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WAUKESHA, Wis. — “We used the Colin 27.”

“What’s a Colin 27?”

“It’s a brain atlas standard.”


“OK, but who is that?”



“Colin 27.”

“I dunno. Probably a guy named Colin.”

And that’s how I first met Colin Holmes — or, rather, his famous brain.

Kareem Zaghloul, of the National Institutes of Health, had put it up on a projector screen during a visit to his lab last year. Colin 27, he said, was great for helping to map out epileptic hot spots in the brains of his patients.

And it’s not just Zaghloul’s patients.

Holmes has the most notable brain in science. Also known as “Average Colin,” it has appeared in over 800 scientific papers — and more citations come in almost every week. It’s been featured in studies of stroke, HIV, Alzheimer’s, and even the brain benefits of eating fish. Holmes also noted that over 1,000 labs around the world use his brain in some way.

But while Colin 27 is known widely throughout neuroscience, Holmes’s personal identity has been a mystery to most scientists.

“I’m not a promotional person,” he said in a recent interview.

It has been more than 20 years since Holmes, now 52, laid in stiff repose, undergoing more MRI scans than most of us will have in our lifetimes. At the time, he was 28 and a graduate student at the Montreal Neurological Institute. The hours of voluntary work were all in the name of making a better image of a living brain — his own.

Today, you could get a high-quality MRI in about 10 minutes. But back then, it was real work. If Holmes breathed too deeply: wrecked scan. If he sneezed: wrecked scan. If he moved his eyes: wrecked scan. He said he still has a sore spot on the back of his head — an occupational safety science hazard, perhaps.

In the end, he was able to combine 27 10-minute scans to make one high-quality average — hence Colin 27.

Holmes is now a director of product management for GE in Waukesha, and often bumps into his brain while traveling for work.

“I’ve seen it all across the United States. I’ve seen it in Japan, Korea, all over Europe,” he said.

Holmes has never received royalties for the use of his brain image, and had no idea it would be so widely applied. He said he’s just glad his brain has been useful to science.

“It still surprises me that every other day I get an announcement of someone citing that work, even though it’s from 1998.”

In June, Holmes recreated his original scan, just to see what has changed in his skull after two decades. He said he was hoping not to see any “massive gaps” or “shrinkage” in his cortex.

“I’m still pretty young, we’re hoping,” he said.

About an hour later, he was checking back in on Colin 27. His reaction? Relieved.

“I think I’ve got some time left.”