Can bilingualism protect the brain even with early stages of dementia?

Researchers find bilingualism provides the brain with greater cognitive reserve, delaying onset of symptoms

February 13, 2020

Science Daily/York University

Psychology researchers provide new evidence that bilingualism can delay symptoms of dementia. Researchers found bilingualism provides the brain with greater cognitive reserve, delaying onset of symptoms.

Alzheimer's disease is the most common form of dementia, making up 60 to 70 per cent of dementia cases. Of all activities with neuroplastic benefits, language use is the most sustained, consuming the largest proportion of time within a day. It also activates regions across the entire brain. Ellen Bialystok, Distinguished Research Professor in York's Department of Psychology, Faculty of Health, and her team tested the theory that bilingualism can increase cognitive reserve and thus delay the age of onset of Alzheimer's disease symptoms in elderly patients.

Their study is believed to be the first to investigate conversion times from mild cognitive impairment to Alzheimer's disease in monolingual and bilingual patients. Although bilingualism delays the onset of symptoms, Bialystok says, once diagnosed, the decline to full-blown Alzheimer's disease is much faster in bilingual people than in monolingual people because the disease is actually more severe.

"Imagine sandbags holding back the floodgates of a river. At some point the river is going to win," says Bialystok. "The cognitive reserve is holding back the flood and at the point that they were when they were diagnosed with mild cognitive impairment they already had substantial pathology but there was no evidence of it because they were able to function because of the cognitive reserve. When they can no longer do this, the floodgates get completely washed out, so they crash faster."

In the five-year study, researchers followed 158 patients who had been diagnosed with mild cognitive impairment. For the study, they classified bilingual people as having high cognitive reserve and monolingual people as having low cognitive reserve.

Patients were matched on age, education, and cognitive level at the time of diagnosis of mild cognitive impairment. The researchers followed their six-month interval appointments at a hospital memory clinic to see the point at which diagnoses changed from mild cognitive impairment to Alzheimer's disease. The conversion time for bilinguals, 1.8 years after initial diagnosis, was significantly faster than it was for monolinguals, who took 2.6 years to convert to Alzheimer's disease. This difference suggests that bilingual patients had more neuropathology at the time they were diagnosed with mild cognitive impairment than the monolinguals, even though they presented with the same level of cognitive function.

These results contribute to the growing body of evidence showing that bilinguals are more resilient in dealing with neurodegeneration than monolinguals. They operate at a higher level of functioning because of the cognitive reserve, which means that many of these individuals will be independent longer, Bialystok says. This study adds new evidence by showing that the decline is more rapid once a clinical threshold has been crossed, presumably because there is more disease already in the brain.

"Given that there is no effective treatment for Alzheimer's or dementia, the very best you can hope for is keeping these people functioning so that they live independently so that they don't lose connection with family and friends. That's huge."

https://www.sciencedaily.com/releases/2020/02/200213132619.htm

AAN recommends people 65+ be screened yearly for memory problems

September 19, 2019

Science Daily/American Academy of Neurology

To help physicians provide the highest quality patient-centered neurologic care, the American Academy of Neurology (AAN) is recommending physicians measure how frequently they complete annual assessments of people age 65 and older for thinking and memory problems.

People with mild cognitive impairment have thinking and memory problems but usually do not know it because such problems are not severe enough to affect their daily activities. Yet mild cognitive impairment can be an early sign of Alzheimer's disease or other forms of dementia. It can also be a symptom of sleep problems, medical illness, depression, or a side effect of medications.

To help physicians provide the highest quality patient-centered neurologic care, the American Academy of Neurology (AAN) is recommending physicians measure how frequently they complete annual assessments of people age 65 and older for thinking and memory problems. This metric for yearly cognitive screening tests is part of an AAN quality measurement set published in the September 18, 2019, online issue of Neurology®, the medical journal of the American Academy of Neurology.

A quality measure is a mathematical tool to help physicians and practices understand how often health care services are consistent with current best practices and are based on existing AAN guideline recommendations. Quality measures are intended to drive quality improvement in practice. Physicians are encouraged to start small using one or two quality measures in practice that are meaningful for their patient population, and measure use is voluntary.

"Since thinking skills are the most sensitive indicator of brain function and they can be tested cost-effectively, this creates an enormous opportunity to improve neurologic care," said author Norman L. Foster, MD, of the University of Utah in Salt Lake City and a Fellow of the American Academy of Neurology. "The American Academy of Neurology is recommending the measurement of annual cognitive screenings for everyone age 65 and older because age itself is a significant risk factor for cognitive decline and mild cognitive impairment is increasingly prevalent with older age. The measure complements past American Academy of Neurology quality measures released for Parkinson's disease, multiple sclerosis and stroke, and allows for a doctor to meet the measure with a recommended periodic three-minute cognitive test."

According to the 2018 AAN guideline on mild cognitive impairment, nearly 7 percent of people in their early 60s worldwide have mild cognitive impairment, while 38 percent of people age 85 and older have it.

The new AAN quality measurement set recommends doctors measure how often they conduct annual screenings to improve the recognition of mild cognitive impairment and allow for earlier intervention.

"We cannot expect people to report their own memory and thinking problems because they may not recognize that they are having problems or they may not share them with their doctors," said Foster. "Annual assessments will not only help identify mild cognitive impairment early, it will also help physicians more closely monitor possible worsening of the condition."

The new measurement set states that documenting mild cognitive impairment in a person's medical record can be invaluable in alerting other physicians and medical staff so that the best care is provided to that patient.

Early diagnosis can help identify forms of mild cognitive impairment that may be reversible, including those caused by sleep problems, depression or medications, and lead to treatments that can improve a person's quality of life such as correcting hearing loss and avoiding social isolation.

When mild cognitive impairment is not reversible and could develop into more severe forms of dementia like Alzheimer's disease, the quality measurement set recommends measuring how frequently people are given information about their condition as early as possible, so they can take steps to avoid exploitation, plan for their care and monitor their condition.

It is also important not to forget about family and caregivers. The measurement set also asks doctors to identify care partners to help describe symptoms. Doctors should quantify involvement with family and caregivers and provide them with information so that they too receive support and get access to services to help them cope if person's illness progresses and to improve their well-being.

https://www.sciencedaily.com/releases/2019/09/190919093916.htm

Heart attack patients with mild cognitive impairment get fewer treatments

August 23, 2019

Science Daily/Michigan Medicine - University of Michigan

A new study finds people who have mild cognitive impairment (MCI), which lies on the continuum of cognitive decline between normal cognition and dementia, are less likely to receive proven heart attack treatment in the hospital.

Researchers found no evidence that those with MCI would derive less benefit from evidence-based treatment that's offered to their cognitively normal peers who have heart attacks, says lead author Deborah Levine, M.D., MPH.

"Patients should get the treatments they would want if they were properly informed," says Levine, an associate professor of internal medicine and neurology at Michigan Medicine, the academic medical center of the University of Michigan.

Some people with thinking, memory and language problems have MCI. Unlike dementia, which severely interferes with daily functioning and worsens over time, MCI does not severely interfere with daily functioning and might not worsen over time. Although people with MCI have an increased risk of developing dementia, it's not an inevitable next step, Levine says.

"While some may progress to dementia, many will persist in having MCI, and a few will actually improve and revert to normal cognition," says Levine, also a member of the University of Michigan Institute for Healthcare Policy and Innovation. "Many older adults with MCI live years with good quality of life, and so face common health risks of aging like heart attack and stroke.

"Clinicians, patients and families might be overestimating the risk of dementia after a mild cognitive impairment diagnosis even without realizing it. These older adults with MCI should still receive evidence-based treatments when indicated."

The research, published in the Journal of General Internal Medicine, found pre-existing MCI was associated with significantly lower use of guideline-concordant care after a heart attack, whether catheter-based or open surgery. The study measured 609 adults ages 65 and older who were hospitalized for a heart attack between 2000 and 2011.

Levine notes both cardiac catheterization (35% less likely in patients with pre-existing MCI) and coronary revascularization (45% less likely in patients with pre-existing MCI) have been shown to be highly effective at reducing deaths and improving physical functioning after heart attack in multiple large clinical trials.

'A timely issue'

Physicians must weigh the competing risks of all health problems that increase with age, Levine says, including heart disease and cognitive decline. Many families are dealing with both concerns at once in their older loved ones.

"This is a timely issue because as the population ages, the number of seniors 85 years old and older has become the fastest-growing segment of the U.S. population," Levine says. "Seniors 85 and older are most likely to have MCI, and their incidence of heart attack has surged."

However, cardiovascular disease, including heart attack and stroke, is still the leading cause of death and serious morbidity in older adults, whether they have MCI or normal cognitive functioning.

Up to 1 in 5 adults ages 65 and older has MCI, although many may be undiagnosed, Levine says. Since the Affordable Care Act mandated coverage of cognitive impairment assessments for Medicare beneficiaries, MCI diagnoses are expected to increase, she adds.

The need to question decision-making

Although much recent medical literature addresses overtreatment, Levine says this research shows undertreatment with high-value therapies can also be a problem.

Her team's ongoing research finds physicians might not be recommending invasive treatments as often after an older patient with some memory and thinking problems has a heart attack. She encourages clinicians to reflect on the influence of MCI in their decision-making.

"It's important for providers to consider whether they are recommending against treating a patient just because they have MCI," Levine says. "Physicians can think about offering treatments to all patients when clinically indicated."

Invasive treatments may not be indicated in those with advanced dementia or a limited life expectancy, she says, but MCI does not fall in that category.

This potential disconnect in provider recommendations provides an opportunity for patients and families to empower themselves by having conversations about the care they'd want if they become ill, she says. People with MCI can still participate in these types of discussions, and families don't need to wait until an event happens to start the conversation.

"In these discussions, patients and families often think about catastrophic illnesses where life support measures may be used, but heart attacks and stroke are much more common, and they're treatable," Levine says.

"Because dementia is so feared among older adults and their families, it's understandable and appropriate that it may weigh heavily on the decisions for all types of care, including heart attack care," adds co-author Kenneth Langa, M.D., Ph.D., a professor of internal medicine at Michigan Medicine and a member of the Institute for Healthcare Policy and Innovation. "Our study emphasizes the importance of differentiating between MCI and dementia and of educating patients, families and clinicians on the relative risks of further cognitive decline versus common cardiovascular conditions for people with MCI."

An ongoing effort

Levine and colleagues used data from the Health and Retirement Study, a nationally representative longitudinal study of older Americans that's based at U-M.

Heart attack, or acute myocardial infarction, was an appealing lens to research whether patients with MCI receive guideline-based treatment, Levine says. Heart attacks are acute, emergent medical problems that are common in seniors and have robust evidence of effective treatment, she adds.

Levine's team is also studying the effect of pre-existing MCI on treatment for acute ischemic stroke, and the reasons physician recommendations and patient preferences for effective treatment after stroke or heart attack might be different if the patient already has MCI.

"Studies like this are an important first step in raising awareness on MCI so that providers, like cardiologists, can make sure they offer the best therapies available during heart attacks," says senior author Brahmajee Nallamothu, M.D., MPH, an interventional cardiologist and professor of internal medicine at Michigan Medicine.

https://www.sciencedaily.com/releases/2019/08/190823182709.htm

Amyloid is a less accurate marker for measuring severity, progression of Alzheimer's

August 6, 2019

Science Daily/University of Pennsylvania School of Medicine

Researchers find fluorodeoxyglucose (FDG) PET is a better indicator of cognitive performance when compared to PET scans that detect amyloid protein.

While the presence of beta-amyloid plaques in the brain may be a hallmark of Alzheimer's disease, giving patients an amyloid PET scan is not an effective method for measuring their cognitive function, according to a new study from researchers in the Perelman School of Medicine at the University of Pennsylvania and Thomas Jefferson University. The researchers concluded that fluorodeoxyglucose (FDG) PET, which measures the brain's glucose consumption as a marker of neural activity, is a stronger approach for assessing the progression and severity of Alzheimer's and mild cognitive impairment (MCI) as compared to florbetapir-PET scans, which reveal amyloid protein deposits in the brain. This suggests that FDG-PET is also a better means for determining the effectiveness of Alzheimer's therapies, as well as tracking patients' disease advancement, in both clinical and research settings. Results of this study are detailed in the August issue of the Journal of Alzheimer's Disease.

"Both florbetapir-PET and FDG-PET are approved diagnostic methods for Alzheimer's disease, and both appear to be effective in indicating some sort of cognitive impairment. However, we have now shown that FDG-PET is significantly more precise in clinical studies, and it is also available for routine use with modest costs," said the study's co-principal investigator Abass Alavi, MD, PhD, a professor of Radiology at Penn. "Our results support the notion that amyloid imaging does not reflect levels of brain function, and therefore it may be of limited value for assessing patients with cognitive decline."

Alzheimer's disease, the most common cause of dementia, is the sixth leading cause of death in the United States, affecting up to 5.8 million Americans currently. As clinicians aim to spot and treat the symptoms of dementia in its earliest stages, PET plays an increasingly pivotal role in diagnosing and monitoring Alzheimer's disease, as well as MCI, a condition that often precedes dementia.

Two of the most significant biomarkers found in Alzheimer's are decreased glucose uptake and the accumulation of amyloid plaques in the brain. PET scans use different radioactive drugs, called radiotracers, to measure these biomarkers within the brain tissue of patients with cognitive impairment. FDG-PET is one of the most commonly used imaging techniques to diagnose Alzheimer's. However, in recent years, several other radiotracers, such as florbetapir, have been developed to detect the deposition of amyloid plaques.

Recently, the effectiveness of amyloid imaging as a strategy for monitoring dementia symptoms has been called into question. While the presence of amyloid plaques in the brain is considered as being characteristic of Alzheimer's, some studies have shown that large amounts of amyloid plaques were present in healthy, non-demented individuals. Conversely, recent clinical trials have shown that the intended removal of amyloid from the brains of patients with Alzheimer's disease led to no change in, or even worsened, cognitive performance.

In this study, the researchers evaluated 63 individuals, including 19 with clinically diagnosed Alzheimer's disease, 23 with MCI, and 21 healthy individuals. The study participants underwent both FDG- and florbetapir-PET imaging. They were then assessed with a Mini Mental Status Examination (MMSE), a widely used diagnostic test for detecting and assessing the severity of cognitive impairment. The researchers used a novel "global quantification approach" to generate data from five different regions of the brain, which were correlated with the results from the MMSE scores.

The study revealed that both FDG- and florbetapir-PET scans are able to effectively discriminate the individuals with dementia from the healthy control group. However, when compared with the MMSE scores, the correlation between low cognitive performance and high levels of amyloid was significantly weaker than the correlation between FDG and low cognitive performance for all groups included in the study. This suggests that FDG-PET is a more sensitive indicator of cognitive decline.

"Amyloid imaging has a value in diagnosing or ruling out Alzheimer's disease, but it's a bit like all or nothing. Our study shows that it can reveal disease, but you wouldn't be able to differentiate between someone who had very mild or very severe symptoms," said co-principal investigator Andrew Newberg, MD, a professor of Radiology at Thomas Jefferson University, who added that these findings have important implications for clinical research.

"In a clinical drug trial, for example, it may be more relevant to do an FDG-PET scan, rather than using amyloid as a marker, to find out whether the therapy is working," Newberg said.

While FDG-PET may not be a perfect diagnostic tool, the study confirms that currently it is the best available method for monitoring symptoms of dementia, according to Alavi.

"Right now, FDG is king when it comes to looking at brain function, not only in Alzheimer's disease, but also diseases like vascular dementia and cancer," Alavi said.

https://www.sciencedaily.com/releases/2019/08/190806121133.htm

Pink noise boosts deep sleep in mild cognitive impairment patients

Sound stimulation in deep sleep improved recall for some in small pilot study

June 28, 2019

Science Daily/Northwestern University

Gentle sound stimulation played during deep sleep enhanced deep sleep for people with mild cognitive impairment, who are at risk for Alzheimer's disease, a new study found. Those whose brains responded the most robustly to the sound stimulation showed an improved memory response the following day. These results suggest improving sleep is a promising novel approach to stave off dementia. The technology can be adapted for home use.

Gentle sound stimulation played during specific times during deep sleep enhanced deep or slow-wave sleep for people with mild cognitive impairment, who are at risk for Alzheimer's disease.

The individuals whose brains responded the most robustly to the sound stimulation showed an improved memory response the following day.

"Our findings suggest slow-wave or deep sleep is a viable and potentially important therapeutic target in people with mild cognitive impairment," said Dr. Roneil Malkani, assistant professor of neurology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine sleep medicine physician. "The results deepen our understanding of the importance of sleep in memory, even when there is memory loss."

Deep sleep is critical for memory consolidation. Several sleep disturbances have been observed in people with mild cognitive impairment. The most pronounced changes include reduced amount of time spent in the deepest stage of sleep.

"There is a great need to identify new targets for treatment of mild cognitive impairment and Alzheimer's disease," Malkani added. Northwestern scientists had previously shown that sound stimulation improved memory in older adults in a 2017 study.

Because the new study was small -- nine participants -- and some individuals responded more robustly than others, the improvement in memory was not considered statistically significant. However, there was a significant relationship between the enhancement of deep sleep by sound and memory: the greater the deep sleep enhancement, the better the memory response.

"These results suggest that improving sleep is a promising novel approach to stave off dementia," Malkani said.

The paper will be published June 28 in the Annals of Clinical and Translational Neurology.

For the study, Northwestern scientists conducted a trial of sound stimulation overnight in people with mild cognitive impairment. Participants spent one night in the sleep laboratory and another night there about one week later. Each participant received sounds on one of the nights and no sounds on the other. The order of which night had sounds or no sounds was randomly assigned. Participants did memory testing the night before and again in the morning. Scientists then compared the difference in slow-wave sleep with sound stimulation and without sounds, and the change in memory across both nights for each participant.

The participants were tested on their recall of 44 word pairs. The individuals who had 20% or more increase in their slow wave activity after the sound stimulation recalled about two more words in the memory test the next morning. One person with a 40% increase in slow wave activity remembered nine more words.

The sound stimulation consisted of short pulses of pink noise, similar to white noise but deeper, during the slow waves. The system monitored the participant's brain activity. When the person was asleep and slow brain waves were seen, the system delivered the sounds. If the patient woke up, the sounds stopped playing.

"As a potential treatment, this would be something people could do every night," Malkani said.

The next step, when funding is available, is to evaluate pink noise stimulation in a larger sample of people with mild cognitive impairment over multiple nights to confirm memory enhancement and see how long the effect lasts, Malkani said.

https://www.sciencedaily.com/releases/2019/06/190628120531.htm

Exercise may improve memory in heart failure patients

May 4, 2019

Science Daily/European Society of Cardiology

Two-thirds of patients with heart failure have cognitive problems, according to research presented today at EuroHeartCare 2019, a scientific congress of the European Society of Cardiology (ESC).1

Heart failure patients who walked further in a six-minute test, which shows better fitness, as well as those who were younger and more highly educated, were significantly less likely to have cognitive impairment. The results suggest that fitter patients have healthier brain function.

Study author Professor Ercole Vellone, of the University of Rome "Tor Vergata," Italy, said: "The message for patients with heart failure is to exercise. We don't have direct evidence yet that physical activity improves cognition in heart failure patients, but we know it improves their quality and length of life. In addition, studies in older adults have shown that exercise is associated with improved cognition -- we hope to show the same for heart failure patients in future studies."

The cognitive abilities that are particularly damaged in heart failure patients are memory, processing speed (time it takes to understand and react to information), and executive functions (paying attention, planning, setting goals, making decisions, starting tasks).

"These areas are important for memorising healthcare information and having the correct understanding and response to the disease process," said Professor Vellone. "For example, heart failure patients with mild cognitive impairment may forget to take medicines and may not comprehend that weight gain is an alarming situation that requires prompt intervention."

The study highlights that cognitive dysfunction is a common problem in patients with heart failure -- 67% had at least mild impairment. "Clinicians might need to adapt their educational approach with heart failure patients -- for example involving a family caregiver to oversee patient adherence to the prescribed treatment," said Professor Vellone.

The study used data from the HF-Wii study, which enrolled 605 patients with heart failure from six countries. The average age was 67 and 71% were male. The Montreal Cognitive Assessment test was used to measure cognitive function and exercise capacity was measured with the six-minute walk test.

Professor Vellone said: "There is a misconception that patients with heart failure should not exercise. That is clearly not the case. Find an activity you enjoy that you can do regularly. It could be walking, swimming, or any number of activities. There is good evidence that it will improve your health and your memory, and make you feel better."

https://www.sciencedaily.com/releases/2019/05/190504130301.htm

Eating mushrooms may reduce the risk of cognitive decline

March 12, 2019

Science Daily/National University of Singapore

Researchers found that seniors who consume more than two standard portions of mushrooms weekly may have 50 percent reduced odds of having mild cognitive impairment.

A team from the Department of Psychological Medicine and Department of Biochemistry at the Yong Loo Lin School of Medicine at the National University of Singapore (NUS) has found that seniors who consume more than two standard portions of mushrooms weekly may have 50 per cent reduced odds of having mild cognitive impairment (MCI).

A portion was defined as three quarters of a cup of cooked mushrooms with an average weight of around 150 grams. Two portions would be equivalent to approximately half a plate. While the portion sizes act as a guideline, it was shown that even one small portion of mushrooms a week may still be beneficial to reduce chances of MCI.

"This correlation is surprising and encouraging. It seems that a commonly available single ingredient could have a dramatic effect on cognitive decline," said Assistant Professor Lei Feng, who is from the NUS Department of Psychological Medicine, and the lead author of this work.

The six-year study, which was conducted from 2011 to 2017, collected data from more than 600 Chinese seniors over the age of 60 living in Singapore. The research was carried out with support from the Life Sciences Institute and the Mind Science Centre at NUS, as well as the Singapore Ministry of Health's National Medical Research Council. The results were published online in the Journal of Alzheimer's Disease on 12 March 2019.

Determining MCI in seniors

MCI is typically viewed as the stage between the cognitive decline of normal ageing and the more serious decline of dementia. Seniors afflicted with MCI often display some form of memory loss or forgetfulness and may also show deficit on other cognitive function such as language, attention and visuospatial abilities. However, the changes can be subtle, as they do not experience disabling cognitive deficits that affect everyday life activities, which is characteristic of Alzheimer's and other forms of dementia.

"People with MCI are still able to carry out their normal daily activities. So, what we had to determine in this study is whether these seniors had poorer performance on standard neuropsychologist tests than other people of the same age and education background," explained Asst Prof Feng. "Neuropsychological tests are specifically designed tasks that can measure various aspects of a person's cognitive abilities. In fact, some of the tests we used in this study are adopted from commonly used IQ test battery, the Wechsler Adult Intelligence Scale (WAIS)."

As such, the researchers conducted extensive interviews and tests with the senior citizens to determine an accurate diagnosis. "The interview takes into account demographic information, medical history, psychological factors, and dietary habits. A nurse will measure blood pressure, weight, height, handgrip, and walking speed. They will also do a simple screen test on cognition, depression, anxiety," said Asst Prof Feng.

After this, a two-hour standard neuropsychological assessment was performed, along with a dementia rating. The overall results of these tests were discussed in depth with expert psychiatrists involved in the study to get a diagnostic consensus.

Mushrooms and cognitive impairment

Six commonly consumed mushrooms in Singapore were referenced in the study. They were golden, oyster, shiitake and white button mushrooms, as well as dried and canned mushrooms. However, it is likely that other mushrooms not referenced would also have beneficial effects.

The researchers believe the reason for the reduced prevalence of MCI in mushroom eaters may be down to a specific compound found in almost all varieties. "We're very interested in a compound called ergothioneine (ET)," said Dr Irwin Cheah, Senior Research Fellow at the NUS Department of Biochemistry. "ET is a unique antioxidant and anti-inflammatory which humans are unable to synthesise on their own. But it can be obtained from dietary sources, one of the main ones being mushrooms."

An earlier study by the team on elderly Singaporeans revealed that plasma levels of ET in participants with MCI were significantly lower than age-matched healthy individuals. The work, which was published in the journal Biochemical and Biophysical Research Communications in 2016, led to the belief that a deficiency in ET may be a risk factor for neurodegeneration, and increasing ET intake through mushroom consumption might possibly promote cognitive health.

Other compounds contained within mushrooms may also be advantageous for decreasing the risk of cognitive decline. Certain hericenones, erinacines, scabronines and dictyophorines may promote the synthesis of nerve growth factors. Bioactive compounds in mushrooms may also protect the brain from neurodegeneration by inhibiting production of beta amyloid and phosphorylated tau, and acetylcholinesterase.

Next steps

The potential next stage of research for the team is to perform a randomised controlled trial with the pure compound of ET and other plant-based ingredients, such as L-theanine and catechins from tea leaves, to determine the efficacy of such phytonutrients in delaying cognitive decline. Such interventional studies will lead to more robust conclusion on causal relationship. In addition, Asst Prof Feng and his team also hope to identify other dietary factors that could be associated with healthy brain ageing and reduced risk of age-related conditions in the future.

https://www.sciencedaily.com/releases/2019/03/190312103702.htm

Exercise may be the best medicine for Alzheimer's disease

July 30, 2013

Science Daily/University of Maryland

Regular, moderate exercise could improve memory and cognitive function in those at risk for Alzheimer's disease in a way no drug can. Scientists studied the effects of exercise on a group of older adults with mild cognitive impairment and found that brain activity associated with memory, measured by neuroimaging, improved after 12 weeks of a moderate exercise program.

New research out of the University of Maryland School of Public Health shows that exercise may improve cognitive function in those at risk for Alzheimer's by improving the efficiency of brain activity associated with memory. Memory loss leading to Alzheimer's disease is one of the greatest fears among older Americans. While some memory loss is normal and to be expected as we age, a diagnosis of mild cognitive impairment, or MCI, signals more substantial memory loss and a greater risk for Alzheimer's, for which there currently is no cure.

The study, led by Dr. J. Carson Smith, assistant professor in the Department of Kinesiology, provides new hope for those diagnosed with MCI. It is the first to show that an exercise intervention with older adults with mild cognitive impairment (average age 78) improved not only memory recall, but also brain function, as measured by functional neuroimaging (via fMRI). The findings are published in the Journal of Alzheimer's Disease.

"We found that after 12 weeks of being on a moderate exercise program, study participants improved their neural efficiency -- basically they were using fewer neural resources to perform the same memory task," says Dr. Smith. "No study has shown that a drug can do what we showed is possible with exercise."

Recommended Daily Activity: Good for the Body, Good for the Brain

Two groups of physically inactive older adults (ranging from 60-88 years old) were put on a 12-week exercise program that focused on regular treadmill walking and was guided by a personal trainer. Both groups -- one which included adults with MCI and the other with healthy brain function -- improved their cardiovascular fitness by about ten percent at the end of the intervention. More notably, both groups also improved their memory performance and showed enhanced neural efficiency while engaged in memory retrieval tasks.

The good news is that these results were achieved with a dose of exercise consistent with the physical activity recommendations for older adults. These guidelines urge moderate intensity exercise (activity that increases your heart rate and makes you sweat, but isn't so strenuous that you can't hold a conversation while doing it) on most days for a weekly total of 150 minutes.

Measuring Exercise's Impact on Brain Health and Memory

One of the first observable symptoms of Alzheimer's disease is the inability to remember familiar names. Smith and colleagues had study participants identify famous names and measured their brain activation while engaged in correctly recognizing a name -- e.g., Frank Sinatra, or other celebrities well known to adults born in the 1930s and 40s. "The task gives us the ability to see what is going on in the brain when there is a correct memory performance," Smith explains.

Tests and imaging were performed both before and after the 12-week exercise intervention. Brain scans taken after the exercise intervention showed a significant decrease in the intensity of brain activation in eleven brain regions while participants correctly identified famous names. The brain regions with improved efficiency corresponded to those involved in the pathology of Alzheimer's disease, including the precuneus region, the temporal lobe, and the parahippocampal gyrus.

The exercise intervention was also effective in improving word recall via a "list learning task," i.e., when people were read a list of 15 words and asked to remember and repeat as many words as possible on five consecutive attempts, and again after a distraction of being given another list of words.

"People with MCI are on a very sharp decline in their memory function, so being able to improve their recall is a very big step in the right direction," Smith states.

The results of Smith's study suggest that exercise may reduce the need for over-activation of the brain to correctly remember something. That is encouraging news for those who are looking for something they can do to help preserve brain function.

Dr. Smith has plans for a larger study that would include more participants, including those who are healthy but have a genetic risk for Alzheimer's, and follow them for a longer time period with exercise in comparison to other types of treatments. He and his team hope to learn more about the impact of exercise on brain function and whether it could delay the onset or progression of Alzheimer's disease.

http://www.sciencedaily.com/releases/2013/07/130730123249.htm

Memory May Decline Rapidly Even in Stage Before Alzheimer's Disease

March 23, 2010

Science Daily/American Academy of Neurology

Memory and thinking skills may decline rapidly for people who have mild cognitive impairment, which is the stage before Alzheimer's disease when people have mild memory problems but no dementia symptoms, and even more rapidly when dementia begins, which is when Alzheimer's disease is usually diagnosed.

"These results show that we need to pay attention to this time before Alzheimer's disease is diagnosed, when people are just starting to have problems forgetting things," said study author Robert S. Wilson, PhD, of Rush University Medical Center in Chicago.

"The changes in rate of decline occur as the brain atrophies due to the disease, first mainly in the hippocampus during the initial symptomatic stage, referred to as mild cognitive impairment, then in the temporal, parietal and frontal cortex during the dementing illness phase of Alzheimer's disease," said David S. Knopman, MD, of the Mayo Clinic in Rochester, Minn., and Fellow of the American Academy of Neurology, who wrote an editorial accompanying the article.

http://www.sciencedaily.com/releases/2010/03/100322171008.htm