March 15, 2001 -- Ever wonder why Dustin Hoffman's autistic
character in Rain Man could memorize every name and number in the phone
book, but thought that a candy bar and a car each cost 50 cents?
"Autistic individuals don't use context to enhance their
memory and learning the way most people do," David Beversdorf, MD, an
assistant professor of neurology at Ohio State University in Columbus, tells
WebMD. "Normal individuals use context to help categorize and remember new
By Gretchen Rubin
When our two daughters were little, they'd greet my husband and me with wild enthusiasm whenever we walked in the door, and they often cried miserably when we left. More recently, however, they had sometimes barely looked up from their games or homework or books when we walked in or out. It was a relief, in a way, but also a little sad. And too often, my husband and I didn't give warm greetings or farewells to the girls or to each other, either.
I had already made a long-standing...
Most people couldn't care less about the telephone book but can
remember the phone numbers of family, friends, and business associates because
this information means more in the context of daily life. And if you find
yourself with an extra 50 cents burning a hole in your pocket, you'll remember
that the price of a candy bar is within your reach, but the price of a shiny
new Ferrari is light years away.
Although autism severely limits social and work skills, which
depend heavily on cues taken from context and setting, it may actually improve
memory tasks not dependent on context, Beversdorf found in a study published
last year in Proceedings of the National Academy of Science.
People without autism asked to remember a list of words like
"thread," "pin," "eye," "sewing" -- and other
terms related to the word "needle" -- were more likely than autistic
people to assume that "needle" was on the list, even though this
"memory" was false.
With aging, more "false memory" errors pop up, which
Beversdorf suggests may represent a way our brain compensates for our failing
"If we can't keep track of picky details as we get older,
we use contextual cues to help us remember the gist of things, although the
specifics may be inaccurate," he says.
Even when you're young, your eyes and your mind may play tricks
on you. Eyewitnesses who think they remember a crime may identify the wrong
person from a lineup.
"We feel that we see and retain everything around us, much
as a video camera records all of the details, and that with the correct cues or
aids we could somehow recall everything we saw," says Daniel J. Simons, an
assistant professor of psychology at Harvard University. "In reality, our
memory is far less accurate than this."
In one study, Simons found that many people failed to notice
when an actor they were watching in a video was replaced by a different person
during a brief interruption, even though most people are confident they would
notice such a change. Only about one-third of his study subjects noticed the
change, even though the two actors were dressed differently.
And those were just casual observers. When you're actually
trying to remember something, your ability to pay attention may be even