Скачать или смотреть Talk: Reach-relevant somatosensory signals modulate the neural correlates of tactile suppression

Speaker: Belkis Ezgi Arikan, Justus-Liebig University Giessen
Title: Reach-relevant somatosensory signals modulate the neural correlates of tactile suppression
Emcee: Amita Kapoor
Backend host: Sophia Batchelor
Details: https://neuromatch.io/abstract?submis...
Lab website: https://www.uni-giessen.de/faculties/...
Paper link: https://doi.org/10.1167/19.14.4
Twitter:   / ezgibelkis  
Presented during Neuromatch Conference 3.0, Oct 26-30, 2020.

Summary: Tactile signals arising from goal-directed movements are typically suppressed. This results mainly from an internal model predicting sensory consequences of the movement, and attenuating those feedback signals matching the predictions. Feedback signals are, however, important to successfully control goal-directed movements requiring a flexible modulation of these signals. Despite behavioral evidence supporting such modulations of tactile suppression, the neural implementation of this modulation is not clear. Here, we investigated the neural correlates of tactile suppression during reaching movements targeted either to a static finger (somatosensory reach) or to a touchscreen (external reach). In the latter case, reach-relevant signals arose only from the moving hand, while in the former case additional feedback signals from the target hand were available. To probe tactile suppression, participants received brief vibrotactile stimuli to the moving finger prior to reach. Somatosensory and external reaches resulted in tactile suppression compared to resting (baseline), with stronger suppression during somatosensory than external reaches, as expected. At the neural level, BOLD activation associated with suppression was modulated by the reach goal: processing of probes during somatosensory reaching led to distinct BOLD deactivations in fronto-parietal regions compared to baseline and external reaching. These deactivations were more pronounced during somatosensory than external reaching in regions linked with somatosensory processing (postcentral gyrus, anterior insula), and sensorimotor prediction and integration (supplementary motor area, supramarginal gyrus). Our results suggest modulation of movement-related somatosensory signals in regions associated with predictive and feedback processing.