The final, formatted version of the article will be published soon.
ORIGINAL RESEARCH article
Front. Hum. Neurosci.
Sec. Sensory Neuroscience
Volume 18 - 2024 |
doi: 10.3389/fnhum.2024.1429843
Effect of Touch on Proprioception: Non-Invasive Trigeminal Nerve Stimulation Suggests General Arousal Rather Than Tactile-Proprioceptive Integration
Provisionally accepted- Arizona State University, Tempe, Arizona, United States
Proprioceptive error of estimated fingertip position in two-dimensional space is reduced with the addition of tactile stimulation applied at the fingertip. Tactile input does not disrupt the participants’ estimation strategy, as the individual error vector maps maintain their overall structure. This relationship suggests integration of proprioception and tactile information improves proprioceptive estimation, which can also be improved with trained mental focus and attention. Task attention and arousal are physiologically regulated by the reticular activating system (RAS), a brainstem circuit including the locus coeruleus (LC). There is direct and indirect evidence that these structures can be modulated by non-invasive trigeminal nerve stimulation (nTNS), providing an opportunity to examine nTNS effect on the integrative relationship of proprioceptive and tactile information. Fifteen right-handed participants performed a simple right-handed proprioceptive estimation task with tactile feedback (touch) and no tactile (hover) feedback. Participants repeated the task after nTNS administration. Stimulation was delivered for 10 minutes, and stimulation parameters were 3000 Hz, 50 µs pulse width, with a mean of 7mA. Error maps across the workspace are generated using polynomial models of the participants’ target responses. Error maps did not demonstrate significant vector direction changes between conditions for any participant, indicating that nTNS does not disrupt spatial proprioception estimation strategies. A linear mixed model regression with nTNS epoch, tactile condition, and the interaction as factors demonstrated that nTNS reduced proprioceptive error under the hover condition only. We argue that nTNS does not disrupt spatial proprioceptive error maps but can improve proprioceptive estimation in the absence of tactile feedback. However, we observe no evidence that nTNS enhances tactile-proprioceptive integration as the touch condition does not exhibit significantly reduced error after nTNS.
Keywords: Proprioception1, Trigeminal Nerve Stimulation4, Cranial Nerve Stimulation5, Tactile-Propriopceptive Integration, Neuromodulation
Received: 08 May 2024; Accepted: 09 Sep 2024.
Copyright: © 2024 Tanner, Orthlieb and Helms Tillery. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
Justin Tanner, Arizona State University, Tempe, 85281, Arizona, United States
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.