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bioRxiv · 10.1101/2020.10.08.331637

Aging alters the mediating effect of endogenous GABA on the interaction between functional connectivity and motor-state transitions.

Heise, K.-F.·Rueda Delgado, L. M.·Chalavi, S.·King, B. R.·Santos Monteiro, T.·Edden, R. A. E.·Mantini, D.·Swinnen, S. P.
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Abstract

The flexible adjustment of ongoing behavior challenges the nervous systems dynamic control mechanisms and has shown to be specifically susceptible to age-related decline. Previous work links endogenous gamma-aminobutyric acid (GABA) with behavioral efficiency across perceptual and cognitive domains, with potentially the strongest impact on those behaviors that require a high level of dynamic control. Based on the integrated analyses of behavior and modulation of interhemispheric phase-based connectivity during dynamic motor state transitions and endogenous GABA concentration, we provide converging evidence for age-related differences in the behaviorally more beneficial state of endogenous GABA concentration. We suggest that the increased interhemispheric connectivity seen in the older adults represents a compensatory mechanism caused by rhythmic entrainment of neural populations in homotopic motor cortices. This mechanism appears to be most relevant in the presence of a less optimal tuning of the inhibitory tone to uphold the required flexibility of behavioral action.

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Heise, K.-F., Rueda Delgado, L. M., Chalavi, S., King, B. R., Santos Monteiro, T., Edden, R. A. E., Mantini, D., Swinnen, S. P.. 2020-10-09. Aging alters the mediating effect of endogenous GABA on the interaction between functional connectivity and motor-state transitions.. https://doi.org/10.1101/2020.10.08.331637

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