From Idling to Action: Rethinking the Functional Role of the Alpha Rhythm

Welcome to our ABC Seminars! This seminar series is open for everyone. The talk will take place in Otakaari 3, F239a Auditorio. After the talks, coffee and pulla will be served.

The event will be also streamed via Zoom at: https://aalto.zoom.us/j/67444945844

From Idling to Action: Rethinking the Functional Role of the Alpha Rhythm

The alpha rhythm is the dominant electrophysiological signature of the awake human brain, yet its functional interpretation has changed profoundly over the past century. Following its discovery by Hans Berger, alpha oscillations were long considered a hallmark of cortical rest or “idling,” supported by their prominence during eyes-closed wakefulness and suppression during sensory engagement. Around the turn of the millennium, this view shifted with the observation that alpha activity can increase with cognitive demands, particularly in brain regions not required for the task. These findings motivated a functional-inhibition account in which alpha oscillations actively gate information processing and allocate computational resources by suppressing task-irrelevant neuronal populations.  More recent work extends this framework from the magnitude to the timing of alpha oscillations. Alpha phase structures neuronal excitability into alternating windows of inhibition and processing, producing rhythmic perceptual sampling.  Emerging evidence further links these dynamics to the oculomotor system: alpha activity interacts with frontal eye fields, parietal cortex and thalamic structures involved in controlling spatial attention and eye movements.  These findings suggest a further conceptual shift: alpha is not merely a mechanism for suppressing irrelevant processing, but a rhythm coordinating perception, attention and action through the temporal control of saccades.

References

Jensen O, Bonnefond M. (2026) The alpha rhythm: from physiology to behavior. Physiol Rev 106:1123-1159.