True and false memories activate different brain regions

By Tom Nordlie • Published: February 11th, 2008
Category: Health in a Heartbeat

You’ve heard this story before.

Uncle Fred’s describing how he saw President Kennedy assassinated.

Fred was just a boy but he recalls the events vividly.

Only thing is, you’ve seen the home movies Fred’s mother made that fateful day.

The president’s motorcade passed by uneventfully. The assassination happened blocks away.

Fred’s not lying. He believes what he says.

It’s an example of false memory, a condition that causes people to remember distorted versions of real events, or recall things that never happened.

Scientists aren’t sure what causes false memory.

Some research suggests it can come about when people visualize things repeatedly.

A recent study in The Journal of Neuroscience supports that hypothesis.

Using word-recognition tests and M-R-I scans, researchers showed that genuine memories and honest mistakes activate different parts of the brain.

In the study, volunteers saw short lists of words that fit a category, such as farm animals.

Later, the volunteers saw individual words, and indicated whether they appeared on the lists.

Some had, but others were new words that fit the categories.

Accurate recollections activated a region of the brain associated with memory.

But when volunteers mistakenly believed they remembered the new words, there was more activity in a region used to recognize familiar things.

So perhaps Uncle Fred heard so much about J-F-K’s death that he began to think he’d witnessed it.

There’s a saying that goes, “perception is reality.”

Perhaps we should add a phrase inspired by television advertising… perception is subject to change without notice.