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Abstract Processing sensory information, generating perceptions, and shaping behavior engages neural networks in brain areas with highly varied representations, ranging from unimodal sensory cortices to higher-order association areas. In early development, these areas share a common distributed and modular functional organization, but it is not known whether this undergoes a common developmental trajectory, or whether such organization persists only in some brain areas. Here, we examine the development of network organization across diverse cortical regions in ferrets using in vivo wide field calcium imaging of spontaneous activity. In both primary sensory (visual, auditory, and somatosensory) and higher order association (prefrontal and posterior parietal) areas, spontaneous activity remained significantly modular with pronounced millimeter-scale correlations over a 3-wk period spanning eye opening and the transition to externally-driven sensory activity. Over this period, cortical areas exhibited a roughly similar set of developmental changes, along with area-specific differences. Modularity and long-range correlation strength generally decreased with age, along with increases in the dimensionality of activity, although these effects were not uniform across all brain areas. These results indicate an interplay of area-specific factors with a conserved developmental program that maintains modular functional networks, suggesting modular organization may be involved in functional representations in diverse brain areas.
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Organization of the human cerebral cortex estimated within individuals: networks, global topography, and function
The organization of cerebral networks was estimated within individuals with intensive, repeat sampling of fMRI data. A hierarchical organization emerged in each individual that delineated first-, second-, and third-order cortical networks. Regions of distinct third-order association networks consistently exhibited side-by-side juxtapositions that repeated across multiple cortical zones, with clear and robust functional specialization among the embedded regions.
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- Award ID(s):
- 2024462
- PAR ID:
- 10540129
- Publisher / Repository:
- American Physiological Society
- Date Published:
- Journal Name:
- Journal of Neurophysiology
- Volume:
- 131
- Issue:
- 6
- ISSN:
- 0022-3077
- Page Range / eLocation ID:
- 1014 to 1082
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1152/jn.00308.2023
