The Roles of Alpha Oscillations in Attentional Blink

The attentional blink (AB) refers to impaired processing of a second target (T2) when presented 200-500 msec after a first target (T1) in a rapid serial visual presentation stream. There is converging evidence that alpha oscillations (8-12 Hz) may be critical for AB performance, as they can regulate attentional control and suppress distractor interference. This study investigated the effects of neuromodulation of alpha activities via transcranial alternating current stimulation (tACS) on AB. Alpha tACS may either reduce the AB magnitude at intermediate lags by modulating inhibitory control (the suppression hypothesis) or improve AB task performance across the lags by reducing overinvestment of attentional resources on T1 and distractor processing (the diffuse attention hypothesis). In Experiment 1, alpha tACS applied over the right dorsolateral pFC (rDLPFC) during an AB task increased T2|T1 accuracy independent of the T2 lags. In Experiment 2, in-phase tACS over the rDLPFC and parietal cortex produced higher T2|T1 accuracy than antiphase tACS, again independent of T2 lag. These behavioral effects may result from alpha-tACS-induced diffuse attentional state that minimizes distractor interference of AB. The present study offers insights into the neural mechanisms underlying temporal attention and further highlights the potential utility of the neuromodulation method.