HSAM Is The Incredibly Rare Condition Of Superhuman Memory

What were you doing on the morning of August 9th, 2002? If you're like most people, you haven't the faintest idea. If you're one of the rare people with highly superior autobiographical memory (HSAM), however, you'll probably remember almost everything about the day, right down to the way you felt. Scientists don't know what exactly gives people with HSAM this superpower, but they have some theories.

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A Blessing And A Curse

The first documented case of HSAM was published in 2006. It told the story of "AJ"—the pseudonym for Jill Price, who has since made her identity known—and described the peculiar way her memory works. The study quotes the email she first sent a researcher about her peculiar gift: "I can take a date, between 1974 and today, and tell you what day it falls on, what I was doing that day and if anything of great importance (i.e.: The Challenger Explosion, Tuesday, January 28, 1986) occurred on that day I can describe that to you as well...Whenever I see a date flash on the television (or anywhere else for that matter) I automatically go back to that day and remember where I was, what I was doing, what day it fell on and on and on and on and on. It is non-stop, uncontrollable and totally exhausting."

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Since then, a handful more people have come forward and—after careful testing—been identified as having HSAM. Even so, it's still vanishingly rare, affecting only around 60 people worldwide. Scientists are hard at work studying those people in hopes that uncovering the root of their power will also uncover the ways that the average human memory works.

What's Going On?

There are a few things that make people with HSAM different than the rest of us. Most seem to have obsessive behaviors, such as a tendency to collect, clean, or organize things to an unusual degree. This makes some sense—someone who "collects" and organizes their memories would have an easier time recalling them. But that doesn't explain it all. Brain scans show structural differences in the parts associated with autobiographical memory creation, and studies show that when you ask people with HSAM and control subjects to recall an event at the same time, the controls will forget after about a week whereas HSAM subjects will remember it for a decade or more.

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The more interesting thing about the condition is not their differences from other people, but their similarities. For example, just because they have amazing memory recall doesn't mean those memories are perfect: people with HSAM are just as susceptible to false memories as the rest of us. Likewise, people with HSAM recall their memories with the same systems everyone else does. The Guardian reports, "This also implies that the thing HSAM people are doing differently to the rest of us happens somewhere in between the encoding of a memory and its retrieval—in the space where consolidation into a long-term memory takes place." What that is is anybody's guess, but scientists are trying to find out.

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