COGNITIVE EVENT-RELATED POTENTIALS AND MAGNETIC-RESONANCE-IMAGING IN MYOTONIC-DYSTROPHY

Fourteen patients with myotonic dystrophy (MyD) were studied with mean s of an auditory ''oddball'' event-related potential (ERP) paradigm. T he results were compared with data from 53 controls. The early compone nts (N1, P2) of the ERP were not affected, whereas later components (N 2, P3), which are thought to reflect cognitive processes, were abnorma l in eight patients who were the oldest in the sample. Magnetic resona nce imaging (MRI) was performed in twelve patients and revealed, in fi ve of them, multiple focal white matter lesions. These findings, howev er, could not Se associated with neurophysiological abnormalities. It is concluded, that cognitive ERP, particularly N2 and P3 components, a re abnormal in some patients suffering from MyD. Possible etiologies o f the electrophysiological abnormalities are discussed.