Amelioration of specific working memory deficits by methylphenidate in a case of adult attention deficit/hyperactivity disorder.
Cognitive neuroscience has provided an extensive literature on the neuroanatomy and psychopharmacology of working memory. However, while it has been shown that children with attention deficit/hyperactivity disorder (AD/HD) have deficits in working memory, relatively little is known about working memory functions in adults diagnosed with AD/HD. Furthermore, it remains to be seen whether methylphenidate (Ritalin), which is used in the treatment of childhood AD/HD can improve performance deficits in adult AD/HD patients. We have used three paradigms of spatial working memory validated in cortical lesion patients, and psychopharmacological and neuroimaging studies, in order to examine the effects of methylphenidate administration in a case of an adult diagnosed with AD/HD. In the AD/HD patient at baseline testing, performance on a test of spatial recognition memory and on a task of self-ordered spatial working memory was shown to be impaired. Importantly, the impairments on the self-ordered spatial working memory task were ameliorated by an acute oral dose of methylphenidate (0.5 mg/kg). These findings provide insights into the possible neurochemical and neuroanatomical substrates of the action of methylphenidate in AD/HD and suggest a useful methodology for further research into this potentially debilitating disorder.
Mehta
M A
MA
Department of Psychiatry, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, UK. mitul.mehta2@csc.mrc.ac.uk
Calloway
P
P
Sahakian
B J
BJ
D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy* / Q000523:psychology*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use*; D002648:Child; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000188:drug therapy* / Q000209:etiology*; D008570:Memory, Short-Term / Q000187:drug effects / Q000502:physiology; D008774:Methylphenidate / Q000627:therapeutic use*
D000697:Central Nervous System Stimulants; D008774:Methylphenidate