Psilocybin spent years as a maligned substance, better known for counterculture trips and moral panics. But its image has undergone a makeover in recent years as researchers around the world have studied its potential to ease depression, PTSD, anxiety, and addiction. Now, according to an incredible case study published in Frontiers in Neuroscience, it may have done something that sounds almost impossible: help a woman with late-stage Alzheimer’s disease speak for the first time in years.

The report is centered on a Japanese-American woman in her 80s whose Alzheimer’s had progressed for a decade. For around five years, she communicated mostly in single syllables. She needed constant care. She struggled to walk. She suffered from chronic urinary incontinence. And then, she was given a five-gram dose of mushrooms containing psilocybin.

Around 19 hours later, she woke up and started speaking in complete sentences, all the while recalling details from her life for nearly four hours, as if the years of being locked in her brain had made her antsy to speak again.

A Single Psilocybin Case Study Is Raising Big Questions About Alzheimer’s

Over the next few days, her caregivers reported that she started recognizing family members. She started to dress herself. She was walking more independently than before and even smiled and made eye contact. She regained bladder control. A second magic mushrooms session a month later provided even greater benefit, allowing her to emote more than she had previously and broadening her ability to engage socially.

The researchers stressed that this is not definitive evidence that psilocybin cures Alzheimer’s. Keep in mind, this is not a broad study that included numerous patients. It’s a case study of a single person. No brain scans or standardized cognitive tests were administered. It was all observational, based on the word of caregivers and family members. The researchers were certain that the brain damage caused by Alzheimer’s was still there.

And yet, this incredible case has raised a question that other research teams around the world will no doubt dive into: could some of the brain’s abilities be lying dormant inside people afflicted with Alzheimer’s, and can psilocybin help temporarily access them?

If that’s possible, how? One theory researchers have proposed is that psilocybin alters communication between brain networks, loosening activity patterns to allow surviving neural circuits to reconnect. Studies in animals have shown that psilocybin might promote neuroplasticity and reduce inflammation, so it’s not so far out of the realm of possibility.

Still, it’s way too early, and there isn’t nearly enough evidence to fully suggest that a single dose of psilocybin can jog an Alzheimer ’s-addled brain back into something that feels normal, even if it’s temporary. But, for families dealing with Alzheimer’s, this single case study might be a ray of hope.