Single Dose Methylphenidate Does Not Impact on Attention and Decision Making in Healthy Medical Students

Abstract

Background: Methylphenidate (MPH) is effective for the treatment of Attention Deficit Hyperactivity Disorder (ADHD) and used illicitly by healthy adults, even though evidence concerning its efficacy is inconsistent and equivocal. We studied the effect of MPH on two cognitive tasks (attention/inhibition and decision making), a subjective rating scale and heart rate and blood pressure.

Methods: Forty five medical students, ages 20 - 30, who denied past or present ADHD symptoms, participated in this double-blind, randomized, placebo controlled cross-over experiment. Data collection was conducted in two sessions, each 2.5 hours, two weeks apart. At the beginning of each session, the subjects completed a Visual Analogue Scale (VAS) quantifying their feelings regarding present mental and emotional state and then administered either placebo or MPH (0.3 mg/kg). Ninety minutes later, they again completed the VAS and were administered two cognitive tasks: Test of Variables of Attention (TOVA) and the modified Cambridge Gambling Test (mCGT). We found no differences with or without MPH for reaction time, response time variability, number of commissions and omissions in the TOVA or for quality, sum of gamble and reaction time for the mCGT.

Results: No differences were observed between sessions with or without methylphenidate for reaction time, response time variability, number of commissions and omissions in the TOVA or for quality, sum of gamble and reaction time for the mCGT. Furthermore, no differences were observed in subjective rating on the VAS. Small, non-significant increases in blood pressure were documented. A practice effect was noted for the two consecutive sessions regardless of intervention.

Conclusions: In this study, MPH did not affect sustained attention and decision making in healthy young adults, did not alter the subjective perception of their mental and emotional state nor influence heart rate or blood pressure.




J Neurol Res. 2012;2(6):227-234
doi: https://doi.org/10.4021/jnr143w