Figure 5.

Surface renderings of MEG sources and fMRI activations. A, Source reconstruction of M170 peak measured in response to the viseme /pa/ shows that early activity related to lips movements emerges in the temporo-occipital cortex (visual motion cortex, as separately assessed by functional localizer). B, Summary of fMRI findings: parametric increase with syllable visual predictability (green blob) overlaps with the sources of M170 shown in A. Functional connectivity was assessed using PPI with visual syllable recognition rates as the psychological variable. There was a parametric increase of functional connectivity between visual motion cortex and auditory regions surrounding Heschl's gyrus (red blobs). The middle STS showed the opposite effect, i.e., a decrease of functional connectivity as a function of visual predictability (yellow blob and blue blob) when using both visual motion and auditory cortices as seed regions. C, Activity in STS also reflects the amount of prediction error, showing a signal increase for incongruent stimuli (white squares) and a signal decrease for congruent stimuli (gray squares), proportionally to visual predictability. *p < 0.05, **p < 0.01.