Conscious auditory perception related to long-range synchrony of gamma oscillations

TY - JOUR

T1 - Conscious auditory perception related to long-range synchrony of gamma oscillations

AU - Steinmann, Saskia

AU - Leicht, Gregor

AU - Ertl, Matthias

AU - Andreou, Christina

AU - Polomac, Nenad

AU - Westerhausen, René

AU - Friederici, Angela D

AU - Mulert, Christoph

N1 - Copyright © 2014 Elsevier Inc. All rights reserved.

PY - 2014/10/15

Y1 - 2014/10/15

N2 - While the role of synchronized oscillatory activity in the gamma-band frequency range for conscious perception is well established in the visual domain, there is limited evidence concerning neurophysiological mechanisms in conscious auditory perception. In the current study, we addressed this issue with 64-channel EEG and a dichotic listening (DL) task in twenty-five healthy participants. The typical finding of DL is a more frequent conscious perception of the speech syllable presented to the right ear (RE), which is attributed to the supremacy of the contralateral pathways running from the RE to the speech-dominant left hemisphere. In contrast, the left ear (LE) input initially accesses the right hemisphere and needs additional transfer via interhemispheric pathways before it is processed in the left hemisphere. Using lagged phase synchronization (LPS) analysis and eLORETA source estimation we examined the functional connectivity between right and left primary and secondary auditory cortices in the main frequency bands (delta, theta, alpha, beta, gamma) during RE/LE-reports. Interhemispheric LPS between right and left primary and secondary auditory cortices was specifically increased in the gamma-band range, when participants consciously perceived the syllable presented to the LE. Our results suggest that synchronous gamma oscillations are involved in interhemispheric transfer of auditory information.

AB - While the role of synchronized oscillatory activity in the gamma-band frequency range for conscious perception is well established in the visual domain, there is limited evidence concerning neurophysiological mechanisms in conscious auditory perception. In the current study, we addressed this issue with 64-channel EEG and a dichotic listening (DL) task in twenty-five healthy participants. The typical finding of DL is a more frequent conscious perception of the speech syllable presented to the right ear (RE), which is attributed to the supremacy of the contralateral pathways running from the RE to the speech-dominant left hemisphere. In contrast, the left ear (LE) input initially accesses the right hemisphere and needs additional transfer via interhemispheric pathways before it is processed in the left hemisphere. Using lagged phase synchronization (LPS) analysis and eLORETA source estimation we examined the functional connectivity between right and left primary and secondary auditory cortices in the main frequency bands (delta, theta, alpha, beta, gamma) during RE/LE-reports. Interhemispheric LPS between right and left primary and secondary auditory cortices was specifically increased in the gamma-band range, when participants consciously perceived the syllable presented to the LE. Our results suggest that synchronous gamma oscillations are involved in interhemispheric transfer of auditory information.

U2 - 10.1016/j.neuroimage.2014.06.012

DO - 10.1016/j.neuroimage.2014.06.012

M3 - SCORING: Journal article

C2 - 24945670

VL - 100

SP - 435

EP - 443

JO - NEUROIMAGE

JF - NEUROIMAGE

SN - 1053-8119

ER -