?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Auditory+event-related+potentials+(ERPs)+and+mismatch+negativity+(MMN)+in+healthy+children+and+those+with+attention-deficit+or+Tourette%2Ftic+symptoms&rft.creator=OADES%2C+Robert+D.&rft.creator=DITTMANN-BALCAR%2C+Alexandra&rft.creator=SCHEPKER%2C+Renate&rft.creator=EGGERS%2C+Christian&rft.creator=ZERBIN%2C+Dieter&rft.subject=Neurophysiology&rft.subject=Neuropsychiatry&rft.subject=Perceptual+Cognitive+Psychology&rft.description=Introduction%3A+This+study+compared+5+auditory%2C+event-related+potential+(ERP)+components+(from+P1+to+P3%2C+50+to+500+ms+post+stimulus)+after+3+tones+differing+in+pitch+and+in+rarity+presented+to+three+groups+of+children.+The+mismatch+negativity+(MMN)%2C+the+ERP+trace+of+auditory+working+memory+for+deviant+stimuli+was+also+studied.+%0A%0AMethods%3A+Topographic+recordings+were+derived+from+19+electrodes+over+the+scalp+of+12+children+with+attention-deficit%2Fhyperactivity+disorder+(ADHD)%3A+mean+10.2+years-of+age)%2C+12+healthy+controls+matched+for+age%2C+and+10+with+chronic+complex+Tic-+or+Tourette+syndrome+(TS)%2C+who+also+showed+symptoms+of+attention-deficit.+%0A%0AResults%3A+%0AFour+major+effects+are+reported%3A+%0Aa)+Shorter+ERP+latencies+were+evident+in+ADHD+children+as+early+as+100+ms+after+the+stimulus%3B+%0Ab)+Both+ADHD+and+TS+children+showed+larger+P2+component+amplitudes+than+the+controls+with+their+maxima+shifted+more+anteriorly%3B+%0A%0Ac)+Frontal+MMN+was+not+significantly+different+between+ADHD+and+healthy+controls%2C+but+the+normalised+data+showed+a+left-sided+distribution+in+the+ADHD+group+and+a+right-sided+distribution+in+the+normal+children.+Maxima+for+TS+children+was+unusually+more+posterior.+(In+adults+the+distribution+is+normally+frontal+and+bilateral.)+%0Ad)+ADHD+patients+did+not+show+the+usual+right-biased+P3+asymmetric+distribution+(nor+a+frontal+vs.+parietal+latency+difference).+%0A%0AConclusions%3A+These+results+suggest+that+ADHD+children+process+information+faster+from+the+early+N1+(c.+100+ms)+stage.+Both+groups+of+children+with+attention-deficit+symptoms+showed+a+marked+enhancement+of+the+inhibitory+phase+of+processing+in+the+auditory+cortex+marked+by+P2.+That+this+is+shown+even+after+a+standard+stimulus+indicates+an+increased+likelihood+of+unimportant+stimuli+being+further+processed+and+coming+to+control+behaviour%2C+while+stimuli+competing+for+attention+are+suppressed.+Later+indices+of+processing+(N2-P3)+showed+a+frontal+impairment+(TS)%2C+especially+in+the+right+hemisphere+(ADHD)+that+are+suggested+to+be+indicative+of+anomalous+timing+in+the+development+of+frontal+function.+%0A&rft.publisher=Elsevier&rft.date=1996&rft.type=Journal+(Paginated)&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F1168%2F2%2Fbiopsycholog.pdf&rft.identifier=++OADES%2C+Robert+D.+and+DITTMANN-BALCAR%2C+Alexandra+and+SCHEPKER%2C+Renate+and+EGGERS%2C+Christian+and+ZERBIN%2C+Dieter++(1996)+Auditory+event-related+potentials+(ERPs)+and+mismatch+negativity+(MMN)+in+healthy+children+and+those+with+attention-deficit+or+Tourette%2Ftic+symptoms.++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F1168%2F