Global attentional selection of visual features is not associated with selective modulation of posterior alpha‐band activity

Abstract

AbstractAttending to a single feature, such as color or motion, leads to global modulation of neural processing associated with the representation of the attended features. Alpha‐band modulations are hypothesized to be a marker (and even a mechanism) of the modulation of neural processing. By adopting a previously used attentional shifting paradigm, we examined whether alpha‐band dynamics are linked to sustained Feature‐Based‐Attentional (FBA) selection. For this purpose, we presented task‐irrelevant flickering random dot kinematograms (RDKs) in the periphery that either did or did not share the to‐be‐attended color of centrally presented task‐relevant RDKs and should thus be subject to global FBA selection. Steady‐state visual evoked potentials (SSVEPs) and alpha‐band activity associated with these task‐irrelevant RDKs were analyzed to quantify FBA modulation. Overall, the SSVEP results replicated previous findings: relative to a pre‐cue baseline, SSVEP amplitudes for peripheral RDKs were significantly enhanced when these RDKs shared the to‐be‐attended color of the central RDKs and were not modulated when they shared the centrally to‐be‐ignored color. Nevertheless, there were no differences in alpha‐band amplitude modulations between signals recorded contralateral to the RDKs sharing the centrally attended color and RDKs sharing the centrally ignored color. Hence, alpha‐band modulations seem not to index the sustained global selection of attended over unattended feature values within the same feature dimension.