Too little, too late, and in the wrong place: Alpha band activity does not reflect an active mechanism of selective attention

Plamen A. Antonov* (Corresponding Author), Ramakrishna Chakravarthi, Søren K. Andersen

*Corresponding author for this work

Research output: Contribution to journalArticle

1 Citation (Scopus)
5 Downloads (Pure)

Abstract

Selective attention focuses visual processing on relevant stimuli in order to allow for adaptive behaviour despite an abundance of distracting information. It has been proposed that increases in alpha band (8 - 12 Hz) amplitude reflect an active mechanism for distractor suppression. If this were the case, increases in alpha band amplitude should be succeeded by a decrease in distractor processing. Surprisingly, this connection has not been tested directly; specifically, studies that have investigated changes in alpha band after attention-directing cues have not directly assessed the neuronal processing of distractors. We concurrently recorded alpha activity and steady-state visual evoked potentials (SSVEPs) to assess the processing of target and distractor stimuli. In two experiments, participants covertly shifted attention to one of two letter streams (left or right) to detect infrequent target letters ‘X’ while ignoring the other stream. In line with previous findings, alpha band amplitudes contralateral to the unattended location increased compared to a pre-cue baseline. However, there was no suppression of SSVEP amplitudes elicited by unattended stimuli, while there was a pronounced enhancement of SSVEPs elicited by attended stimuli. Furthermore, and crucially, changes in alpha band amplitude during attention shifts did not precede those in SSVEPs and hit rates in both experiments, indicating that changes in alpha band amplitudes are likely to be a consequence of attention shifts rather than the other way around. We conclude that these findings contradict the notion that alpha band activity reflects mechanisms that have a causal role in the allocation of selective attention.
Original languageEnglish
Article number117006
Number of pages12
JournalNeuroimage
Volume219
Early online date30 May 2020
DOIs
Publication statusPublished - 1 Oct 2020

Keywords

  • selective spatial attention
  • alpha oscillations
  • SSVEP
  • distractor suppression
  • EEG

Fingerprint Dive into the research topics of 'Too little, too late, and in the wrong place: Alpha band activity does not reflect an active mechanism of selective attention'. Together they form a unique fingerprint.

Cite this