A new technique could relieve pain for individuals with various chronic and neurological conditions.
Researchers have found that electrical stimulation of the body combined with sound activates the brain’s somatosensory or “tactile” cortex, increasing the potential for using the technique to treat chronic pain and other sensory disorders. The non-invasive technique was tested on animals and the team is planning clinical trials on humans in the near future.
A University of Minnesota Twin Cities-led team conducted the study. The paper was published recently in the Journal of Neural Engineering, a highly regarded, peer-reviewed scientific journal for the interdisciplinary field of neural engineering.
During the experiments, the scientists played broadband sound while electrically stimulating different parts of the body in guinea pigs. They discovered that the combination of the two activated neurons in the brain’s somatosensory cortex. This is the area that is responsible for touch and pain sensations throughout the body.
In their experiments, the researchers used needle stimulation. However, similar results could be achieved using electrical stimulation devices, such as transcutaneous electrical nerve stimulation (TENS) units. These are widely available for anyone to buy at pharmacies and other stores. The scientists hope that their results will lead to a therapy for chronic pain that’s safer and more accessible than drug treatments.
“Chronic pain is a huge issue for a lot of people, and for most, it’s not sufficiently treatable,” said Cory Gloeckner, lead author on the paper, a 2017 Ph.D. alumnus of the University of Minnesota Twin Cities Department of Biomedical Engineering, and an assistant professor at John Carroll University. “Right now, one of the ways that we try to treat pain is opioids, and we all know that doesn’t work out well for many people. This, on the other hand, is a non-invasive, simple application. It’s not some expensive medical device that you have to buy in order to treat your pain. It’s something that we think would be available to pretty much anyone because of its low cost and simplicity.”
The research team plans to continue investigating this “multimodal” approach to treating different neurological conditions. Perhaps in the future, they can integrate music therapy to see how they can further modify the somatosensory cortex.
“A lot of people have been using acupuncture or electrical stimulation—non-invasive or invasive—to try to alter brain activity for pain,” said Hubert Lim, senior author on the paper and a professor in the University of Minnesota Twin Cities Department of Biomedical Engineering and Department of Otolaryngology. “Our research shows that when you combine this with sound, the brain lights up even more.”
Lim said this opens up a whole new field of using this bimodal and multimodal stimulation for treating diseases.
“It’s odd to think about using sound to treat pain, but if you think about what institutes like the University of Minnesota’s Center for Spirituality and Healing or the NIH’s National Center for Complementary and Integrative Health are doing, they’re looking at music therapy and combining other modalities with the traditional methods to be able to enhance healing of these types of conditions,” Lim said. “This research gives us a new, structured framework for doing that moving forward.”
Reference: “Topographic and widespread auditory modulation of the somatosensory cortex: potential for bimodal sound and body stimulation for pain treatment” by Cory D Gloeckner, Jian C Nocon and Hubert H Lim, 23 June 2022, Journal of Neural Engineering.
The research was funded by the National Science Foundation, the Lions Hearing Foundation, the University of Minnesota Interdisciplinary Fellowship, and University of Minnesota Lab Startup Funds.
In addition to Gloeckner and Lim, the research team included University of Minnesota Twin Cities Department of Biomedical Engineering alumnus Jian Nocon (B.S. BME ‘17).