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bioRxiv · 10.1101/2020.07.29.223180

Preferential activation of the posterior Default-Mode Network with sequentially predictable task switches.

Arana-Oiarbide, G.·Daws, R. E.·Lorenz, R.·Violante, I. R.·Hampshire, A.
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Abstract

The default-mode network (DMN) has been primarily associated with internally-directed and self-relevant cognition. This perspective is expanding to recognise its importance in executive behaviours like switching. We investigated the effect different task-switching manipulations have on DMN activation in two studies with novel fMRI paradigms. In the first study, the paradigm manipulated visual discriminability, visuo-perceptual distance and sequential predictability during switching. Increased posterior cingulate/precuneus (PCC/PrCC) activity was evident during switching; critically, this was strongest when the occurrence of the switch was predictable. In the second study, we sought to replicate and further investigate this switch-related effect with a fully factorial design manipulating sequential, spatial and visual-feature predictability. Whole-brain analysis again identified a PCC/PrCC-centred cluster that was more active for sequentially predictable versus unpredictable switches, but not for the other predictability dimensions. We propose PCC/PrCC DMN subregions may play a prominent executive role in mapping the sequential structure of complex tasks.

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Arana-Oiarbide, G., Daws, R. E., Lorenz, R., Violante, I. R., Hampshire, A.. 2020-07-29. Preferential activation of the posterior Default-Mode Network with sequentially predictable task switches.. https://doi.org/10.1101/2020.07.29.223180

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