Transient neural network dynamics in cognitive ageing

Neurobiol Aging. 2021 Sep;105:217-228. doi: 10.1016/j.neurobiolaging.2021.01.035. Epub 2021 May 14.

Abstract

It is important to maintain cognitive function in old age, yet the neural substrates that support successful cognitive ageing remain unclear. One factor that might be crucial, but has been overlooked due to limitations of previous data and methods, is the ability of brain networks to flexibly reorganize and coordinate over a millisecond time-scale. Magnetoencephalography (MEG) provides such temporal resolution, and can be combined with Hidden Markov Models (HMMs) to characterise transient neural states. We applied HMMs to resting-state MEG data from a large cohort (N=595) of population-based adults (aged 18-88), who also completed a range of cognitive tasks. Using multivariate analysis of neural and cognitive profiles, we found that decreased occurrence of "lower-order" brain networks, coupled with increased occurrence of "higher-order" networks, was associated with both increasing age and decreased fluid intelligence. These results favour theories of age-related reductions in neural efficiency over current theories of age-related functional compensation, and suggest that this shift might reflect a stable property of the ageing brain.

Keywords: Ageing; Canonical correlation analysis; Cognition; Fluid intelligence; Hidden Markov model; Magnetoencephalography.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Cognition*
  • Cognitive Aging / physiology*
  • Cohort Studies
  • Female
  • Humans
  • Magnetoencephalography
  • Male
  • Markov Chains
  • Middle Aged
  • Nerve Net / physiology*
  • Rest / physiology
  • Young Adult