In congenital deafness the central auditory system is completely deprived of it’s adequate input. That results in cross-modal reorganization of the auditory cortex both in animal models and in deaf humans. Deafness constitutes a unique opportunity to study the capacity of cortical plasticity within and between modalities, since hearing can be later restored through neuro-prostheses inserted at the peripheral level (even in humans). Speakers of the proposed symposium will elucidate the determinants of these reorganizations by contrasting their specificity at several levels, from anatomy to behavior in both animal models and humans. Cross-modal reorganization is highly specific within the reorganized modality. Supranormal visual performance in deaf is demonstrated for particular functions and is not found in other ones. The reorganization at the cortical level is area-specific, some auditory areas are activated in processing of certain visual and somatosensory stimuli, some are not. Finally, the cortical network for multisensory processing is highly dependent on the onset and duration of recovery of the auditory function in cochlear-implanted deaf subjects. To understand these cross-modal reorganizations is of cardinal interest for basic science as well as for the therapy of profoundly deaf patients.

Speakers:
A. Kral (University Medical Center Hamburg-Eppendorf)
S.G.Lomber (Universtiy. Western Ontario, U.S.)
A. Sharma (University of Boulder, U.S.)
P. Barone (University Paul Sabatier, Toulouse, France)
N. Skotara (University of Hamburg, Germany)