The Role of the Brain in Chronic Pain
Professor Lorimer Mosely from the University of South Australia explores the connection between the brain and body in relation to the presence of pain. Throughout the video he examines the role the brain plays in chronic pain as well as how the brain adapts as the pain persists over time.
Initially, he describes the internal pathway of the moment a stimulus touches your body, moves up the spinal cord to the thalamus, and then how the brain identifies the stimulus. To do this, the brain calls on previous experiences with the stimulus, and selects the response accordingly.
Professor Mosely mentions a study about how two groups were touched with the same piece of metal, and one group was presented a red light when touched and the other group with a blue light. While controlling for temperature and pressure of the small piece of metal, the participants who were touched and saw a red light identified a painful experience, with some individuals rating the pain as an 8 out of 10. However, participants who were touched by the same small piece of metal and saw the blue light rated a low level of perceived pain. Professor Lorimer Mosely states that pain depends on the perceived stimulation level, not the actual stimulation level itself.
This suggests that pain is the output of the brain, meaning it does not exist until the brain says it does. To further this, pain does not exist in the individual tissues, but only in the brain itself. When pain persists, there is an increase in sensitivity, (ex: just seeing someone bend over and lift a heavy box will give you back pain) and a decrease in precision (pain starts to spread to other body parts). When pain persists over time it becomes classified as chronic. Professor Mosely suggests that chronic pain is real but no longer an accurate representation of damage to the body.
In individuals with limb-loss, nearly 80% have experienced pain, whether it be from the residual limb or phantom pain. Professor Mosely’s talk about the relationship between the mind and pain, creates a new perspective on managing pain in individuals with limb-loss.
Reference : https://www.ncbi.nlm.nih.gov/books/NBK448188/
Macy is a senior undergraduate student at the University of Delaware majoring in exercise science. She has an interest in the field of orthotics and prosthetics and currently works in the Delaware Limb Loss Studies Lab at the University of Delaware