Theta and alpha power across fast and slow timescales in cognitive control

• Published in: The European journal of neuroscience 2021-07, Vol.54 (2), p.4581-4594
• Main Authors: Huycke, Pieter, Verbeke, Pieter, Boehler, C. Nico, Verguts, Tom, Mazaheri, Ali
• Format: Article
• Language: English
• Subjects: Cognitive ability; cognitive control; EEG; Electrophysiology; frontomedial theta; Learning; Oscillations; posterior alpha; Theta rhythms
• ISSN: 0953-816X; 1460-9568
• DOI: 10.1111/ejn.15320

Theta and alpha frequency neural oscillations are important for learning and cognitive control, but their exact role has remained obscure. In particular, it is unknown whether they operate at similar timescales, and whether they support different cognitive processes. We recorded EEG in 30 healthy human participants while they performed a learning task containing both novel (block‐unique) and repeating stimuli. We investigated behavior and electrophysiology at both fast (i.e., within blocks) and slow (i.e., between blocks) timescales. Behaviorally, both response time and accuracy improved (respectively decrease and increase) over both fast and slow timescales. However, on the spectral level, theta power significantly decreased along the slow timescale, whereas alpha power significantly increased along the fast timescale. We thus demonstrate that theta and alpha both play a role during learning, but operate at different timescales. This result poses important empirical constraints for theories on learning, cognitive control, and neural oscillations. Theta and alpha frequency neural oscillations are important for learning and cognitive control, but whether they operate at similar timescales, remains obscure. In this EEG study, we collect behavioral and electrophysiological data on fast (across trials) and slow (across blocks) timescales. We observe alpha changes in the fast (but not the slow) timescale; and theta changes in the slow (but not the fast) timescale. Thus, alpha and theta are both involved in learning, but on distinct timescales.