Bounceback - About 750,000 Americans suffer a stroke each
year. In many cases, their ability to understand and use language
is severely impaired. Now scientists can see why this ability
is not lost for good. (10/18/02)
To Forget - Brain scientists are studying how we put painful
memories behind us. (11/27/02)
Elsewhere on the web
and Memory - from Radio National Australia
Emotions Strengthen Memory" - Library of Congress
Why do we remember emotional events so well? One memory researcher says itâ€™s
not just because theyâ€™re important to us.
As this ScienCentral News video reports, the findings suggest that we can manipulate
emotion to help improve our memory.
Drilling for memory
Students donâ€™t expect their teachers to encourage them to stop studying
at night to watch their favorite TV show. But when Kristy
Nielson tells her students at Marquette University itâ€™s okay to
do just that, she has a good reason why.
“I tell them, ‘Yeah, you can use me as an excuse for why you stopped
studying last night and watched Friends,â€™” she says. “Because
it may not be a bad thing to do to take that break, have that positive emotional
experience. Of course the only catch is, can we get them to get back to studying
Nielson has been researching the connection between emotion and memory for
more than a decade, and her work is disproving some previously held theories.
It was assumed that we remember emotional events so well because they are
important to us and we replay them in our minds over and over. But her work
shows that emotional events can help you remember things that are not related
to the event itself, as long as the two things occur within a close timeframe.
In her most
recent study, which was presented at the 2002
Society for Neuroscience conference, Nielson showed a group of students
a list of common, unrelated nouns. Then she showed the students either a video
illustrating proper tooth brushing technique, or one with uncensored footage
of someone undergoing a tooth extraction.
“It was unpleasant,” she says. “You see some blood and you
hear some drilling, and it's—people kind of describe it as giving them
the creepy crawlies.”
When she brought the students back 24-hours later, she asked them to recall
the words they had been shown the day before. Those who saw the gory dental
surgery video remembered, on average, 10 percent more of the words than those
who saw the tooth brushing video.
How it works
This work builds on previous studies on animals and humans, showing how “arousal”
can enhance memory. The chemical mechanism is adrenaline,
which studies suggest helps encode memories in our brain. The idea is that
when something emotional happens, you get a jolt of adrenaline that helps
you remember the moment, and even unimportant details around the moment, better
“We think that's a pretty natural biological mechanism to help differentiate
important from unimportant memories,” says Nielson. “I'm just
trying to manipulate that.”
That is, she wants to show how to use emotion or arousal to your own advantage,
and “take control of [your] own memory, and learn to enhance it when
you want to.” While watching a disturbing dental procedure can do the
trick, so can many other (and much less gross) things.
The adrenaline response can be elicited by positive emotional experiences.
One of Nielsonâ€™s previous studies showed that students
who received a dollar after learning the word list remembered the words
better than those who got nothing, a full week after the words were presented.
She thinks a funny event would also work, and she is currently recreating
her experiment using a clip from Saturday Night Live. But arousal is not restricted
to emotional events.
In one of her very first studies, Nielson showed people a word list, and had
some of them squeeze a “hand dynamometer”-sort of a fancy
stress ball that also measures muscle tension. That simple muscle tension
caused enough arousal, and therefore adrenaline, in the subjects to help them
remember the words better.
What it means for you
While manipulating arousal to help memory can apply to anyone who cares to
try, Nielson has three specific groups in mind: students, teachers (who can
manipulate the environment in which their students learn), and the elderly,
who lose control of their memory as the aging process wears on their brains.
Watching your favorite TV show, taking a jog around the block, listening to
your favorite album, squeezing a stress ball, or even eating a candy bar—all
these things might work. But Nielson cautions to use them in moderation. That
is, extremes of emotion or arousal tend to have a negative effect on memory.
“The video that I showed was unpleasant,” she says. “But
it wasn't what you would call traumatizing. If there were something that was
extremely violent or very traumatizing, then you might expect that it could
actually impair memory.”
She also does not yet know how long the window of opportunity is between the
learning experience and the emotional event. She hopes to tease that out in
Her current work is funded by Marquette University.