Sources of auditory selective attention and the effects of methylphenidate in children with attention-deficit/hyperactivity disorder

Background The aim of this study was to determine 1) whether abnormal auditory selective attention in children with attention-deficit/hyperactivity disorder (ADHD), as reflected in the processing negativity (PN) of the event-related potential, is related to impaired frontal functioning; and 2) how methylphenidate (MPh) affects attentional functioning in ADHD. Methods Sources of electrical brain activity were estimated in healthy control children, in ADHD children without medication, and in children with ADHD during a placebo-controlled medication trial involving MPh. Results The source models showed that the PN is generated in the auditory cortex. Children with ADHD showed less activity related to selective attention in this brain region. Administration of MPh resulted in more frontally located sources. Conclusions The results showed no evidence for an important role of the frontal cortex in abnormalities in selective attention in children with ADHD. Also, the data did not indicate that MPh normalizes brain activity in these children.