A rich vocabulary can protect against cognitive impairment

Some people suffer incipient dementia as they get older. To make up for this loss, the brain’s cognitive reserve is put to the test. Researchers from the University of Santiago de Compostela have studied what factors can help to improve this ability and they conclude that having a higher level of vocabulary is one such factor.

‘Cognitive reserve’ is the name given to the brain’s capacity to compensate for the loss of its functions. This reserve cannot be measured directly; rather, it is calculated through indicators believed to increase this capacity.

A research project at the University of Santiago de Compostela (USC) has studied how having a wide vocabulary influences cognitive reserve in the elderly.

As Cristina Lojo Seoane, from the USC, co-author of the study published in the journal ‘Anales de Psicología’(Annals of Psychology), explains to SINC: “We focused on level of vocabulary as it is considered an indicator of crystallised intelligence (the use of previously acquired intellectual skills). We aimed to deepen our understanding of its relation to cognitive reserve.”

The research team chose a sample of 326 subjects over the age of 50 – 222 healthy individuals and 104 with mild cognitive impairment. They then measured their levels of vocabulary, along with other measures such as their years of schooling, the complexity of their jobs and their reading habits.

They also analysed the scores they obtained in various tests, such as the vocabulary subtest of the ‘Wechsler Adult Intelligence Scale’(WAIS) and the Peabody Picture Vocabulary Test.

“With a regression analysis we calculated the probability of impairment to the vocabulary levels of the participants,” Lojo Seoane continues.

The results revealed a greater prevalence of mild cognitive impairment in participants who achieved a lower vocabulary level score.

“This led us to the conclusion that a higher level of vocabulary, as a measure of cognitive reserve, can protect against cognitive impairment,” the researcher concludes.

Physical exercise in old age can stimulate brain fitness, but effect decreases with advancing age

Physical exercise in old age can improve brain perfusion as well as certain memory skills. This is the finding of Magdeburg neuroscientists who studied men and women aged between 60 and 77. In younger individuals regular training on a treadmill tended to improve cerebral blood flow and visual memory. However, trial participants who were older than 70 years of age tended to show no benefit of exercise. Thus, the study also indicates that the benefits of exercise may be limited by advancing age. Researchers of the German Center for Neurodegenerative Diseases (DZNE), the University of Magdeburg and the Leibniz Institute for Neurobiology have published these results in the current edition of the journal “Molecular Psychiatry”. Scientists at the Karolinska Institute in Stockholm and the Max Planck Institute for Human Development were also involved in the study.

Exercise key to warding off dementia

EXERCISE is one of the best ways to protect against dementia in later life and the earlier you start, the greater the effect, research suggests.

Participating in intellectually stimulating leisure activities, paid work, volunteer work or study can also help protect against memory loss and reduce the risk of developing Alzheimer’s disease.

UWA adjunct clinical professor Nicola Lautenschlager, who led a review of strategies to delay cognitive decline, says there is a growing body of evidence that suggests exercise is beneficial for brain health.

"The knowledge we have so far basically makes it very clear that regular physical activity, even at an older age, can be very beneficial for protecting cognition," she says.

"Beyond that it’s also very effective for protecting or maintaining mental health, especially in relation to symptoms of depression or anxiety."

Prof Lautenschlager, who is based at the University of Melbourne, says older people who are well enough are advised to do 150 minutes of physical activity a week, such as going for walks.

"When it comes [to] brain health…it would be good if the walking speed isn’t very slow, so it shouldn’t be a stroll but rather what we call moderate pace," she says.

"Research has shown that the level of physical activity has to have a certain intensity so that the brain benefits."

Enjoyable hobbies key to brain health

Hobbies that keep the brain active, such as playing an instrument, going to concerts or joining a book club, can also be very helpful as long as it is an activity a person enjoys, Prof Lautenschlager says.

"The minute you prescribe an activity they hate doing…most likely the effect in terms of being beneficial for brain health is lost," she says.

"It produces so much stress in the body not wanting to do it that the stress is more harmful than the benefit of keeping the brain active."

Prof Lautenschlager says middle age is a crucial time for making lifestyle decisions that will determine a person’s health in later life.

"Usually we are talking about when you move into your 30s, definitely the 40s and also still the 50s," she says.

"Things like a high blood pressure or carrying too much weight, if you do that in these decades, it seems to harm the brain long-term in terms of how healthy a person is in their 70s or 80s."

Ideally people should aim for a healthy lifestyle from childhood but luckily research shows lifestyle changes still have an effect on brain health if a person is already old, Prof Lautenschlager says.

"Even programs…with seniors in their 70s and 80s can still make a difference," she says.

The research was published this month in the journal Maturitas.

Memory loss associated with Alzheimer’s reversed for first time

Since its first description over 100 years ago, Alzheimer’s disease has been without effective treatment. That may finally be about to change: in the first, small study of a novel, personalized and comprehensive program to reverse memory loss, nine of 10 participants, including the ones above, displayed subjective or objective improvement in their memories beginning within 3-to-6 months after the program’s start. Of the six patients who had to discontinue working or were struggling with their jobs at the time they joined the study, all were able to return to work or continue working with improved performance. Improvements have been sustained, and as of this writing the longest patient follow-up is two and one-half years from initial treatment. These first ten included patients with memory loss associated with Alzheimer’s disease (AD), amnestic mild cognitive impairment (aMCI), or subjective cognitive impairment (SCI; when a patient reports cognitive problems). One patient, diagnosed with late stage Alzheimer’s, did not improve.

The study, which comes jointly from the UCLA Mary S. Easton Center for Alzheimer’s Disease Research and the Buck Institute for Research on Aging, is the first to suggest that memory loss in patients may be reversed, and improvement sustained, using a complex, 36-point therapeutic program that involves comprehensive changes in diet, brain stimulation, exercise, optimization of sleep, specific pharmaceuticals and vitamins, and multiple additional steps that affect brain chemistry.

The findings, published in the current online edition of the journal Aging, “are very encouraging. However, at the current time the results are anecdotal, and therefore a more extensive, controlled clinical trial is warranted,” said Dale Bredesen, the Augustus Rose Professor of Neurology and Director of the Easton Center at UCLA, a professor at the Buck Institute, and the author of the paper.

In the case of Alzheimer’s disease, Bredesen notes, there is not one drug that has been developed that stops or even slows the disease’s progression, and drugs have only had modest effects on symptoms. “In the past decade alone, hundreds of clinical trials have been conducted for Alzheimer’s at an aggregate cost of over a billion dollars, without success,” he said.

Other chronic illnesses such as cardiovascular disease, cancer, and HIV, have been improved through the use of combination therapies, he noted. Yet in the case of Alzheimer’s and other memory disorders, comprehensive combination therapies have not been explored. Yet over the past few decades, genetic and biochemical research has revealed an extensive network of molecular interactions involved in AD pathogenesis. “That suggested that a broader-based therapeutics approach, rather than a single drug that aims at a single target, may be feasible and potentially more effective for the treatment of cognitive decline due to Alzheimer’s,” said Bredesen.

While extensive preclinical studies from numerous laboratories have identified single pathogenetic targets for potential intervention, in human studies, such single target therapeutic approaches have not borne out. But, said Bredesen, it’s possible addressing multiple targets within the network underlying AD may be successful even when each target is affected in a relatively modest way. “In other words,” he said, “the effects of the various targets may be additive, or even synergistic.”

The uniform failure of drug trials in Alzheimer’s influenced Bredesen’s research to get a better understanding of the fundamental nature of the disease. His laboratory has found evidence that Alzheimer’s disease stems from an imbalance in nerve cell signaling: in the normal brain, specific signals foster nerve connections and memory making, while balancing signals support memory loss, allowing irrelevant information to be forgotten. But in Alzheimer’s disease, the balance of these opposing signals is disturbed, nerve connections are suppressed, and memories are lost.

The model of multiple targets and an imbalance in signaling runs contrary to the popular dogma that Alzheimer’s is a disease of toxicity, caused by the accumulation of sticky plaques in the brain. Bredesen believes the amyloid beta peptide, the source of the plaques, has a normal function in the brain – as part of a larger set of molecules that promotes signals that cause nerve connections to lapse. Thus the increase in the peptide that occurs in Alzheimer’s disease shifts the memory-making vs. memory-breaking balance in favor of memory loss.

Given all this, Bredesen thought that rather than a single targeted agent, the solution might be a systems type approach, the kind that is in line with the approach taken with other chronic illnesses—a multiple-component system.

“The existing Alzheimer’s drugs affect a single target, but Alzheimer’s disease is more complex. Imagine having a roof with 36 holes in it, and your drug patched one hole very well—the drug may have worked, a single “hole” may have been fixed, but you still have 35 other leaks, and so the underlying process may not be affected much.”

Bredesen’s approach is personalized to the patient, based on extensive testing to determine what is affecting the plasticity signaling network of the brain. As one example, in the case of the patient with the demanding job who was forgetting her way home, her therapeutic program consisted of some, but not all of the components involved with Bredesen’s therapeutic program, and included:

(1) eliminating all simple carbohydrates, leading to a weight loss of 20 pounds; (2) eliminating gluten and processed food from her diet, with increased vegetables, fruits, and non-farmed fish; (3) to reduce stress, she began yoga; (4) as a second measure to reduce the stress of her job, she began to meditate for 20 minutes twice per day; (5) she took melatonin each night; (6) she increased her sleep from 4-5 hours per night to 7-8 hours per night; (7) she took methylcobalamin each day; (8) she took vitamin D3 each day; (9) fish oil each day; (10) CoQ10 each day; (11) she optimized her oral hygiene using an electric flosser and electric toothbrush; (12) following discussion with her primary care provider, she reinstated hormone replacement therapy that had been discontinued; (13) she fasted for a minimum of 12 hours between dinner and breakfast, and for a minimum of three hours between dinner and bedtime; (14) she exercised for a minimum of 30 minutes, 4-6 days per week.

The results for nine of the 10 patients reported in the paper suggest that memory loss may be reversed, and improvement sustained with this therapeutic program, said Bredesen. “This is the first successful demonstration,” he noted, but he cautioned that the results are anecdotal, and therefore a more extensive, controlled clinical trial is needed.

The downside to this program is its complexity. It is not easy to follow, with the burden falling on the patients and caregivers, and none of the patients were able to stick to the entire protocol. The significant diet and lifestyle changes, and multiple pills required each day, were the two most common complaints. The good news, though, said Bredesen, are the side effects: “It is noteworthy that the major side effect of this therapeutic system is improved health and an optimal body mass index, a stark contrast to the side effects of many drugs.”

The results for nine of the 10 patients reported in the paper suggest that memory loss may be reversed, and improvement sustained with this therapeutic program, said Bredesen. “This is the first successful demonstration,” he noted, but he cautioned that the results need to be replicated. “The current, anecdotal results require a larger trial, not only to confirm or refute the results reported here, but also to address key questions raised, such as the degree of improvement that can be achieved routinely, how late in the course of cognitive decline reversal can be effected, whether such an approach may be effective in patients with familial Alzheimer’s disease, and last, how long improvement can be sustained,” he said.

Cognitive decline is a major concern of the aging population. Already, Alzheimer’s disease affects approximately 5.4 million Americans and 30 million people globally. Without effective prevention and treatment, the prospects for the future are bleak. By 2050, it’s estimated that 160 million people globally will have the disease, including 13 million Americans, leading to potential bankruptcy of the Medicare system. Unlike several other chronic illnesses, Alzheimer’s disease is on the rise—recent estimates suggest that AD has become the third leading cause of death in the United States behind cardiovascular disease and cancer.

(Image: Corbis)

Study links physical activity in older adults to brain white-matter integrity

Like everything else in the body, the white-matter fibers that allow communication between brain regions also decline with age. In a new study, researchers found a strong association between the structural integrity of these white-matter tracts and an older person’s level of daily activity – not just the degree to which he or she engaged in moderate or vigorous exercise, but also whether the person was sedentary the rest of the time.

The study, reported in the journal PLOS ONE, tracked physical activity in 88 healthy but “low-fit” participants aged 60 to 78. The participants agreed to wear accelerometers during most of their waking hours over the course of a week, and also submitted to brain imaging.

“To our knowledge, this is the first study of its kind that uses an objective measure of physical activity along with multiple measures of brain structure,” said University of Illinois postdoctoral researcher Agnieszka Burzynska, who conducted the research with U. of I. Beckman Institute director Arthur Kramer and kinesiology and community health professor Edward McAuley.

Most studies ask subjects to describe how much physical activity they get, which is subjective and imprecise, Burzynska said. The accelerometer continuously tracks a person’s movement, “so it’s not what they say they do or what they think they do, but we have measured what they are actually doing,” she said.

The researchers assumed that participants’ activity levels over a week accurately reflected their overall engagement, or lack of engagement, in physical activity.

The study also relied on two types of brain imaging. The first, diffusion tensor imaging, offers insight into the structural integrity of a tissue by revealing how water is diffused in the tissue. The second method looks for age-related changes in white matter, called lesions. Roughly 95 percent of adults aged 65 and older have such lesions, Burzynska said. While they are a normal part of aging, their early onset or rapid accumulation may spell trouble, she said.

The team found that the brains of older adults who regularly engaged in moderate-to-vigorous exercise generally “showed less of the white-matter lesions,” Burzynska said.

The association between physical activity and white-matter structural integrity was region-specific, the researchers reported. Older adults who engaged more often in light physical activity had greater structural integrity in the white-matter tracts of the temporal lobes, which lie behind the ears and play a key role in memory, language, and the processing of visual and auditory information.

In contrast, those who spent more time sitting had lower structural integrity in the white-matter tracts connecting the hippocampus, “a structure crucial for learning and memory,” Burzynska said.

“This relationship between the integrity of tracts connecting the hippocampus and sedentariness is significant even when we control for age, gender and aerobic fitness,” she said. “It suggests that the physiological effect of sitting too much, even if you still exercise at the end of the day for half an hour, will have a detrimental effect on your brain.”

The findings suggest that engaging in physical activity and avoiding a sedentary lifestyle are both important for brain health in older age, Burzynska said.

“We hope that this will encourage people to take better care of their brains by being more active,” she said.