A hierarchy of timescales explains distinct effects of local inhibition of primary visual cortex and frontal eye fields.
Within the primate visual system, areas at lower levels of the cortical hierarchy process basic visual features, whereas those at higher levels, such as the frontal eye fields (FEF), are thought to modulate sensory processes via feedback connections. Despite these functional exchanges during perception, there is little shared activity between early and late visual regions at rest. How interactions emerge between regions encompassing distinct levels of the visual hierarchy remains unknown. Here we combined neuroimaging, non-invasive cortical stimulation and computational modelling to characterize changes in functional interactions across widespread neural networks before and after local inhibition of primary visual cortex or FEF. We found that stimulation of early visual cortex selectively increased feedforward interactions with FEF and extrastriate visual areas, whereas identical stimulation of the FEF decreased feedback interactions with early visual areas. Computational modelling suggests that these opposing effects reflect a fast-slow timescale hierarchy from sensory to association areas.
Queensland Brain Institute, The University of Queensland, Brisbane, Australia.|QIMR Berghofer Medical Research Institute, Brisbane, Australia.
Luca
0000-0003-3651-2676
L
Cocchi
Queensland Brain Institute, The University of Queensland, Brisbane, Australia.
Martin V
MV
Sale
QIMR Berghofer Medical Research Institute, Brisbane, Australia.
Leonardo
L
L Gollo
Queensland Brain Institute, The University of Queensland, Brisbane, Australia.
Peter T
PT
Bell
QIMR Berghofer Medical Research Institute, Brisbane, Australia.
Vinh T
VT
Nguyen
Melbourne Neuropsychiatry Centre, The University of Melbourne, Melbourne, Australia.
Andrew
A
Zalesky
QIMR Berghofer Medical Research Institute, Brisbane, Australia.|Metro North Mental Health Service, Brisbane, Australia.
Michael
M
Breakspear
Queensland Brain Institute, The University of Queensland, Brisbane, Australia.|School of Psychology, The University of Queensland, Brisbane, Australia.
Jason B
0000-0003-0929-9216
JB
Mattingley
D000328:Adult; D019295:Computational Biology; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008959:Models, Neurological; D009433:Neural Inhibition; D059906:Neuroimaging; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation; D014793:Visual Cortex / Q000502:physiology*; D055815:Young Adult
connectivity; cortical hierarchy; functional magnetic resonance imaging (fMRI); human; modelling; neuroscience; temporal hierarchy; transcranial magnetic stimulation (TMS)