EVOKED-POTENTIALS RECORDED FROM THE AUDITORY-CORTEX IN MAN - EVALUATION AND TOPOGRAPHY OF THE MIDDLE LATENCY COMPONENTS

The goal of this study is to determine and localize the generators of different components of middle latency auditory evoked potentials (MLA EPs) through intracerebral recording in auditory cortex in man (Heschl 's gyrus and planum temporale). The present results show that the gene rators of components at 30, 50, 60 and 75 msec latency are distributed medio-laterally along Heschl's gyrus. The 30 msec component is genera ted in the dorso-postero-medial part of Heschl's gyrus (primary area) and the 50 msec component is generated laterally in the primary area. The generators of the later components (60-75 msec) are localized in t he lateral part of Heschl's gyrus that forms the secondary areas. The localization of N100 generators is discussed.