INFLUENCE OF UNILATERAL DEAFNESS ON AUDITORY-EVOKED MAGNETIC-FIELD

TO investigate the effect of unilateral deafness on central auditory m echanisms, we examined patients with unilateral deafness of various du rations. Auditory evoked magnetic fields (AEF) were recorded using a w hole-head neuromagnetometer. In patients who had unilateral deafness f or more than 3 weeks, the average N100m latency in the ipsilateral hem isphere did not differ from that in the contralateral hemisphere. In a ddition, in some patients with congenital or early onset deafness, the equivalent current dipole (ECD) moment was larger in the ipsilateral hemisphere than in the contralateral hemisphere. These findings sugges t that unilateral deafness may cause reorganization of the central aud itory pathway. They also suggest that central auditory pathway in adul ts has some plasticity, though not as much as in childhood. (C) 1998 L ippincott Williams & Wilkins.