Primary auditory cortex activation by visual speech: an fMRI study at 3 T.
Recent studies have yielded contradictory evidence on whether visual speech perception (watching articulatory gestures) can activate the human primary auditory cortex. To circumvent confounds due to inter-individual anatomical variation, we defined our subjects' Heschl's gyri and assessed blood oxygenation-dependent signal changes at 3 T within this confined region during visual speech perception and observation of moving circles. Visual speech perception activated Heschl's gyri in nine subjects, with activation in seven of them extending to the area of primary auditory cortex. Activation was significantly stronger during visual speech perception than during observation of the moving circles. Further, a significant hemisphere by stimulus interaction occurred, suggesting left Heschl's gyrus specialization for visual speech processing.
Pekkola
Johanna
J
Laboratory of Computational Engineering, Helsinki University Central Hospital, Helsinki, Finland. pekkojo@lce.hut.fi
Ojanen
Ville
V
Autti
Taina
T
Jääskeläinen
Iiro P
IP
Möttönen
Riikka
R
Tarkiainen
Antti
A
Sams
Mikko
M
D000328:Adult; D000704:Analysis of Variance; D001303:Auditory Cortex / Q000502:physiology*; D005260:Female; D006801:Humans; D008085:Lipreading; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010775:Photic Stimulation / Q000379:methods*; D013067:Speech Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology