Variability and task-responsiveness of electrophysiological dynamics: Scale-free stability and oscillatory flexibility

Soren Wainio-Theberge, Annemarie Wolff, Javier Gomez-Pilar, Jianfeng Zhang, Georg Northoff

Research output: Contribution to journalArticlepeer-review

Abstract

Cortical oscillations and scale-free neural activity are thought to influence a variety of cognitive functions, but their differential relationships to neural stability and flexibility has never been investigated. Based on the existing literature, we hypothesize that scale-free and oscillatory processes in the brain exhibit different trade-offs between stability and flexibility; specifically, cortical oscillations may reflect variable, task-responsive aspects of brain activity, while scale-free activity is proposed to reflect a more stable and task-unresponsive aspect. We test this hypothesis using data from two large-scale MEG studies (HCP: n = 89; CamCAN: n = 195), operationalizing stability and flexibility by task-responsiveness and spontaneous intra-subject variability in resting state. We demonstrate that the power-law exponent of scale-free activity is a highly stable parameter, which responds little to external cognitive demands and shows minimal spontaneous fluctuations over time. In contrast, oscillatory power, particularly in the alpha range (8–13 Hz), responds strongly to tasks and exhibits comparatively large spontaneous fluctuations over time. In sum, our data support differential roles for oscillatory and scale-free activity in the brain with respect to neural stability and flexibility. This result carries implications for criticality-based theories of scale-free activity, state-trait models of variability, and homeostatic views of the brain with regulated variables vs. effectors.

Original languageEnglish
Article number119245
JournalNeuroImage
Volume256
DOIs
Publication statusPublished - Aug 1 2022
Externally publishedYes

Keywords

  • Cortical oscillations
  • Flexibility
  • MEG
  • Neural variability
  • Scale-free activity
  • Stability

ASJC Scopus subject areas

  • Neurology
  • Cognitive Neuroscience

Fingerprint

Dive into the research topics of 'Variability and task-responsiveness of electrophysiological dynamics: Scale-free stability and oscillatory flexibility'. Together they form a unique fingerprint.

Cite this