The role of alpha oscillations in spatial attention: limited evidence for a suppression account

doi:10.1016/j.copsyc.2018.11.001

Current Opinion in Psychology

Volume 29, October 2019, Pages 34-40

https://doi.org/10.1016/j.copsyc.2018.11.001 Get rights and content

Highlights

•
Alpha-band (8–12 Hz) oscillations precisely track the locus covert spatial attention.
•
Alpha-band activity tracks the temporal dynamics of covert orienting.
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Evidence is lacking for the view that alpha-band oscillations suppress irrelevant input during spatial selection.
•
Alpha-band oscillations may mediate direct enhancement of input at attended locations.

Covert spatial attention allows us to prioritize visual processing at relevant locations. A fast growing literature suggests that alpha-band (8–12 Hz) oscillations play a key role in this core cognitive process. It is clear that alpha-band activity tracks both the locus and timing of covert spatial orienting. There is limited evidence, however, for the widely embraced view that alpha oscillations suppress irrelevant visual information during spatial selection. Extant evidence is equally compatible with an account in which alpha activity enables spatial selection through signal enhancement rather than distractor suppression. Thus, more work is needed to characterize the computational role of alpha activity in spatial attention.

Section snippets

Alpha-band activity tracks covert spatial attention

Our capacity to process visual information is limited. Thus, we must prioritize processing at relevant locations. Covert spatial attention allows us to select relevant locations without moving our eyes, enhancing processing at the attended location [1]. Human electroencephalogram (EEG) studies have long linked alpha-band (8–12 Hz) oscillations with covert spatial attention [2, 4, 5, 6, 7]. When attention is deployed to one side of space, posterior alpha-band power is reduced at electrodes over

Does alpha-band activity suppress irrelevant visual inputs? The jury is out

What computational role does alpha activity play in covert attention? The modal view is that alpha activity mediates the suppression or gating of irrelevant visual inputs [2,3^••,14, 15, 16]. This view falls in line with the consensus that distractor exclusion is a critical component of visual attention [17]. However, it is broadly acknowledged that improved perception at a relevant location can also occur via signal enhancement, which directly improves processing at attended locations [1,18].

Conflict of interest statement

Nothing declared.

References and recommended reading

Papers of particular interest, published within the period of review, have been highlighted as:

• of special interest
•• of outstanding interest

Acknowledgement

This work was supported by National Institute of Mental Health [grant number 2R01MH087214-06A1].

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View full text

The role of alpha oscillations in spatial attention: limited evidence for a suppression account

Highlights

Section snippets

Alpha-band activity tracks covert spatial attention

Does alpha-band activity suppress irrelevant visual inputs? The jury is out

Conflict of interest statement

References and recommended reading

Acknowledgement

Vis Res

Neuropsychologia

Psychol Sci

Eur J Neurosci

Neuron

Neuron

Psychophysiology

J Cogn Neurosci

J Neurosci

J Neurosci

Trends Cogn Sci

The role of alpha-band brain oscillations as a sensory suppression mechanism during selective attention

Front Psychol

Shaping functional architecture by oscillatory alpha activity: gating by inhibition

Front Hum Neurosci

Anticipatory biasing of visuospatial attention indexed by retinotopically specific α-band electroencephalography increases over occipital cortex

J Neurosci

α-band electroencephalographic activity over occipital cortex indexes visuospatial attention bias and predicts visual target detection

J Neurosci

Increases in alpha oscillatory power reflect an active retinotopic mechanism for distracter suppression during sustained visuospatial attention

J Neurophysiol

Mechanisms of selective inhibition in visual spatial attention are indexed by α-band EEG synchronization

Eur J Neurosci

Decoding and reconstructing color from responses in human visual cortex

J Neurosci

Visual attention mitigates information loss in small- and large-scale neural codes

Trends Cogn Sci

Decoding and reconstructing the focus of spatial attention from the topography of alpha-band oscillations

J Cogn Neurosci

EEG and MEG: relevance to neuroscience

Neuron

The importance of ignoring: alpha oscillations protect selectivity

Curr Dir Psychol Sci

The many characters of visual alpha oscillations

Eur J Neurosci

The roles of cortical oscillations in sustained attention

Trends Cogn Sci