Differential effects of scopolamine and amphetamine on microcomputer-based performance tests.
Scopolamine (1.0 mg) and d-amphetamine (10 mg) were administered alone and in combination to 16 subjects (medical students), randomly assigned to testing sessions in a fully crossed-over (Latin square) within-subjects design. After being practiced to stability, 9 performance tests from a menu of portable microcomputer-based tests were administered double-blind over 4 weekly treatments (including a placebo). Differential effects of drugs on performance were found. Motor and perceptual speed tests appeared enhanced by d-amphetamine and not degraded by scopolamine. Two of the five cognitive tests showed reductions with scopolamine. The findings are discussed in connection with using a menu of performance tests that can have diagnostic significance for assessment of drug treatments. The effects of scopolamine in this study and others are considered in terms of a model which implies that magnitude of performance deficit depends on performance type (cognitive, motor, self-report) and dosage level. Applying the model, we offer the following summary: below 0.15 mg scopolamine is without any effect; below 0.50 mg, the effect is limited, but can be revealed by some sensitive, complex performance tests and self-report; above 1.0 mg, the effect is likely to impact on operational efficiency.
Kennedy
R S
RS
Essex Corporation, Orlando, FL 32803.
Odenheimer
R C
RC
Baltzley
D R
DR
Dunlap
W P
WP
Wood
C D
CD
D000284:Administration, Oral; D000328:Adult; D000662:Amphetamines / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D003071:Cognition / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004526:Efficiency / Q000187:drug effects; D006801:Humans; D009041:Motion Sickness / Q000188:drug therapy / Q000453:epidemiology; D011581:Psychological Tests; D011597:Psychomotor Performance / Q000187:drug effects*; D012601:Scopolamine / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use
D000662:Amphetamines; D012601:Scopolamine