In the early 2000s, Frankie Muniz was one of the most famous child actors in the world.
For six years, he was the star of the critically acclaimed family sitcom Malcolm in the Middle, earning a nomination for an Emmy for Outstanding Lead Actor in a Comedy Series at just 15 years old.
But for many years, it was believed that Muniz, now 36, didn't remember a single moment from the show.
Watch a clip from Frankie Muniz's interview on Steve-O's Wild Ride below. Post continues after video.
In October 2017, while Muniz was appearing on Dancing with the Stars, the show ran an episode with the theme 'Most Memorable Year'.
When asked to recall events from his childhood and adolescence, Muniz claimed that he has no memory of being on Malcolm in the Middle.
"I'm not actually sure how my memory loss started," he said.
"I have had nine concussions and I've had a fair amount of mini-strokes," he continued.
"I've never been to the doctor and been like, you know, 'Why don't I have a memory?' To be honest, I've never really talked about it.
"It makes me a little sad. Things pop back into my mind that I should have remembered."
Speaking to Entertainment Weekly after his appearance on Dancing with the Stars, Muniz said he had his first 'mini-stroke' (otherwise known as a transient ischemic attack - involving a temporary blockage in the brain) in 2012.
He was riding a motorbike and suddenly lost his peripheral vision, and when he returned home, he couldn't recognise his mum or girlfriend. When he went to the hospital, he was given no definitive answers.