as positive words, whereas the normals remembered more positive words. No such bias was observed in subjects' recall of unendorsed words. The DAS results are interpreted as clearly consistent with a defensive model of persecutory delusions whereas the incidental recall data were equivocally so.