The effects of pain on motor learning
Date
2021
Authors
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Publisher
University of Delaware
Abstract
Learning new ways to move the body is an incredibly important part of physical rehabilitation and there are many factors that have the potential to influence how well new movements are acquired or remembered. Pain and cognition are two such factors, however it is currently not well understood how either interact with motor learning processes. Pain is a multimodal stimulus that is processed throughout the brain in a widespread network that overlaps with regions thought to be critical for motor learning. This provides the neural substrate for both acute and chronic pain to interact with motor learning, though it is currently not clear if they actually do. Further, it is becoming appreciated that cognition plays an important role in at least some types of motor learning and that chronic pain is commonly linked to reduced cognitive performance. Therefore, cognitive deficits associated with chronic pain conditions may also impact motor learning processes, though, to date, these interrelationships have not been explored. The overall purpose of this dissertation was to address these factors with a comprehensive examination of the effects of pain on motor learning. ☐ In Aim 1, we showed that experiencing acute pain during motor learning reduced how well a newly learned pattern was remembered, and that the amount of forgetting was associated with the intensity of pain experienced by the participants. This finding is significant because it indicates that pain felt during motor learning-based physical rehabilitation interventions could interfere with retention of those newly learned motor behaviors. Future work should assess whether taking measures to reduce pain can lessen this impact. ☐ In Aim 2, we showed that although individuals with chronic low back pain (CLBP) were able to at least partially learn a new walking pattern, they did so in a different way than non-painful control participants. Individuals with CLBP had overall greater task errors during learning, and final task error for these individuals was correlated with pain sensitivity. A better understanding of these learning differences and the mechanisms behind them may be critical to optimizing motor learning-based interventions for individuals with chronic pain. ☐ Finally, in Aim 3, we showed that pain sensitivity was related to working memory in individuals with CLBP, and that pain sensitivity may mediate the relationship between working memory and motor learning. This finding is significant because it is the first to demonstrate that chronic pain, cognition and motor learning are interrelated, and that screening for increased sensitivity or decreased cognition may help identify individuals with chronic pain who are at risk for altered or poor motor learning. ☐ Overall, this novel body of work demonstrates that pain, though ubiquitous in physical rehabilitation, may be deleterious for motor learning outcomes, and highlights that improving our understanding of the specific effects of acute and chronic pain is critical for establishing best clinical practices for patients with pain.
Description
Keywords
Chronic Pain, Cutaneous Pain, Explicit, Gait, Motor Learning, Walking