RT Journal Article
SR Electronic
T1 Sound-location specific alpha power modulation in the visual cortex in absence of visual input
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.03.15.435371
DO 10.1101/2021.03.15.435371
A1 Tzvetan Popov
A1 Nicolas Langer
A1 Bart Gips
A1 Nathan Weisz
A1 Ole Jensen
YR 2021
UL http://biorxiv.org/content/early/2021/09/23/2021.03.15.435371.abstract
AB The existence of a cortical “attentional filter” in the form of spatially selective modulation of alpha power (8-14 Hz) is a dominating hypothesis in electrophysiological studies. During auditory spatial attention hemipsheric lateralized posterior alpha modulations have been reported leading to the generalization of this hypothesis. Typically, this pattern is interpreted as reflecting a top-down endogenous mechanism for suppressing distracting input from unattended directions of sound origin. The present study on auditory spatial attention rejects this interpretation by demonstrating that alpha power modulation is closely linked to oculomotor action. Towards this end, we designed an auditory paradigm in which participants were required to attend to upcoming sounds from one of 24 loudspeakers arranged in a horizontal circular array around the head. Maintaining the location of an auditory cue was associated with a topographically modulated distribution of posterior alpha power resembling the findings known from visual attention. Multivariate analyses allowed the prediction of the sound location in the horizontal plane. Importantly, this prediction was also possible, when derived from signals capturing saccadic activity. Using eye tracking, two control experiments on visual (N=122) and auditory (N=10) spatial working memory confirmed that, in absence of any visual/auditory input, lateralization of alpha power is linked to lateralized gaze direction (± 3° visual angle). Attending to an auditory stimulus engages oculomotor and visual circuits in a topographic manner akin to the retinotopic organization in vision. We conclude that allocation of spatial attention is not sufficient to account for alpha lateralization without consideration of gaze control.Competing Interest StatementThe authors have declared no competing interest.