Studies Suggest People with Early AD Can Still Learn
People who have early stage Alzheimer's disease (AD) could be more
capable of learning than previously thought, according to two new
studies supported by the National Institute on Aging (NIA), a part
of the National Institutes of Health. The promising studies suggest
that some people with early cognitive impairment can still be taught
to recall important information and to better perform daily tasks.
In a July 2004 report, researchers in Miami, FL, found mildly impaired
AD patients who participated in 3-to-4 months of cognitive rehabilitation
had a 170 percent improvement, on average, in their ability to recall
faces and names and a 71 percent improvement in their ability to
provide proper change for a purchase. The participants also could
respond to and process information more rapidly and were better
oriented to time and place compared to a similar group of AD patients
who did not receive this targeted intervention. These improvements
were still evident 3 months after the cognitive training ended.
The findings, by David A. Loewenstein, Ph.D., and colleagues at
the University of Miami School of Medicine and Mount Sinai Medical
Center, Miami Beach, are reported in the July-August 2004 issue
of the American Journal of Geriatric Psychiatry.
The Loewenstein report follows a recent study by researchers at
Washington University in St. Louis who found that older people with
early-stage AD retained functioning levels of implicit memory similar
to young adults and older adults who did not have AD. Implicit memory
is relatively unconscious and automatic: Information from the past
"pops into mind" without a deliberate effort to remember.
This unconscious, implicit memory is important for common skills
and activities, such as speaking a language or riding a bicycle.
In many cases, people implicitly remember how to perform these activities,
without being able to deliberately remember when or where they learned
them. The study by Cindy Lustig, Ph.D., and Randy Buckner, Ph.D.,
appeared in the June 10, 2004, issue of Neuron.
"Taken together, these studies introduce the exciting notion
that older people who are in the early stages of AD can be taught
techniques to help stay engaged in everyday life," says Neil
Buckholtz, Ph.D., head of the Dementias of Aging Branch at the NIA.
"These findings show it is possible to pinpoint what memory
capabilities are preserved in early AD and suggest ways to target
those memory functions and make the most of them."
Cognition is the ability to think, learn, and remember. Previous
studies have shown that cognitive rehabilitation can effectively
improve memory and other cognitive functions in people who have
had strokes or suffered traumatic brain injuries. Some of these
techniques also have helped improve memory in some people with AD.
However, the current research reported by Loewenstein and colleagues
is believed to be the first to combine several specific cognitive
memory techniques into a single rehabilitation program for those
who are mildly impaired with AD.
Dr. Loewenstein and colleagues randomly assigned 44 people who were
diagnosed with AD into two groups. All participants in the study
were taking cholinesterase inhibitor medications, such as donepezil
(Aricept), which may help prevent AD symptoms from becoming worse
for a limited time.
The 25 people in the "cognitive rehabilitation" (CR) group
participated in two 45-minute sessions weekly for a total of 24
sessions. During these sessions, they learned face-name recognition
techniques, such as associating a prominent facial feature with
a name. So a smiling man named Sam might be recalled as "Smiling
Sam." To enhance time and place orientation, CR participants
were given memory notebooks and encouraged to record appointments,
medication schedules, and contact information for relatives, friends,
and doctors in them. The participants were asked to review this
central information repository twice daily throughout the study.
They also were taught effective ways to make change for a purchase
and asked to use a calculator to balance a checkbook after paying
three bills. In addition, they learned to click a mouse button in
response to yellow boxes as they randomly appeared on a computer
screen. This technique was designed to improve attention span and
cognitive processing speed. Finally, the CR group was asked to manipulate
objects, such as a key, as though they were using them, a technique
that can jumpstart memory in some people. In addition, participants
and their caregivers were encouraged to practice all of these techniques
at home.
The 19 participants in a "mental stimulation" (MS) group
played computer games that required memory, concentration, and problem-solving
skills. In addition, participants in this group were asked to discuss
various topics, such as describing the neighborhood in which they
grew up. They also were asked to do crossword puzzles, word scrambles,
and other "homework" assignments.
At the end of the study, those in the rehabilitation group showed,
on average, significantly improved ability to associate faces and
names, had faster mental processing speeds, were better oriented
to time and place, and were better able to make correct change for
purchases than those in the MS group. However, neither group showed
memory improvement for manipulating objects or balancing a checkbook.
"Our study shows that people with early AD can learn. This
learning can be greatly enhanced if you teach them certain techniques
that target particular areas of the brain," Dr. Loewenstein
says. "More importantly, by combining specific cognitive rehabilitation
strategies, we can help people with AD remain engaged in daily activities
and retain a connection to their family and friends and the world
as a whole for a longer period of time."
The June 2004 study by Lustig and Buckner recruited 34 young adults,
33 older adults without any Alzheimer's symptoms, and 24 older adults
with symptoms of early-stage AD. The study examined a type of implicit
memory that helps people act faster on items they have previously
worked on than new items. In the study, participants were shown
words and asked to judge if they represented something living, such
as the word "DOG" or something nonliving, such as the
word "DESK". Overall, the young adults made faster judgments
than their older peers and those who had AD. However, all three
groups were faster when shown repeated words rather than new ones.
This increase was about the same for all three groups, suggesting
that this benefit of implicit memory remains in old age and even
early Alzheimer's disease.
The researchers also used functional magnetic resonance imaging
(fMRI) to measure brain activity during the word judgments. They
were especially interested in the left prefrontal cortex, a part
of the brain involved in thinking about what words mean. They found
that activity in this part of the brain was less for repeated words
than for new ones. Along with the faster judgments, this reduction
in brain activity suggests that seeing an item again had an important
effect. Because the judgment for a word was made when the person
saw it initially, the brain didn't have to work as hard at making
a living/non-living judgment when the same word appeared again.
In fact, even when people with AD couldn't remember which words
they had seen, presenting the words again still helped them classify
those words faster, and they also showed changes in brain activity
like those of the young adults and their healthy older peers.
"One of the exciting findings from our study is the suggestion
that the brain areas supporting high level, complex thinking still
have some flexibility and these areas can change with some learning
as we age and even in early AD," Dr. Lustig says. "We're
hoping our results will be useful in designing cognitive training
and rehabilitation programs." In addition to the NIA, Lustig
and Buckner's study was supported by the Alzheimer's Association and the James S. McDonnell
Foundation. Dr. Buckner is a Howard Hughes Medical Institute investigator.
AD is an irreversible disorder of the brain, robbing those who have
it of memory, and eventually, overall mental and physical function,
leading to death. It is the most common cause of dementia among
people over age 65, affecting an estimated 4.5 million Americans.
For more information on AD research, as well as on biological,
epidemiological, clinical, and social and behavioral research on
AD, several publications are available from the NIA including: 2001-2002
Alzheimer's Disease Progress Report and Alzheimer's Disease: Unraveling
the Mystery, which includes a CD-Rom animation of what happens
to the brain in AD. Caregiver Guide: Tips for Caregivers of People
with Alzheimer's Disease from the National Institute on Aging
also is available. These publications may be viewed at NIA's AD-dedicated
website www.alzheimers.org,
the Institute's Alzheimer's Disease Education and Referral (ADEAR)
Center, or by calling ADEAR at 1-800-438-4380.
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