Ramping dynamics and theta oscillations reflect dissociable signatures during rule-guided human behavior

Nat Commun. 2024 Jan 20;15(1):637. doi: 10.1038/s41467-023-44571-7.

Abstract

Contextual cues and prior evidence guide human goal-directed behavior. The neurophysiological mechanisms that implement contextual priors to guide subsequent actions in the human brain remain unclear. Using intracranial electroencephalography (iEEG), we demonstrate that increasing uncertainty introduces a shift from a purely oscillatory to a mixed processing regime with an additional ramping component. Oscillatory and ramping dynamics reflect dissociable signatures, which likely differentially contribute to the encoding and transfer of different cognitive variables in a cue-guided motor task. The results support the idea that prefrontal activity encodes rules and ensuing actions in distinct coding subspaces, while theta oscillations synchronize the prefrontal-motor network, possibly to guide action execution. Collectively, our results reveal how two key features of large-scale neural population activity, namely continuous ramping dynamics and oscillatory synchrony, jointly support rule-guided human behavior.

MeSH terms

  • Brain* / physiology
  • Cues*
  • Electroencephalography
  • Humans
  • Theta Rhythm / physiology