OBJECTIVE: The goal of this investigation was to study the relationship
between information-processing deficits and thought disorder in
schizophrenic patients. METHOD: Fifty-two subjects diagnosed with
schizophrenia were administered tests of information processing and thought
disorder. The information-processing tests included visual backward masking
and prepulse inhibition of the startle reflex. Thought disorder was
measured with the Magical Ideation Scale, the Scale for the Assessment of
Positive Symptoms, the alogia subscale of the Scale for the Assessment of
Negative Symptoms, and the Ego Impairment Index- human experience variable
and its subcomponents derived from the Rorschach. RESULTS: Elevated poor
responses on the Ego Impairment Index- human experience variable were
significantly correlated with information-processing deficits. In a
simultaneous multiple regression, the auditory prepulse inhibition measure
was the best predictor of poor responses on the Ego Impairment Index-human
experience variable. CONCLUSIONS: The results suggest a correlative
relationship between information-processing deficits and thought disorder.
The relationship is most apparent when highly sensitive measures of both
information processing and thought disorder are used. Furthermore, the
prediction of poor responses on the Ego Impairment Index-human experience
variable by auditory prepulse inhibition is important, since the neural
circuitry of prepulse inhibition is known and involves the modulatory
influences of the cortical-striatal-pallidal-thalamic circuit. These
findings lend support to the hypothesis that information-processing
failures are associated with cognitive fragmentation and thought disorder.
More speculatively, these results allow us to hypothesize that impairments
in part of the cortical-striatal-pallidal-thalamic circuit may lead to
thought disorder, as well as prepulse inhibition deficits.
Abstract Teaser