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bioRxiv · 10.1101/482638

Bottom-up sensory processing can decrease activity and functional connectivity in the default mode like network in rats.

Hinz, R.·Peeters, L. M.·Shah, D.·Missault, S.·Belloy, M.·Vanreusel, V.·Malekzadeh, M.·Verhoye, M.·Van der Linden, A.·Keliris, G. A. A.
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Abstract

The default mode network is a large-scale brain network that is active during rest and internally focused states and deactivates as well as desynchronizes during externally oriented (top-down) attention demanding cognitive tasks. However, it is not sufficiently understood if unpredicted salient stimuli, able to trigger bottom-up attentional processes, could also result in similar reduction of activity and functional connectivity in the DMN. In this study, we investigated whether bottom-up sensory processing could influence the default mode like network (DMLN) in rats. DMLN activity was examined using block-design visual functional magnetic resonance imaging (fMRI) while its synchronization was investigated by comparing functional connectivity during a resting versus a continuously stimulated brain state by unpredicted light flashes. We demonstrated that activity in DMLN regions was decreased during visual stimulus blocks and increased during blanks. Furthermore, decreased inter-network functional connectivity between the DMLN and visual networks as well as decreased intra-network functional connectivity within the DMLN was observed during the continuous visual stimulation. These results suggest that triggering of bottom-up attention mechanisms in anesthetized rats can lead to a cascade similar to top-down orienting of attention in humans and is able to deactivate and desynchronize the DMLN.

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Hinz, R., Peeters, L. M., Shah, D., Missault, S., Belloy, M., Vanreusel, V., Malekzadeh, M., Verhoye, M., Van der Linden, A., Keliris, G. A. A.. 2018-11-29. Bottom-up sensory processing can decrease activity and functional connectivity in the default mode like network in rats.. https://doi.org/10.1101/482638

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