Cortical oscillations related to processing congruent and incongruent grapheme-phoneme pairs.
In this study, we investigated changes in cortical oscillations following congruent and incongruent grapheme-phoneme stimuli. Hiragana graphemes and phonemes were simultaneously presented as congruent or incongruent audiovisual stimuli to native Japanese-speaking participants. The discriminative reaction time was 57 ms shorter for congruent than incongruent stimuli. Analysis of MEG responses using synthetic aperture magnetometry (SAM) revealed that congruent stimuli evoked larger 2-10 Hz activity in the left auditory cortex within the first 250 ms after stimulus onset, and smaller 2-16 Hz activity in bilateral visual cortices between 250 and 500 ms. These results indicate that congruent visual input can modify cortical activity in the left auditory cortex.
Herdman
Anthony T
AT
The Rotman Research Institute at Baycrest Centre, 3560 Bathurst Street, Toronto, Ont., Canada M6A 2E1. aherdman@rotman-baycrest.on.ca
Fujioka
Takako
T
Chau
Wilkin
W
Ross
Bernhard
B
Pantev
Christo
C
Picton
Terence W
TW
D000161:Acoustic Stimulation; D001303:Auditory Cortex / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D010364:Pattern Recognition, Visual; D010775:Photic Stimulation; D013067:Speech Perception; D014793:Visual Cortex / Q000502:physiology*