Causal links between parietal alpha activity and spatial auditory attention.

Yuqi Deng,Robert Mg Reinhart,Barbara G Shinn-Cunningham,Inyong Choi

doi:10.7554/elife.51184

Yuqi Deng, Robert Mg Reinhart + Show 2 more

Open Access

https://doi.org/10.7554/elife.51184

Copy DOI

Abstract

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.

Highlights

1.1 Parietal alpha activity changes with the focus of spatial attentionParietal cortex interacts with frontal cortex to control spatial attention in both vision and audition[1,2]
Functional magnetic resonance imaging reveals a series of retinotopically mapped regions ascending along the intraparietal sulcus (IPS), which are biased towards representing contralateral exocentric space[3,4]
When listeners attended to the left, performance dropped as expected, from 79.81% correct in continuous trials to 56.84% correct in the switching trials (Z(17) = 3.66, Padj < 0.001, Wilcoxon signed rank test corrected for multiple comparisons)

Summary

Introduction

1.1 Parietal alpha activity changes with the focus of spatial attention. Parietal cortex interacts with frontal cortex to control spatial attention in both vision and audition[1,2]. While the earlier mapped regions are strongly engaged only by vision, the higher maps are recruited when participants engage spatial auditory attention[5]. Alpha oscillations (8-14 Hz) are associated with a range of neural functions[6,7]. Parietal cortex generates strong alpha oscillations measurable using electro- and magneto-encephalography (EEG and MEG)[8,9,10]. When listeners focus visual attention, alpha power lateralizes, increasing in the parietal hemisphere ipsilateral to the direction of attention and decreasing contralaterally[11]

Objectives

Methods

Results

Conclusion