By Linda Carroll, NBC News
While most of us have trouble remembering the details of even the most important days of our lives, college student Aurelien Hayman can recall every moment of his life, no matter how mundane.
Give him a year and a date and he can tell you what day of the week it was, what the weather was like - even what he ate for breakfast.
"I can just remember these sorts of things without even trying - and without them having any importance," Hayman told TODAY. "I just remember them."
Hayman is one of a small group of people who have extraordinary ability to recall specific details of events, even ordinary days, that happened years ago. TODAY has interviewed several of them over the years, including actress Marilu Henner, who stunned Meredith Vieira in an interview with the vivid recall of the last time they'd brushed past one another.
Though the phenomenon has only recently been identified, scientists have given this special kind of memory a name: Highly Superior Autobiographical Memory, or HSAM.
Because it's so new, there's been little research on the topic. But in July of this year a study of 11 people with HSAM was published in the journal Neurobiology of Learning and Memory.
Researchers from the University of California, Irvine, interviewed 11 people with HSAM and scanned their brains. And while the researchers did identify nine brain areas that seemed to be different in size and shape from those of volunteers with typical memories, what really caught the researchers' attention were the differences in behavior.
People with HSAM tend to obsess over events (even mundane ones) more than the average person. They ruminate over what happened during the day and organize everything in their minds over and over again.
In fact, they often report "habitually recalling their memories, a seemingly compulsive tendency," noted Aurora K.R. LePort and her colleagues. "Every night before bed one participant recalls what occurred on that day X number of years ago. Another recalls, while stuck in traffic, as many days as possible from a certain year."
Memory expert Dr. Gary Small believes we should study people like Hayman and Henner to help people who are losing their memory due to disease or old age.
"We are involved in memory training techniques to teach people to try to improve their memories - and of things that individuals with extraordinary biographical memory seem to do instinctively," said Small, director of the Longevity Center at the University of California, Los Angeles, and author of "The Alzheimer's Prevention Program: Keep Your Brain Healthy for the Rest of Your Life."
"I think that probably their brains are wired so that they can naturally do what we teach others to do to improve their memories: focusing attention, creating associations and giving those associations meaning."
While a perfect memory might seem like a gift, some people find it a real burden.
Jill Price, 46, wishes she couldn't remember everything quite so well. She is plagued by her inability to escape unhappy memories that are so detailed that they feel like they just happened.
"Thinking about something from 20 years ago that means absolutely nothing to me today, but still bothers me or still upsets me," Jill said. It's like yesterday. It really is."
But for Hayman and most of the people in the new study, HSAM is a gift.
"As a group they view their autobiographical memory ability as a positive attribute," LePort and her colleagues concluded.
Hayman himself only recently realized that his memory was out of the ordinary.
"Now that I know it's something special, I think I'll sort of value it more," he told TODAY.