We examined the effect of methylphenidate (Mph) on inhibition and several other cognitive abilities in 43 adults with Attention Deficit Hyperactivity Disorder (ADHD) by use of Conners’ Continuous Performance Test (CPT) and the Change Task (ChT), an extension of the Stop Signal Test (SST). In a double blind, cross-over, placebo controlled study with Mph, tests were administered during the third week of individually titrated treatment with Mph (maximum dose 1 mg / kg / day) and during the third week of treatment with placebo. We established large medication effects for commission errors, standard error of mean reaction time, and attentiveness on the CPT, as well as moderate medication effects for mean reaction time on the CPT and response re-engagement speed on the ChT. For Stop Signal Reaction Time (SSRT) on the ChT, we also established large effects of Mph, but only in a group of participants who showed slow SSRTs on placebo. Mph indeed ameliorates inhibition, which is the core problem of ADHD, and certain other cognitive abilities in adults with ADHD.

, , , , , ,
hdl.handle.net/1765/10171
Neuropsychology, Development and Cognition. Section A: Journal of Clinical and Experimental Neuropsychology
Department of Psychology

Boonstra, M., Kooij, S., Oosterlaan, J., Sergeant, J., & Buitelaar, J. (2005). Does Methylphenidate Improve Inhibition and Other Cognitive Abilities in Adults with Childhood-Onset ADHD?. Neuropsychology, Development and Cognition. Section A: Journal of Clinical and Experimental Neuropsychology. Retrieved from http://hdl.handle.net/1765/10171