Frontiers in Human Neuroscience (Mar 2010)

Gaze-direction-based MEG averaging during audiovisual speech perception

  • Lotta Hirvenkari,
  • Veikko Jousmäki,
  • Satu Lamminmäki,
  • Veli-Matti Saarinen,
  • Mikko E SAMS,
  • Riitta Hari,
  • Riitta Hari

DOI
https://doi.org/10.3389/fnhum.2010.00017
Journal volume & issue
Vol. 4

Abstract

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To take a step towards real-life-like experimental setups, we simultaneously recorded magnetoencephalographic (MEG) signals and subject’s gaze direction during audiovisual speech perception. The stimuli were utterances of /apa/ dubbed onto two side-by-side female faces articulating /apa/ (congruent) and /aka/ (incongruent) in synchrony, repeated once every 3 s. Subjects (N = 10) were free to decide which face they viewed, and responses were averaged to two categories according to the gaze direction. The right-hemisphere 100-ms response to the onset of the second vowel (N100m’) was a fifth smaller to incongruent than congruent stimuli. The results demonstrate the feasibility of realistic viewing conditions with gaze-based averaging of MEG signals.

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