Both visual and auditory spatial selective attention result in lateralized alpha (8-14 Hz) oscillatory power in parietal cortex: alpha increases in the hemisphere ipsilateral to attentional focus. Brain stimulation studies suggest a causal relationship between parietal alpha and suppression of the representation of contralateral visual space. However, there is no evidence that parietal alpha controls auditory spatial attention. Here, we performed high definition transcranial alternating current stimulation (HD-tACS) on human subjects performing an auditory task in which they directed attention based on either spatial or nonspatial features. Alpha (10 Hz) but not theta (6 Hz) HD-tACS of right parietal cortex interfered with attending left but not right auditory space. Parietal stimulation had no effect for nonspatial auditory attention. Moreover, performance in post-stimulation trials returned rapidly to baseline. These results demonstrate a causal, frequency-, hemispheric-, and task-specific effect of parietal alpha brain stimulation on top-down control of auditory spatial attention.
Data are available from Dryad at https://dx.doi.org/10.5061/dryad.c031nv7
Data from: Causal links between parietal alpha activity and spatial auditory attentionDryad Digital Repository, doi:10.5061/dryad.c031nv7.
- Barbara G Shinn-Cunningham
- Barbara G Shinn-Cunningham
- Robert MG Reinhart
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: All subjects gave informed consent, as approved by the Boston University Charles River Campus IRB, under protocol 3597E.
- Huan Luo, Peking University, China
© 2019, Deng et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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