Inverse relation between clinical distractibility and Stroop interference in functional psychoses

INTRODUCTION: Many patients with psychotic disorders appear distractible. Some theories propose that distractibility causes psychotic symptoms, others propose the reverse. We tested these theories by assessing relations between psychotic symptoms, Stroop interference, and clinical distractibility in patients with schizophrenia or affective psychoses. METHODS: We rated clinical distractibility in patients with acute schizophrenia or affective psychoses and measured their Stroop interference in a single trial colour-naming task. RESULTS: Clinical distractibility related inversely to Stroop interference. Stroop interference was small in drug-naive patients with schizophrenia, but normal in those receiving treatment. Patients with affective psychoses showed the opposite pattern. CONCLUSIONS: The abnormality of attention that clinicians rate as “distractibility” is probably the opposite—attentional capture. Abnormal attention neither results from nor causes psychotic symptoms. Rather, it is an independent correlate of pathophysiology in functional psychoses that merits assessment and treatment in its own right