Evidence of a visual-to-auditory cross-modal sensory gating phenomenon as reflected by the human P50 event-related brain potential modulation.
We investigated the existence of a cross-modal sensory gating reflected by the modulation of an early electrophysiological index, the P50 component. We analyzed event-related brain potentials elicited by audiovisual speech stimuli manipulated along two dimensions: congruency and discriminability. The results showed that the P50 was attenuated when visual and auditory speech information were redundant (i.e. congruent), in comparison with this same event-related potential component elicited with discrepant audiovisual dubbing. When hard to discriminate, however, bimodal incongruent speech stimuli elicited a similar pattern of P50 attenuation. We concluded to the existence of a visual-to-auditory cross-modal sensory gating phenomenon. These results corroborate previous findings revealing a very early audiovisual interaction during speech perception. Finally, we postulated that the sensory gating system included a cross-modal dimension.
Lebib
Riadh
R
Neurosciences Cognitives et Imagerie Cérébrale, LENA CNRS UPR 640, Groupe hospitalier Pitié-Salpêtrière, 47 bd de l'Hôpital, 75651 Paris Cedex 13, France. riadh.lebib@chups.jussieu.fr
Papo
David
D
de Bode
Stella
S
Baudonnière
Pierre Marie
PM
D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D000704:Analysis of Variance; D001921:Brain / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods