Viewers of 1970s sitcoms remember that actress who played Elaine on the TV series Taxi, but they might not recall her name. Actress Marilu Henner’s memory allows her to remember every single episode she starred in from start to finish, thanks to a rare condition called Highly Superior Auto-Biographical Memory (H-SAM for short).

Marilu Henner

In fact Marilu Henner remembers everything. She remembers every detail of her life, what she was doing on a certain day two years ago, what she ate for breakfast 6 years ago, who won best supporting actress at the Oscars every year she has watched, and well, everything else. Her long-term memory recall condition is scientifically confirmed by neurologists in only 24 people in the United States.

Her instant recall ability is known as H-SAM, which is shorthand for Highly Superior Auto-Biographical Memory. Just try to remember that one! When is was first identified in 2006 in scientific journals, it was originally called called hyperthymesia.

Those gifted with the ability are able to catalog their memories like a file cabinet, with every detail sorted properly for retrieval anytime they want instant recall. You can read about the characteristics of people like Marilu with this memory ability here.

You can challenge Marilu Henner with any date in her life, and she is likely to explain everything that happened from morning until night, no matter how trivial the detail. That can have drawbacks. Just imagine remembering every minute of the day that you spent with Danny DeVito, who played the super annoying character role of Louie De Palma in Taxi.

Marilu Henner’s H-SAM is quite different than having a photographic memory. People blessed with photographic memories are able to rapidly memorize a string of numbers, for example, by looking at it just once and reciting it immediately afterward. Such an ability is incredibly useful in card games like poker and bridge.

But Marilu’s short-term memory is no better than anyone else. What she has over you is the envy of every senior citizen, which is the ability to recall details from her long-term memory. You can read about her rare condition here and listen to her discuss it on camera in the video below.

To me she has a far more useful skill than counting cards. I’ve imagined growing old and not remember the first time my children laughed, their first steps, watching them play baseball, and even their eventual college graduation and wedding days. I’m so worried about my own memory that I capture way too many precious moments on video tape just to be sure I have them later in life.

With H-SAM, Marilu Henner’s memory will never let her down. She will always have those precious moments to relive anytime she likes. What a wonderful ability is Highly Superior Auto-Biographical Memory which only a few lucky people possess.