Influence of Psychotropic Drugs upon Neuropsychological Test Performance

Commonly used psychotropic medications are widely presumed to have deleterious effects on neuropsychological test performance. However, given the special difficulties of neuropsychological assessment with psychiatric populations, these effects have rarely been directly examined for differential, quantitative effects on test scores. A comprehensive neuropsychological test battery is described that assesses executive functions, memory, language comprehension, motor and sensory functions, and manual praxis. Data are presented on 233 psychiatric patients (70 females, 163 males) referred for neuropsychological assessment. All people with known or suspected brain damage were excluded, with 100 not taking any type of psychoactive medication. Comparisons between an unmedicated group and those taking the most common medications showed differences on tests of perseverative responses and praxis. No effects for nonverbal memory, simple motor functions, basic intellectual processes or visuomotor functions were noted. Implications for the assessment of people taking psychotropic medications are discussed.