title: Cognitive effects of immediate-release methylphenidate in children with attention-deficit/hyperactivity disorder.
abstract: A growing body of literature has examined the cognitive effects of immediate-release methylphenidate in children with attention-deficit/hyperactivity disorder (ADHD). However, a clear understanding of the types and magnitude of such effects are difficult to discern from such a large and varied collection of published reports. This review evaluated a total of 40 relevant placebo-controlled studies published since Rapport and Kelly's [1993. Psychostimulant effects on learning and cognitive function. In: Matson, J.L. (Ed.), Handbook of Hyperactivity in Children. Allyn & Bacon, Boston, pp. 97-136] original review of cognitive effects of methylphenidate in children with ADHD. Of these published studies, 63.5% identified some improvement in cognitive function following methylphenidate treatment. Methylphenidate improved performance on saccadic eye movement, planning/cognitive flexibility, attention/vigilance, and inhibitory control tasks in 83.3%, 71.4%, 70.6%, and 69.7% of studies, respectively. A total 58.3% and 50% of studies that evaluated the effect of methylphenidate on tasks of memory and working memory/divided attention, respectively, noted improvement. Variability of findings across studies may be explained by differential effects of methylphenidate on brain function, intra- and inter-individual variability in medication response, methodological limitations, and problems associated with repeated neuropsychological assessment and metric properties of commonly utilised neuropsychological instruments.
authors.affiliation: Department of Psychology, Clinical Division, University of Connecticut, 406 Babbidge Road, Unit 1020, Storrs, CT 06269-1020, USA.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Pietrzak
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Mollica
authors.forename: Paul
authors.initials: P
authors.lastname: Maruff
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Snyder
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy* / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D003071:Cognition / Q000187:drug effects*; D006801:Humans; D008774:Methylphenidate / Q000494:pharmacology* / Q000627:therapeutic use*; D009483:Neuropsychological Tests
chemical_list: D008774:Methylphenidate