In an initial trial, patients who suffer from chronic nerve pain got relief from an interactive game that trained them to alter their own brainwaves. The promising results could lead to a new generation of drug-free treatments, according to the study.

A research team led by psychologists from the University of New South Wales in Sydney, Australia developed PainWaive—a training system that teaches users to regulate abnormal brain activity that underlies nerve pain—as a potential in-home, non-invasive alternative to opioids. The results, published in The Journal of Pain in April, showed that three out of four participants saw significant reductions in pain five weeks after the last treatment.

The PainWaive system consists of an electroencephalogram (EEG) headset that records brain activity paired with an app that instructs patients on how to control their brainwaves through neurofeedback games, according to a UNSW statement. Four participants who suffer from corneal neuropathic pain—a condition that causes painful hypersensitivity of the eyes, face, or head—underwent 20 PainWaive sessions over the course of four weeks.

Doctors aren’t sure exactly what causes corneal neuropathic pain, and this condition rarely responds to current treatments, according to the researchers. But they hypothesized that altering brainwaves generally associated with nerve pain could provide relief.