Experimental Brain Implant Automatically Relieves Pain

By Pat Anson, PNN Editor

An experimental brain implant that automatically detects and relieves pain in laboratory animals has the potential to be adapted for human use, according to researchers at NYU Grossman School of Medicine. The computerized device is the first of its kind to target both acute and chronic pain, and may also be effective in treating anxiety, depression, panic attacks and other brain-based disorders.

“Our findings show that this implant offers an effective strategy for pain therapy, even in cases where symptoms are traditionally difficult to pinpoint or manage,” said senior author Jing Wang, MD, an Associate Professor of Anesthesiology at NYU Langone Health.

The technology, known as a closed-loop brain-machine interface, detects brain activity in the anterior cingulate cortex, a region of the brain that is critical for pain processing. A computer linked to the device identifies pain signals in real-time, triggering a therapeutic stimulation of another region of the brain, the prefrontal cortex, to ease pain sensations.  

Wang and his colleagues installed the tiny electrodes in the brains of dozens of rats and then exposed them to carefully measured amounts of pain. The animals were closely monitored to see how quickly they moved away from a source of acute pain.

The study findings, published in the journal Nature Biomedical Engineering, showed that rats withdrew their paws 40 percent more slowly from the pain source when the device was turn on. In addition, animals in acute or chronic pain spent about two-thirds more time in a chamber where the device was turned on than in another chamber where it was not.

Researchers say the implant accurately detected pain up to 80 percent of the time. Since the device is only activated in the presence of pain, it lessens the risk of overuse, tolerance and addiction.

“Our results demonstrate that this device may help researchers better understand how pain works in the brain,” says lead investigator Qiaosheng Zhang, PhD, a doctoral fellow in the Department of Anesthesiology, Perioperative Care and Pain at NYU Langone. “Moreover, it may allow us to find non-drug therapies for other neuropsychiatric disorders, such as anxiety, depression, and post-traumatic stress.”

Zhang says the implant’s pain-detection properties could be improved by installing electrodes in other regions of the brain besides the anterior cingulate cortex. He cautions, however, that the technology is not yet suitable for use in people. Researchers are investigating whether less-invasive forms of the implant can be adapted for human use.

Brain implants – also known as deep brain stimulators -- are currently used to prevent seizures and tremors in people with Parkinson’s disease and epilepsy.