Objective: This study used eye movement tests to examine whether frontal lobe dysfunction is present in delusional disorder.
Method: Smooth pursuit and voluntary saccadic eye movements of 15 delusional patients, 40 schizophrenic patients, and 40 normal subjects were recorded and analyzed statistically.
Results: The schizophrenic patients differed significantly from the normal subjects in some smooth pursuit eye movement characteristics, whereas both the schizophrenic and the delusional patients showed more saccades than the normal subjects during the smooth pursuit test. The delusional patients and normal subjects differed significantly in some voluntary saccadic eye movement characteristics.
Conclusions: The data support the idea of a biological dysfunction in eye tracking in delusional disorder.