Researchers Find Out How Soft Sounds Ease Pain
Patients need to numb the pain to help them get through operations or the healing process. Professionals have been analyzing various methods on how to achieve it. Apparently, music has always been the answer to ease pain — an art good for both mind and body. A study was published in 1960 by a group of dentists regarding the use of music during operations. Surprisingly, music was able to lessen the pain — patients did not even ask for nitrous oxide or local anesthesia.
The dentist who led the study was from Boston and was named Wallace J. Gardner. According to his reports, he handed headphones to his patients and a small volume control box before the operation. Gardner and other dentists all over the country claimed that they performed dental procedures on 5000 patients with music and noise as pain relievers. Also, 90% of those operations did not use any anesthetic. Those medical providers have tested various pieces, from the works of Mozart to Michael Bolton.
Six decades after Gardner’s hypothesis, scientists gathered sufficient data to answer how sound can make the pain disappear. Yuanyuan Liu, a neurobiologist at the U.S. National Institute of Dental and Craniofacial Research, and his colleagues observed how music numbs pain in mice. The team played Bach’s Réjouissance for 20 minutes to the mice at 50 or 60 decibels in a room with a background noise set at 45 decibels. Using mice in the study was quite challenging as there’s uncertainty about how animals discern music.
Scientists exposed the mice to three types of music — symphonic music, unpleasant remixes of Bach’s symphony, and white noise. Those types of music were all effective and altered pain tolerance, more so when played at 50 decibels. To test the mice’s sensitivity to pain, they injected the paws with a painful solution and jabbed them with thin filaments at different pressures. They could determine the mice’s reaction to pain if they flinched, licked, or pulled their paws back. The experiment was done several times while observing a red fluorescent dye injected into the mice’s auditory cortex — part of the brain that processes sound.
Signals were found in particular regions of the thalamus — implying a link between those regions and the auditory cortex. Furthermore, the team implanted tiny electrodes into the mice’s brains which revealed that soft sounds lessen activity in the auditory cortex. They artificially blocked the link between the auditory context and the thalamus by targeting signals in certain neurons. The numbing effect lasted for two days after being exposed to sounds. For additional data, the team will be focusing on why low sound over background noise is the sweet spot of the process. As the study progresses, there will be more evidence that music can be medically used as an analgesic during operations.
Clifford Woolf, a neurobiologist at Harvard University, commented on the study, stating, “That now needs to be tested in humans. Many would have anticipated you need to listen to Mozart to get pain relief, but maybe all we need to do is give patients a tiny level of buzzing noise.”
Lastly, Zhi Zhang, a neurobiologist on the research team from the University of Science and Technology of China, sees the method as a way to decrease the pain in mice during experiments. It would be a remarkable way to test hypotheses without confounding the results, and it would decrease cruelty to animals.
