Open AccessEarly fMRI responses to somatosensory and optogenetic stimulation reflect neural information flow
Author(s) -
Won Beom Jung,
Geun Ho Im,
Haiyan Jiang,
SeongGi Kim
Publication year - 2021
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2023265118
Subject(s) - optogenetics , somatosensory system , neuroscience , stimulation , functional magnetic resonance imaging , cortex (anatomy) , local field potential , biological neural network , premovement neuronal activity , psychology , brain mapping , computer science
Significance fMRI has revolutionized how neuroscientists investigate human brain functions and networks. To further advance understanding of brain functions, identifying the direction of information flow, such as thalamocortical versus corticothalamic projections, is critical. Because the early hemodynamic response at microvessels near active neurons can be detected by ultrahigh field fMRI, we propose using the onset times of fMRI responses to discern the information flow. This approach was confirmed by observing the ultrahigh spatiotemporal resolution BOLD fMRI responses to bottom-up somatosensory stimulation and top-down optogenetic stimulation of the primary motor cortex in anesthetized mice. Because ultrahigh field MRI is increasingly available, ultrahigh spatiotemporal fMRI will significantly facilitate the investigation of functional circuits in humans.