1. Suppressive recurrent and feedback computations for adaptive processing in the human brain
- Author
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Zamboni, E, Kemper, VG, Goncalves, NR, Jia, K, Bell, SJ, Karlaftis, VM, Giorgio, JJ, Rideaux, R, Goebel, R, and Kourtzi, Z
- Subjects
genetic structures - Abstract
Humans and animals are known to adapt to the statistics of the environment by reducing brain responses to repetitive sensory information. Despite the importance of this rapid form of brain plasticity for efficient information processing, the fine-scale circuits that support this adaptive processing in the human brain remain largely unknown. Here, we capitalize on the sub-millimetre resolution afforded by ultra-high field (UHF) imaging to examine BOLD-fMRI signals across cortical depth and discern competing hypotheses about the brain mechanisms (feedforward vs. feedback) that mediate visual adaptation. Combining UHF imaging with a visual adaptation paradigm comprising repeated presentation of gratings at the same orientation, we provide evidence for the fine-scale human brain circuits that mediate adaptive visual processing. We demonstrate that visual adaptation is implemented by suppressive local recurrent processing within visual cortex, as indicated by stronger BOLD decrease in superficial than middle and deeper layers. Further, functional connectivity analysis shows dissociable connectivity mechanisms for adaptive processing: feedforward connectivity within the visual cortex, while feedback connectivity from posterior parietal to visual cortex, reflecting top-down influences (i.e. expectation for repeated stimuli) on visual processing. Thus, our findings provide evidence for a circuit of local recurrent and feedback interactions that mediate rapid brain plasticity for adaptive information processing.
- Published
- 2020
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