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Memory Memory Everything feels so fleeting these days. This week we're stepping back to explore all things memory in technology, science, and entertainment. Prev Next View All

The ability to remember every moment of your life sounds like an amazing proposition, but for the very few people who actually have this ability, it comes at a cost.




Known as Highly Superior Autobiographical Memory (HSAM), or hyperthymesia, the condition—such that it is—was first chronicled by University of California-Irvine neurobiologist James McGaugh in 2006. In his seminal Neurocase study, McGaugh described “AJ,” a 42-year-old woman “whose remembering dominates her life.”



Not to be confused with photographic or eidetic memory, or professionals who use sophisticated mnemonic recall strategies, HSAM describes individuals who spend an “abnormally large amount of time” thinking about their past, and who have an “extraordinary capacity to recall specific events from their personal past,” as McGaugh first defined the condition. But as McGaugh noted in his study, AJ’s superhuman recall abilities have their drawbacks.


“Give me the day and I see it,” she told the researchers. “I go back to the day and I just see the day and what I was doing.”

AJ compared it to a split-screen television, where she’d be talking to someone and suddenly a vivid scene would pop into her head.

“Like we’re sitting here talking and I’m talking to you and in my head I’m thinking about something that happened to me...[on]...December 17, 1982, it was a Friday, I started to work at [a store],” she said. “It’s all about dates.”

Indeed, while observing AJ, McGaugh and his colleagues marvelled at her ability to recall the details of every Easter for the past 24 years (which were corroborated with her diaries), and she gave the correct dates for completely trivial events, such as the date on which the Dallas episode “Who Shot J.R.?” first aired.


At the same time, AJ described her recall abilities as “exhausting,” saying her memory has “ruled her life.” She said she thinks about the past “all the time,” and that it’s like a “running movie that never stops.” Negative memories are particularly problematic for AJ, saying “I only have to experience something one time and I can be totally scarred by it... I can’t let go of things because of my memory, it’s part of me.”

After McGaugh and his colleagues published the paper, other HSAMs have stepped forward, including artist Nima Veiseh, who can recall his personal experiences for the past 17 years. Like AJ, Veiseh can recall absurdly insignificant details, such as the clothes he was wearing on a particular day, or which side of the train he was sitting on while commuting to work. “My memory is like a library of VHS tapes, walk-throughs of every day of my life from waking to sleeping, “ he told the BBC in 2016. Similarly, Marquette University graduate Markie Pasternak, who was assessed as having HSAM in her early 20s, can recall what she did, who she spoke to, what she ate, and even how she felt, on any date going back to her childhood. In total, fewer than 100 confirmed cases of HSAM have appeared worldwide over the past 10 years, but the number is steadily growing as more people become aware of it.


Scientists aren’t entirely sure what’s going on neurologically or psychologically in HSAMs, but clues are beginning to emerge.

“One very interesting thing is that it is selective for personal, autobiographical memory—the events of your day—and not other kinds of memory,” Craig Stark, a neurobiologist and expert on HSAM from the University of California-Irvine, told Gizmodo. “In addition, we know that they’re not better at learning this information. They just forget it much, much more slowly. Their memory for yesterday isn’t better than yours or mine. But, they may remember the events of a day from a decade ago the way we might remember last week.”


Research done by Stark and his colleagues shows that neurotypical people are just as good as people with HSAM at recalling personal information after one week. After longer durations of time, such as one month or a year, HSAMs retain the ability to recall information with exquisite clarity, while the neurotypical people (the control group) most certainly cannot.

Lawrence Patihis, a psychologist at the University of Southern Mississippi, says there have been a few behavioral and brain scan studies done on people with HSAM by McGaugh, Stark, and UC-Irvine data scientist and neurobiologist Aurora Leport, among others.


“They have found that individuals with hyperthymesia have obsessive tendencies more so than people without superior memory, and they have found small differences in the size of areas of the brain involved in memory, as well as functional connectivity differences in circuits thought to involve memory,” Patihis told Gizmodo. “Their work and the work we did together found people with hyperthymesia have pronounced memory advantages just in one domain: autobiographical memory with dates attached. This work confirmed they do not have photographic memory, that they reconstruct memories with the potential for error as we all do, and they are fairly average on other memory tasks.”

Patihis said HSAM has also been correlated with personality traits such as being prone to fantasy, having an overactive imagination, and becoming obsessed with new information. Combined with their obsessive tendencies, said Patihis, these personality traits likely play a role in the consolidation of memory.


“At an early age, HSAMs also realized they were different and have certainly had to come up with coping strategies to deal with the fact that they will remember not only positive interactions, but every negative one as well,” said Stark. “There seem to be higher than typical rates of OCD-like behaviors in the population, but we need to keep in mind that the people with HSAM that we have studied are highly functional, successful members of society (there may be people with HSAM who are less functional and do not contact us, of course).”



During the original 2006 study, AJ told McGaugh: “I don’t think I would never want to have this, but it’s a burden.” The comment speaks to the double-edged nature of the condition. While the painful flashbacks and unwanted memories are most certainly a problem, HSAM also offers some benefits, as David Robson reported in his 2016 BBC Future article:

The people with HSAM I’ve interviewed would certainly agree that it can be a mixed blessing. On the plus side, it allows you to relive the most transformative and enriching experiences. [Nima] Veiseh, for instance, is something of a polymath. He travelled a lot in his youth to compete in international taekwondo competitions, but in his spare time, he visited the local art galleries, and perhaps because his love of art is entwined with his identity, the paintings are now lodged deep in his autobiographical memories. “Imagine being able to remember every painting, on every wall, in every gallery space, between nearly 40 countries,” he says. “That’s a big education in art by itself.” With this encyclopaedic knowledge of the history of art, he has since become a professional painter, under the moniker “Enigma of Newyork”. Similarly, his memory may have also aided his other career as a doctoral researcher in design and technology, he thinks, by helping him to absorb a vast body of knowledge.


Patihis agrees, saying it’s not consistently the case that all people with HSAM have the same burdens as described by AJ. Most seem to be highly organized, though a bit obsessive, he says.

These accounts notwithstanding, there does appear to be some value in forgetting, whether it be autobiographical memory or the flood of information that pours into our brain on a daily basis. The human brain, it has been argued, must forget unimportant information in order to remain efficient.


In 2014, researchers from the University of Basel in Switzerland argued that the brain is actively, rather than passively, working to rid itself of superfluous information. A “plastic nervous system,” the researchers argued, “requires the ability not only to acquire and store but also to forget.” In terms of the mechanics involved in this process, the researchers pinpointed a molecule, called the Musashi protein, which appeared to contribute to time-dependent memory loss in nematode worms . Their research suggests memory loss is an acquired trait, and it’s a deliberate, evolved physiological process —i n nematode worms, at least.

Similarly, Stark says we need to remember, ahem, that our memory is designed to forget irrelevant details.


“We extract knowledge and wisdom by seeing links and common structure across events, rarely involving specific episodic details,” he told Gizmodo.

Stark pointed to the 1942 short story, “Funes the Memorious” by Jorge Luis Borges, in which the main character, after falling off his horse and hitting his head, was suddenly able to remember everything. Funes soon became debilitated by his newly acquired condition, demonstrating the perils of extreme recollection.


But for those with HSAM, it’s not a perfect memory. Rather, “it’s the sound-bite or short diary entry for the day that is remembered,” said Stark. “It’s like your memory for a week ago, not your memory of the last few minutes.”

HSAM or not, we’re all influenced by our past. We rely on our memories to form our personal narrative and build our identity. But for some people, their life story is more an opus than a novel.