Article

Studies in patients with an isolated, congenital agenesis of the corpus callosum
have documented potentials and limits of brain plasticity. Literature suggests
that early reorganization mechanisms can compensate for the absence of the corpus
callosum in unisensory tasks that involve interhemispheric transfer. It is
unknown, however, how the congenitally acallosal brain processes multisensory
information, which presumably requires interhemispheric transfer of
modality-specific input. Therefore, we tested five patients with total and one
patient with partial agenesis of the corpus callosum in a visuotactile
interference task (the "crossmodal congruency task") with uncrossed and crossed
hands and compared their performance to that of 31 healthy controls. We found
that congruency effects followed the hands in space not only in healthy, but also
in congenitally acallosal individuals. Remarkably, this was also true when
patients' hands crossed the vertical visual meridian and stimuli were presented
at the same hand. These results suggest that callosal connectivity is not
required for remapping of visuotactile space. We conclude that early brain
plasticity allows for compensation of the developmental absence of the corpus
callosum in a visuotactile interference task.
CI - Copyright (c) 2011 Elsevier Ltd. All rights reserved.

Langue : ANGLAIS