Continuous performance tests in schizophrenic patients: stimulus and medication effects on performance

Psychiatry Res. 1991 Apr;37(1):47-56. doi: 10.1016/0165-1781(91)90105-x.


Medicated (n = 17) and unmedicated (n = 17) schizophrenic patients were compared to a normal control group (n = 19) on their performance on auditory and visual versions of the Continuous Performance Test (CPT). Within each stimulus modality, performance was examined on lexical and nonlexical target stimuli. Neuromotor competence was assessed on the basis of motor speed and proficiency. Normal subjects made fewer errors of all types than schizophrenic patients. Unmedicated patients made significantly more errors on nonlexical stimuli than medicated patients, with medication status found not to be associated with stimulus modality effects. Motor proficiency was associated with CPT performance in the medicated patients, but not the unmedicated ones, although this difference in correlations did not account for the group differences between these patients. The authors discuss the implications of these data for the type of cognitive and attentional functions that are affected by medication in schizophrenia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arousal / drug effects*
  • Attention / drug effects*
  • Auditory Perception / drug effects
  • Benztropine / administration & dosage*
  • Benztropine / adverse effects
  • Female
  • Haloperidol / administration & dosage*
  • Haloperidol / adverse effects
  • Humans
  • Male
  • Neuropsychological Tests
  • Psychiatric Status Rating Scales
  • Psychomotor Performance / drug effects*
  • Schizophrenia / drug therapy*
  • Schizophrenic Psychology*
  • Verbal Learning / drug effects
  • Visual Perception / drug effects


  • Benztropine
  • Haloperidol