A neuropsychological comparison of psychotic disorder following traumatic brain injury, traumatic brain injury without psychotic disorder, and schizophrenia.

Neuropsychological functioning in individuals with psychotic disorder following traumatic brain injury (PDFTBI), traumatic brain injury without psychosis (TBIWP), and schizophrenia were compared against each other and to the means of normal subjects. It was predicted that the PDFTBI group would be similar to the schizophrenic group in patterns of deficits, but milder in severity. Compared to scores from a normal sample, the PDFTBI group scored significantly lower in intelligence, vocabulary, verbal memory, and executive functioning, while the schizophrenic group scored significantly lower in intelligence, working memory, verbal memory, visual spatial abilities, and executive functioning. No differences were found between normal subjects and the TBIWP group. Implications of our findings for the conceptualization of psychotic disorders are discussed.