Consider the possibility of alleviating pain without invasive procedures, targeting a specific brain region where pain signals are processed. A recent study led by Wynn Legon, PhD, an assistant professor at the Fralin Biomedical Research Institute at Virginia Tech’s College of Science, suggests this may be attainable.

Published in the journal PAIN, the study indicates that low-intensity focused ultrasound waves directed at the insula, a deep brain region, can reduce pain perception and associated effects such as heart rate fluctuations.

“This is a proof-of-principle study,” Legon says. “Can we get the focused ultrasound energy to that part of the brain, and does it do anything? Does it change the body’s reaction to a painful stimulus to reduce your perception of pain?”

Focused ultrasound, like the technology used for fetal imaging, directs a precise beam of sound waves to a small target. When used at high intensity, it can remove tissue, but at low intensity, it has milder, temporary effects, like modifying nerve cell electrical activity.

Neuroscientists have long studied how non-surgical techniques, such as transcranial magnetic stimulation, might be used to treat depression and other issues. Legon’s study, however, is the first to target the insula and show that focused ultrasound can reach deep into the brain to ease pain.

The study included 23 healthy individuals. Pain was induced on their hand backs using heat. Simultaneously, they wore a device guided by MRI to deliver focused ultrasound waves to a specific brain area. Participants rated their pain on a scale from zero to nine. The researchers also tracked heart rate and its irregularity (heart rate variability) to understand how brain-targeted ultrasound impacted their response to pain.

Participants reported an average reduction in pain of three-fourths of a point. “That might seem like a small amount, but once you get to a full point, it verges on being clinically meaningful,” says Legon. ”It could make a significant difference in quality of life, or being able to manage chronic pain with over-the-counter medicines instead of prescription opioids.”

The study also found the ultrasound application reduced physical responses to the stress of pain—heart rate and heart rate variability, which are associated with better overall health. “Your heart is not a metronome. The time between your heart beats is irregular, and that’s a good thing,” Legon says. “Increasing the body’s ability to deal with and respond to pain may be an important means of reducing disease burden.”

The effect of focused ultrasound on those factors suggests a future direction for the Legon lab’s research—to explore the heart-brain axis, or how the heart and brain influence each other, and whether pain can be mitigated by reducing its cardiovascular stress effects.