Effects of single-dose methylphenidate on cognitive performance in patients with traumatic brain injury: a double-blind placebo-controlled study

OBJECTIVES: To determine the effect of a single dose of methylphenidate on the cognitive performance of patients with traumatic brain injury (TBI), and particularly on working memory and visuospatial attention. DESIGN: A double-blind placebo-controlled study. The subjects were randomly divided into an experimental group taking methylphenidate and a control group taking a placebo. SETTING: The Department of Rehabilitation Medicine of a university hospital. SUBJECTS: Eighteen subjects with TBI (16 male and two female) were enrolled. INTERVENTIONS: The patients were given 20 mg methylphenidate or a placebo. Cognitive assessments were performed at three times: before the medication as a baseline, 2 h after medication and at follow-up (48 h later). MAIN MEASURES: Cognitive assessments consisted of working memory tasks and endogenous visuospatial attention tasks designed using SuperLabPro 2.0 software. Response accuracy and reaction time were measured. RESULTS: There were significant improvements in response accuracy in the methylphenidate group compared with the placebo group for both the working memory and visuospatial attention tasks. A significant decrease in the reaction time was also observed in the methylphenidate group only for the working memory task. CONCLUSIONS: The administration of single-dose methylphenidate has an effect in improving cognitive functioning following a TBI. The effects were most prominent regarding the reaction time of the working memory.