Old People Store Bad Memories Differently

Amelia Tomas, LiveScience Staff, LiveScience.com

Older adults use different parts of their brain than younger

people to store memories of the bad times, a finding that

may have to do with the resilience of seniors.

It is no surprise that older people tend to have more

difficulty trying to remember an array of events, but

neuroscientists from Duke University Medical Center

wanted to see how the connections that do this type of

memory work change with age.

So the researchers compared brain scans of older and

younger adults when the two groups were asked to

remember events that yielded unpleasant emotions. The

scans showed that while younger adults relied more on

the brain region involved in emotions (known as the

amygdala) and another involved in recalling memories (the

hippocampus), the elder subjects called upon a "higher

thinking" area of the brain called the frontal cortex.

The frontal cortex is an area of the brain that is involved

in complex cognitive functions such as planning,

organizing, problem-solving and abstract thoughts. It also

controls the lower-order parts of the brain such as the

amygdala.

Here are the experiment details:

The older and younger subject groups, with average ages

of 70 and 24 respectively, were hooked up to an fMRI 

machine and shown a series of 30 photographs, some of

which had strong negative content. Later they were asked

to complete a recall task to determine whether the brain

activity that occurred while looking at the pictures could

predict what types of content were memorized more

accurately.

Both age groups were equally affected by the emotional

content depicted by the pictures, such as violent acts or

attacking snakes. What differed were the brain

connections used to remember those pictures later on,

said Roberto Cabeza, a neuroscientist with Duke

University's Center for Cognitive Neuroscience.

And younger participants were able to recall more of the

emotional photos. They coupled their feelings more with

memory retrieval. The older people showed a reduction in

memory for pictures with a more negative emotional

content, indicating that perhaps with age, people learn to

be less affected by negative information in order to

maintain their well being and emotional states.

"It wasn't surprising that older people showed a reduction

in memory for negative pictures, but it was surprising that

the older subjects were using a different system to help

them to better encode those pictures they could

remember," said researcher Peggy St. Jacques, a

graduate student in the Cabeza laboratory.

The research is detailed online in the January 2009 issue

of the journal Psychological Science.

·           Video - Why We Age: A Genetic Clue 

·           Top 10 Mysteries of the Mind 

·           5 Ways to Beef Up Your Brain 

轉貼自︰

http://news.yahoo.com/s/livescience/oldpeoplestorebadmemoriesdifferently;_ylt=Av1CNcbaDZo_Jk4SDl4EFN8br7sF

本文於 修改第 2 次