Interhemispheric callosal transfer in adults with attention-deficit/hyperactivity disorder: an event-related potential study.
Although subtypes of attention-deficit/hyperactivity disorder have been recognized for some time, few studies have investigated neurophysiological differences that may reflect these. Here, adults with attention-deficit/hyperactivity disorder-inattentive type, attention-deficit/hyperactivity disorder-combined type and controls performed a simple reaction time laterality task (the Poffenberger) during 128-channel electroencephalography recording. Visual-evoked potentials were used to calculate interhemispheric transfer times. As expected for controls, mean right-to-left transfer time was faster than mean left-to-right transfer. No significant asymmetry was, however, found for clinical groups. Compared with controls, attention-deficit/hyperactivity disorder-combined participants demonstrated significantly faster left-to-right transfer, whereas attention-deficit/hyperactivity disorder-inattentive participants had significantly slower right-to-left transfer. These findings support the existence of functional differences between attention-deficit/hyperactivity disorder subtypes, and suggest that the right hemisphere dysfunction theory of attention-deficit/hyperactivity disorder may only be applicable to those without hyperactive symptoms.
Rolfe
Mei Hsin Suzanne
MH
Department of Psychology, Research Centre for Cognitive Neuroscience, University of Auckland, Auckland, New Zealand.
Kirk
Ian J
IJ
Waldie
Karen E
KE
D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000503:physiopathology*; D003337:Corpus Callosum / Q000503:physiopathology*; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D009434:Neural Pathways / Q000503:physiopathology*; D009483:Neuropsychological Tests; D011930:Reaction Time / Q000502:physiology