Senior Citizens Remember Fewer Negative Pictures,
Use Brains Differently
Older people dwell in a world with a lot of
negatives, perhaps they have learned to reduce the impact of negative
information and remember in a different way
Dec.
16, 2008 It probably wont surprise many senior citizens, but
neuroscientists claim to have discovered that older people use their
brains differently than younger people when it comes to storing
memories, particularly those associated with negative emotions.
The study from Duke University Medical Center,
which will appear online in the January issue of Psychological
Science, is a novel look at how brain connections change with age.
Old folks who live longest are happy, healthy, rich
people that don't smoke and control drinking. Was that ever a mystery?
Is this the study to no where?
Older adults, average age 70, and younger adults,
average age 24, were shown a series of 30 photographs while their brains
were imaged in a functional MRI (fMRI) machine. Some of the photos were
neutral in nature and others had strong negative content such as
attacking snakes, mutilated bodies and violent acts.
While in the fMRI machine, the subjects looked at
the photos and ranked them on a pleasantness scale.
Then they completed an unexpected recall task
following the fMRI scan to determine whether the brain activity that
occurred while looking at the pictures could predict later memory. The
results were sorted according to the numbers of negative and neutral
pictures that were remembered or missed by each group.
The scientists found that older adults have less
connectivity between an area of the brain that generates emotions and a
region involved in memory and learning.
But they also found that the older adults have
stronger connections with the frontal cortex, the higher thinking area
of the brain that controls these lower-order parts of the brain.
Young adults used more of the brain regions
typically involved in emotion and recalling memories.
"The younger adults were able to recall more of the
negative photos," said Roberto Cabeza, Ph.D., senior author and Duke
professor in the Center for Cognitive Neuroscience.
If the older adults are using more thinking than
feeling, "that may be one reason why older adults showed a reduction in
memory for pictures with a more negative emotional content."
"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 lead author Peggy St.
Jacques, a graduate student in the Cabeza laboratory.
The emotional centers of the older subjects were as
active as those of younger subjects - it was the brain connections that
differed.
"If using the frontal regions to perform a memory
task was always beneficial, then the young people would use that
strategy, too," Cabeza said.
"Each way of doing a task has some trade-offs.
Older people have learned to be less affected by negative information in
order to maintain their well being and emotional state they may have
sacrificed more accurate memory for a negative stimulus, so that they
won't be so affected by it."
"Perhaps at different stages of life, there are
different brain strategies," Cabeza speculated.
"Younger adults might need to keep an accurate
memory for both positive and negative information in the world. Older
people dwell in a world with a lot of negatives, so perhaps they have
learned to reduce the impact of negative information and remember in a
different way."
According to Cabeza, the results of the study are
consistent with a theory about emotional processes in older adults
proposed by Dr. Laura Carstensen at Stanford University, an expert in
cognitive processing in old age.
"One thing we might do in the future is to ask
subjects to try to actively regulate their emotions as they look at the
pictures," St. Jacques said. "Would there be a shift in the neural
networks for processing the negative pictures when we asked younger
people to regulate their emotional responses? How would that affect
their later recall of the negative pictures?"
Background Information
The other author on the study was Florin Dolcos,
who is now at the Department of Psychiatry, University of Alberta, in
Edmonton, Canada.
The study was funded by the National Institutes of
Health, a postdoctoral fellowship from the Natural Sciences and
Engineering Research Council of Canada, an award from the Canadian
Psychiatric Research Foundation, and a Young Investigator Award from the
U.S. National Alliance for Research on Schizophrenia and Depression.
Keep up with the latest news for senior citizens, baby
boomers
Dec.
16, 2008 It probably wont surprise many senior citizens, but
neuroscientists claim to have discovered that older people use their
brains differently than younger people when it comes to storing
memories, particularly those associated with negative emotions.
Old folks who live longest are happy, healthy, rich
people that don't smoke and control drinking. Was that ever a mystery?
Is this the study to no where?