In a recent case report, they describe how a single dose of the drug zolpidem—more familiarly known by the brand name Ambien—can temporarily restore the man’s ability to talk and walk.

When he was given repeat doses of zolpidem throughout the day, the periods of normalcy grew more short-lasting each time, until the drug stopped working at all and even had a sedative effect on him.

Despite the elusiveness of a long-term cure for the man’s condition, his doctors still wanted to understand exactly how zolpidem was capable of causing such an amazing, if brief, turnaround.

So they studied his brain, via EEG and MRI, before and after he took the drug.

One possible future step, the authors speculated, is to use existing therapies like deep brain stimulation to balance out the brain’s overactivity for longer periods of time than zolpidem is capable of doing.