The causal role of β-oscillations in maintaining perception-action representations

The binding of perception and action features into common representations, so-called event files, is a core mechanism supporting goal-directed behavior. Recent work using electroencephalography has presented correlational evidence linking the maintenance of perception-action representations to oscillatory activity in the β-frequency range. Here, we used transcranial alternating current stimulation (tACS) to test whether β-oscillations play a causal role in event-file maintenance. Participants performed a distractor-response binding task with a sequential prime-probe structure while receiving either active β-tACS over the left occipito-parietal cortex or a novel shunt stimulation designed to produce comparable sensory effects but substantially weaker cortical stimulation. Prime-probe intervals were varied to manipulate event-file maintenance. β-tACS did not modulate behavioral binding effects during stimulation. However, we observed a significant aftereffect on behavioral distractor-response binding after stimulation. This effect was restricted to short prime-probe intervals, where event files are typically still available, and was absent at longer intervals, where event files commonly decay. These findings provide causal evidence that β-oscillations contribute to the stabilization of perception-action representations over time. More broadly, they support the view that β-oscillations help maintain the current cognitive-motor state and preserve the status-quo in action control.