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Title: Multisensory integration in the mouse cortical connectome using a network diffusion model
Author Summary Having a structural network representation of connectivity in the brain is instrumental in analyzing communication dynamics and neural information processing. In this work, we make steps towards understanding multisensory information flow and integration using a network diffusion approach. In particular, we model the flow of evoked activity, initiated by stimuli at primary sensory regions, using the asynchronous linear threshold (ALT) diffusion model. The ALT model captures how evoked activity that originates at a given region of the cortex “ripples through” other brain regions (referred to as an activation cascade). We apply the ALT model to the mouse connectome provided by the Allen Institute for Brain Science. A first result, using functional datasets based on voltage-sensitive dye (VSD) imaging, is that the ALT model, despite its simplicity, predicts the temporal ordering of each sensory activation cascade quite accurately. We further apply this model to study multisensory integration and find that a small number of brain regionsthe claustrum and the parietal temporal cortex being at the top of the listare involved in almost all cortical sensory streams. This suggests that the cortex relies on an hourglass architecture to first integrate and compress multisensory information from multiple sensory regions, before utilizing that lower dimensionality representation in higher level association regions and more complex cognitive tasks.  more » « less
Award ID(s):
1755871 1822553
PAR ID:
10208017
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Network Neuroscience
Volume:
4
Issue:
4
ISSN:
2472-1751
Page Range / eLocation ID:
1030 to 1054
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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