The "benefits" of distractability: Mechanisms underlying increased Stroop effects in schizophrenia

Recent studies of selective attention in schizophrenia patients suggest a p articular pattern of single-trial Stroop performance: increased facilitatio n but not interference in reaction times (RTs), combined with increased err or interference. Our Stroop task analysis suggests that this pattern can be explained by a selective attention deficit if one accounts for (1) perform ance in the congruent condition; (2) the nature of the neutral stimulus; (3 ) the relationship between accuracy and RT; and (4) response set effects, T o test these hypotheses, we examined Stroop performance in 40 DSM-IV schizo phrenia patients and 20 healthy control subjects, using a range of neutral stimuli (color patches, noncolor words, color words not in the response set ), The findings confirmed several of our predictions and the results were c onsistent with the hypothesis that abnormal Stroop performance in schizophr enia reflects a failure to adequately attend to the task-appropriate stimul us dimension (color), This inattention affects both the congruent and incon gruent conditions and multiple points in the information processing pathway .