TY - JOUR
T1 - Bottom-up sensory processing can induce negative BOLD responses and reduce functional connectivity in nodes of the default mode-like network in rats
AU - Hinz, Rukun
AU - Peeters, Lore M.
AU - Shah, Disha
AU - Missault, Stephan
AU - Belloy, Michaël
AU - Vanreusel, Verdi
AU - Malekzadeh, Meriam
AU - Verhoye, Marleen
AU - Van der Linden, Annemie
AU - Keliris, Georgios A.
N1 - Publisher Copyright:
© 2019 Elsevier Inc.
PY - 2019/8/15
Y1 - 2019/8/15
N2 - 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 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 the BOLD response 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 sedated rats can lead to a cascade similar to top-down orienting of attention in humans and is able to deactivate and desynchronize the DMLN.
AB - 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 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 the BOLD response 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 sedated rats can lead to a cascade similar to top-down orienting of attention in humans and is able to deactivate and desynchronize the DMLN.
KW - Default mode network
KW - Functional connectivity
KW - Rats
KW - Resting-state functional MRI
KW - Visual stimulation
UR - http://www.scopus.com/inward/record.url?scp=85064940674&partnerID=8YFLogxK
U2 - 10.1016/j.neuroimage.2019.04.065
DO - 10.1016/j.neuroimage.2019.04.065
M3 - Article
C2 - 31029872
AN - SCOPUS:85064940674
SN - 1053-8119
VL - 197
SP - 167
EP - 176
JO - NeuroImage
JF - NeuroImage
ER -