Figure 1.

Neuroanatomical model of auditory facilitation by concurrent visual input and related predictions. A, Two anatomical pathways are proposed for the routing of visual information (green arrows) to auditory areas (A) (red arrows representing routing of auditory information): pathway (1) is a direct corticocortical pathway from visual cortices (V) and pathway (2) is a feedback pathway from multisensory STS. B, Time course of evoked components for auditory (red), visual (green), and AV (blue) stimuli. Neuronal facilitation is assessed by measuring amplitude reduction and latency anticipation of the M100A peak in the AV–V versus A conditions. C, Predictions on the origin of M100A facilitation as a function of (1) viseme dependency and (2) mismatch when audio and visual syllables are not congruent.