The research deals with the possible role of the essentially monosynaptic bidirectional corticocortical connections between occipitotemporo-parietal association cortical areas and frontal areas in the genesis of some contingent negative variation (CNV) components, especially on the supramodal dorsolateral prefrontal regions. With standard averaging and topographic mapping methods of analysis, the multicomponent CNV complex formation was examined in 7 patients with extensive frontal cortex ablations exactly identified through CTIMRI examinations, and in 10 normal subjects. On the scalp over the ablated frontocortical areas, no consistent post-warning auditory N100 a-b-c, P200, P300, early and late CNV components were recordable. The hypothesis is proposed that the bidirectional ipsilateral long-distance pathways which interconnect uni-polymodal occipito-temporo-parietal cortical areas to prefrontal ones, in particular the arcuate-superior longitudinal and superior/inferior occipito-frontal fasciculi, play an important role in the genesis of several CNV complex components, especially the multicomponent post-S1 auditory N100. The posteroanterior sequential latency differences of these neurocognitive components, roughly measured along the scalp or on MRI imagings, is probably accounted for by the transcortical ipsilateral conduction time of about 1 cm/ms (10 m/s).
- Auditory N100
- Cognitive potentials
- Contingent negative variation
- Human prefrontal ablations
- Ipsilateral corticocortical interconnections
- Long bidirectional fasciculi
ASJC Scopus subject areas