Posts tagged executive function
Articles and news from the latest research reports.
Similar but different: new discovery for degenerative disease
Progressive Supranuclear palsy (PSP) and Parkinson’s Disease (PD) have overlapping symptoms but remain difficult to distinguish.
However, a first ever paper on the topic published in the Journal of Neuropsychology (British Psychological Society publication) now suggests that people with PSP experience more severe and extensive cognitive impairments than those with PD early on.
The study indicates that patients with PSP experience more severe and extensive impairments in higher order functions such as planning, abstract thinking, memory retrieval than those with PD.
Lead researcher Dr Young-Eun Claire Lee said the two conditions are so similar that in some cases, patients with PSP often go undiagnosed for the main part of their illness.
“PD and PSP are the two of the most common forms of neurodegenerative diseases resulting in loss of balance and deterioration in mobility,” said Dr Lee.
“Telling these differences apart can be challenging because most patients with PSP do not develop distinctive symptoms such as paralysis or weakness of the eye muscles and episodes of frequent falling until later stages,” she said.
While the study sample was small, the results indicate that cognitive profiles may aid differential diagnosis in earlier stages. PSP claimed the life of musician/actor Dudley Moore.
There are no current treatments for PSP.
Strong working memory put brakes on problematic drug use
Adolescents with strong working memory are better equipped to escape early drug experimentation without progressing into substance abuse issues, says a University of Oregon researcher.
Most important in the picture is executive attention, a component of working memory that involves a person’s ability to focus on a task and ignore distractions while processing relevant goal-oriented information, says Atika Khurana, a professor in the Department of Counseling Psychology and Human Services.
Khurana, also a member of the UO’s Prevention Science Institute, is lead author of a study online ahead of print in the quarterly journal Development and Psychopathology. The findings, drawn from a long-term study of 382 adolescents in a mostly at-risk urban population, provide a rare, early view of adolescents’ entry into the use of alcohol, tobacco and marijuana.
Khurana collaborated with researchers at the University of Pennsylvania and Children’s Hospital of Philadelphia. They focused on 11- to 13-year-old children as they began to explore risky and sensation-seeking experiences that often mark the road to independence and adulthood. Previous studies generally have relied on adult recall of when individuals began experimenting, with early drug use thought to be a marker of later substance abuse problems.
"Not all forms of early drug use are problematic," Khurana said. "There could be some individuals who start early, experiment and then stop. And there are some who could start early and go on into a progressive trajectory of continued drug use. We wanted to know what separates the two?"
During four assessments, participants provided self-reports of drug use in the previous 30 days. Four working memory tests also were conducted: Corsi block tapping, in which subjects viewed identical blocks that lit up randomly on a screen and tapped each box in reverse order of the lighting sequence; a digit-span test where numbers shown are to be repeated in reverse order; a letter two-back test, in which subjects identify specific letters in time-sensitive sequences; and a spatial working-memory task where hidden tokens must be found quickly within sets of four to eight randomly positioned boxes on a computer screen.
The pattern that emerged was that early drug experimentation more likely to lead into progressive drug use among young people whose impulsive tendencies aren’t kept in check by strong working memory ability. Later assessments of the participants, who have now reached late adolescence, are being analyzed, but it appears that the compulsive progression, not just the experimentation, of drug use is likely to lead to disorder, Khurana said.
"Prefrontal regions of the brain can apply the brakes or exert top-down control over impulsive, or reward seeking urges," Khurana said. "By its nature, greater executive attention enables one to be less impulsive in one’s decisions and actions because you are focused and able to control impulses generated by events around you. What we found is that if teens are performing poorly on working memory tasks that tap into executive attention, they are more likely to engage in impulsive drug-use behaviors."
The findings suggest new approaches for early intervention since weaknesses in executive functioning often underlie self-control issues in children as young as 3 years old, she said. A family environment strong in structured routines and cognitive-stimulation could strengthen working memory skills, she said.
For older children, interventions could be built around activities that encourage social competence and problem solving skills in combination with cognition-building efforts to increase self-control and working memory. The latter allows people to temporarily store, organize and manipulate mental information and is vital for evaluating consequences of decisions.
"We need to compensate for the weakness that exists, before drug experimentation starts to help prevent the negative spiral of drug abuse," Khurana said.
This Is Your Brain on Snacks—Brain Stimulation Affects Craving and Consumption
Magnetic stimulation of a brain area involved in “executive function” affects cravings for and consumption of calorie-dense snack foods, reports a study in the September issue of Psychosomatic Medicine: Journal of Biobehavioral Medicine, the official journal of the American Psychosomatic Society. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.
After stimulation of the dorsolateral prefrontal cortex (DLPFC), young women experience increased cravings for high-calorie snacks—and eat more of those foods when given the opportunity, according to the study by researchers at University of Waterloo, Ont., Canada. “These findings shed a light on the role of the DLPFC in food cravings (specifically reward anticipation), the consumption of appealing high caloric foods, and the relation between self-control and food consumption,” the researchers write. The senior author was Peter Hall, PhD.
Brain Stimulation Affects Cravings and Consumption for ‘Appetitive’ Snacks
The study included 21 healthy young women, selected because they reported strong and frequent cravings for chocolate and potato chips. Such “appetitive,” calorie-dense snack foods are often implicated in the development of obesity.
The women were shown pictures of these foods to stimulate cravings. The researchers then applied a type of magnetic stimulation, called continuous theta-burst stimulation, to decrease activity in the DLPFC. Previous studies have suggested that DLPFC activity plays a role in regulating food cravings.
After theta-burst stimulation, the women reported stronger food cravings—specifically for “appetitive” milk chocolate and potato chips. During a subsequent “taste test,” they consumed more of these foods, rather than alternative, less-appetitive foods (dark chocolate and soda crackers).
Stimulation to weaken DLPFC activity was also associated with lower performance on a test of inhibitory control strength (the Stroop test). Decreased DLPFC activity appeared to be associated with increased “reward sensitivity”—it made the participants “more sensitive to the rewarding properties of palatable high caloric foods,” the researchers write.
Weak Executive Function May Contribute to Obesity Risk
The results highlight the role of executive function in governing “dietary self-restraint,” the researchers believe. Executive function, which involves the DLPFC, refers to a set of cognitive functions that enable “top-down” control of action, emotion, and thought.
At the “basic neurobiological level,” the study provides direct evidence that the DLPFC is involved in one specific aspect of food cravings: reward anticipation. People with weak executive function may lack the dietary self-control necessary to regulate snack food consumption in “the modern obesogenic environment.” Faced with constant cues and opportunities to consume energy-dense foods, such individuals may be more likely to become overweight or obese.
The results suggest that interventions aimed at enhancing or preserving DLPFC function may help to prevent obesity and related diseases. In conditions such as type 2 diabetes, where healthy dietary habits are essential for effective disease control, “Interventions focused on enhancing DLPFC activity, through aerobic exercise or other means, may result in increased dietary self-control and subsequently improve disease management,” Dr Hall and coauthors add.
(Source: newswise.com)
Train your heart to protect your mind
Exercising to improve our cardiovascular strength may protect us from cognitive impairment as we age, according to a new study by researchers at the University of Montreal and its affiliated Institut universitaire de gératrie de Montréal Research Centre. “Our body’s arteries stiffen with age, and the vessel hardening is believed to begin in the aorta, the main vessel coming out of the heart, before reaching the brain. Indeed, the hardening may contribute to cognitive changes that occur during a similar time frame,” explained Claudine Gauthier, first author of the study. “We found that older adults whose aortas were in a better condition and who had greater aerobic fitness performed better on a cognitive test. We therefore think that the preservation of vessel elasticity may be one of the mechanisms that enables exercise to slow cognitive aging.”
The researchers worked with 31 young people between the ages of 18 and 30 and 54 older participants aged between 55 and 75. This enabled the team to compare the older participants within their peer group and against the younger group who obviously have not begun the aging processes in question. None of the participants had physical or mental health issues that might influence the study outcome. Their fitness was tested by exhausting the participants on a workout machine and determining their maximum oxygen intake over a 30 second period. Their cognitive abilities were assessed with the Stroop task. The Stroop task is a scientifically validated test that involves asking someone to identify the ink colour of a colour word that is printed in a different colour (e.g. the word red could be printed in blue ink and the correct answer would be blue). A person who is able to correctly name the colour of the word without being distracted by the reflex to read it has greater cognitive agility.
The participants undertook three MRI scans: one to evaluate the blood flow to the brain, one to measure their brain activity as they performed the Stroop task, and one to actually look at the physical state of their aorta. The researchers were interested in the brain’s blood flow, as poorer cardiovascular health is associated with a faster pulse wave,at each heartbeat which in turn could cause damage to the brain’s smaller blood vessels. “This is first study to use MRI to examine participants in this way,” Gauthier said. “It enabled us to find even subtle effects in this healthy population, which suggests that other researchers could adapt our test to study vascular-cognitive associations within less healthy and clinical populations.”
The results demonstrated age-related declines in executive function, aortic elasticity and cardiorespiratory fitness, a link between vascular health and brain function, and a positive association between aerobic fitness and brain function. “The link between fitness and brain function may be mediated through preserved cerebrovascular reactivity in periventricular watershed areas that are also associated with cardiorespiratory fitness,” Gauthier said. “Although the impact of fitness on cerebral vasculature may however involve other, more complex mechanisms, overall these results support the hypothesis that lifestyle helps maintain the elasticity of arteries, thereby preventing downstream cerebrovascular damage and resulting in preserved cognitive abilities in later life.”
Upfront and personal: Scientists model human reasoning in the brain’s prefrontal cortex
Located at the forward end of the brain’s frontal lobe, the mammalian prefrontal cortex (PFC) is the seat of many of our most unique cognitive abilities – collectively referred to as executive function – including planning, decision-making, and coordinating thoughts and actions with internal goals. That said, perhaps its most important attribute – one that is apparently unique to H. sapiens – is reasoning which, based on Bayesian, or probabilistic, inference, mitigates uncertainty by informing adaptive behavior. While the structural details of this remarkable process have historically remained elusive, scientists at Institut National de la Santé et de la Recherche Médicale, Paris, and Ecole Normale Supérieure, Paris and Université Pierre et Marie Curie, Paris have recently employed computational modeling and neuroimaging to show that the human prefrontal cortex involves two interactive reasoning pathways that embody hypothesis testing for evaluating, accepting and rejecting behavioral strategies. More specifically, their model describes behavior guided by reason in the form of an online algorithm combining Bayesian inference applied to multiple stored strategies with hypothesis testing that can update these strategies. In addition – as proposed in a previous work – the scientists conclude that since the frontopolar cortex (FPC), located in the anterior-most portion of the frontal lobes, is human-specific and is a key component in executive function decision-making, the ability to make inferences on concurrent strategies and decide to switch directly to one of these alternative strategies is unique to humans as well.
Prof. Etienne Koechlin discussed the paper that he, Dr. Maël Donoso and Dr. Anne G. E. Collins published in Science.
Study shows puzzle games can improve mental flexibility
A recent study by Nanyang Technological University (NTU) scientists showed that adults who played the physics-based puzzle video game Cut the Rope regularly, for as little as an hour a day, had improved executive functions.
The executive functions in your brain are important for making decisions in everyday life when you have to deal with sudden changes in your environment – better known as thinking on your feet. An example would be when the traffic light turns amber and a driver has to decide in an instant if he will be able to brake in time or if it is safer to travel across the junction/intersection.
The video game study by Assistant Professor Michael D. Patterson and his PhD student Mr Adam Oei, tested four different games for the mobile platform, as their previous research had shown that different games trained different skills.
The games varied in their genres, which included a first person shooter (Modern Combat); arcade (Fruit Ninja); real-time strategy (StarFront Collision); and a complex puzzle (Cut the Rope).
NTU undergraduates, who were non-gamers, were then selected to play an hour a day, 5 days a week on their iPhone or iPod Touch. This video game training lasted for 4 weeks, a total of 20 hours.
Prof Patterson said students who played Cut the Rope, showed significant improvement on executive function tasks while no significant improvements were observed in those playing the other three games.
“This finding is important because previously, no video games have demonstrated this type of broad improvement to executive functions, which are important for general intelligence, dealing with new situations and managing multitasking,” said Prof Patterson, an expert in the psychology of video games.
“This indicates that while some games may help to improve mental abilities, not all games give you the same effect. To improve the specific ability you are looking for, you need to play the right game,” added Mr Oei.
The abilities tested in this study included how fast the players can switch tasks (an indicator of mental flexibility); how fast can the players adapt to a new situation instead of relying on the same strategy (the ability to inhibit prepotent or predominant responses); and how well they can focus on information while blocking out distractors or inappropriate responses (also known as the Flanker task in cognitive psychology).
Prof Patterson said the reason Cut the Rope improved executive function in their players was probably due to the game’s unique puzzle design. Strategies which worked for earlier levels would not work in later levels, and regularly forced the players to think creatively and try alternate solutions. This is unlike most other video games which keep the same general mechanics and goals, and just speed up or increase the number of items to keep track of.
After 20 hours of game play, players of Cut the Rope could switch between tasks 33 per cent faster, were 30 per cent faster in adapting to new situations, and 60 per cent better in blocking out distractions and focusing on the tasks at hand than before training.
All three tests were done one week after the 52 students had finished playing their assigned game, to ensure that these were not temporary gains due to motivation or arousal effects.
The study will be published in the academic journal, Computers in Human Behavior, this August, but is available currently online. This is the first study that showed broad transfer to several different executive functions, further providing evidence the video games can be effective in training human cognition.
“This result could have implications in many areas such as educational, occupational and rehabilitative settings,” Prof Patterson said.
“In future, with more studies, we will be able to know what type of games improves specific abilities, and prescribe games that will benefit people aside from just being entertainment.”
In their previous study published last year in PloS One, a top academic journal, Prof Patterson and Mr Oei studied the effects mobile gaming had on 75 NTU undergraduates.
The non-gamers were instructed to play one of the following games: “match three” game Bejeweled, virtual life simulation game The Sims, and action shooter Modern Combat.
The study findings showed that adults who play action games improved their ability to track multiple objects in a short span of time, useful when driving during a busy rush hour; while other games improved the participants’ ability for visual search tasks, useful when picking out an item from a large supermarket.
Moving forward, the Prof Patterson is keen to look at whether there is any improvement from playing such games in experienced adult gamers and how much improvement one can make through playing games.
Exposure to TV Violence Related to Irregular Attention and Brain Structure
Young adult men who watched more violence on television showed indications of less mature brain development and poorer executive functioning, according to the results of an Indiana University School of Medicine study published online in the journal Brain and Cognition.
The researchers used psychological testing and MRI scans to measure mental abilities and volume of brain regions in 65 healthy males with normal IQ between the age of 18 and 29, specifically chosen because they were not frequent video game players.
Lead author Tom A. Hummer, Ph.D., assistant research professor in the IU Department of Psychiatry, said the young men provided estimates of their television viewing over the past year and then kept a detailed diary of their TV viewing for a week. Participants also completed a series of psychological tests measuring inhibitory control, attention and memory. At the conclusion, MRI scans were used to measure brain structure.
Executive function is the broad ability to formulate plans, make decisions, reason and problem-solve, regulate attention, and inhibit behavior in order to achieve goals.
"We found that the more violent TV viewing a participant reported, the worse they performed on tasks of attention and cognitive control," Dr. Hummer said. "On the other hand, the overall amount of TV watched was not related to performance on any executive function tests."
Dr. Hummer noted that these executive functioning abilities can be important for controlling impulsive behaviors, including aggression. “The worry is that more impulsivity does not mix well with the behaviors modeled in violent programming.”
Tests that measured working memory, another subtype of executive functioning, were not found to be related to overall or violent TV viewing.
Comparing TV habits to brain images also produced results that Dr. Hummer and colleagues believe are significant.
"When we looked at the brain scans of young men with higher violent television exposure, there was less volume of white matter connecting the frontal and parietal lobes, which can be a sign of less maturity in brain development," he said.
White matter is tissue in the brain that insulates nerve fibers connecting different brain regions, making functioning more efficient. In typical development, the amount or volume of white matter increases as the brain makes more connections until about age 30, improving communication between regions of the brain. Connections between the frontal and parietal lobes are thought to be especially important for executive functioning.
"The take-home message from this study is the finding of a relationship between how much violent television we watch and important aspects of brain functioning like controlled attention and inhibition," Dr. Hummer said.
Dr. Hummer cautions that more research is needed to better understand the study findings.
"With this study we could not isolate whether people with poor executive function are drawn to programs with more violence or if the content of the TV viewing is responsible for affecting the brain’s development over a period of time," Dr. Hummer said. "Additional longitudinal work is necessary to resolve whether individuals with poor executive function and slower white matter growth are more drawn to violent programming or if exposure to media violence modifies development of cognitive control," Dr. Hummer said.
(Source: newswise.com)
Brain size matters when it comes to animal self-control
Chimpanzees may throw tantrums like toddlers, but their total brain size suggests they have more self-control than, say, a gerbil or fox squirrel, according to a new study of 36 species of mammals and birds ranging from orangutans to zebra finches.
Scientists at Duke University, UC Berkeley, Stanford, Yale and more than two-dozen other research institutions collaborated on this first large-scale investigation into the evolution of self-control, defined in the study as the ability to inhibit powerful but ultimately counter-productive behavior. They found that the species with the largest brain volume – not volume relative to body size – showed superior cognitive powers in a series of food-foraging experiments.
Moreover, animals with the most varied diets showed the most self-restraint, according to the study published in the journal of the Proceedings of the National Academy of Sciences.
“The study levels the playing field on the question of animal intelligence,” said UC Berkeley psychologist Lucia Jacobs, a co-author of this study and of its precursor, a 2012 paper in the journal, Animal Cognition.
This latest study was led by evolutionary anthropologists Evan MacLean, Brian Hare and Charles Nunn of Duke University. The findings challenge prevailing assumptions that “relative” brain size is a more accurate predictor of intelligence than “absolute” brain size. One possibility, they posited, is that “as brains get larger, the total number of neurons increases and brains tend to become more modularized, perhaps facilitating the evolution of new cognitive networks.”
While participating researchers all performed the same series of experiments, they did so on their own turf and on their own animal subjects. Data was provided on bonobos, chimpanzees, gorillas, olive baboons, stump-tailed macaques, golden snub-nosed monkeys, brown, red-bellied and aye-aye lemurs, coyotes, dogs, gray wolves, Asian elephants, domestic pigeons, orange-winged amazons, Eurasian jays, western scrub jay, zebra finches and swamp sparrows.
Food inside a tube used as bait
In one experiment, creatures large and small were tested to see if they would advance toward a clear cylinder visibly containing food – showing a lack of self-restraint – after they had been trained to access the food through a side opening in an opaque cylinder. Large-brained primates such as gorillas quickly navigated their way to the treat or “bait.” Smaller-brained animals did so with mixed results.
Jacobs and UC Berkeley doctoral student Mikel Delgado contributed the only rodent data in the study, putting some of the campus’s fox squirrels and some Mongolian gerbils in their lab through food-foraging tasks.
Mixed results on campus squirrels’ self-restraint
In the case of the fox squirrels, the red-hued, bushy-tailed critters watched as the food was placed in a side opening of an opaque cylinder. Once they demonstrated a familiarity with the location of the opening, the food was moved to a transparent cylinder and the real test began. If the squirrels lunged directly at the food inside the bottle, they had failed to inhibit their response. But if they used the side entrance, the move was deemed a success.
“About half of the squirrels and gerbils did well and inhibited the direct approach in more than seven out of 10 trials,” Delgado said. “The rest didn’t do so well.”
In a second test, three cups (A, B and C) were placed in a row on their sides so the animals could see which one contained food. It was usually cup A. The cups were then turned upside down so the “baited” cup could no longer be seen. If the squirrels touched the cup with the food three times in a row, they graduated to the next round. This time, the food was moved from cup A to cup C at the other end of the row.
“The question was, would they approach cup A, where they had originally learned the food was placed, or could they update this learned response to get the food from a new location?” Delgado said. “The squirrels and gerbils tended to go to the original place they had been trained to get food, showing a failure to inhibit what they originally learned.” Click here for video showing other animals doing the cup test.
“It might be that a squirrel’s success in life is affected the same way as in people,” Jacobs said. “By its ability to slow down and think a bit before it snatches at a reward.”
(Source: newscenter.berkeley.edu)
Musicians have sharper minds are able to pick up mistakes and fix them quicker than the rest of us, according to new research.
The study, by researchers at the University of St Andrews, suggests that musical activity could protect against decline in mental abilities through age or illness.
The work, published in the journal Neuropsychologia, extends previous findings that mental abilities are positively related to musical skills. The researchers say that the latest findings demonstrate the potential for ‘far reaching benefits’ of musical activity on mental and physical well-being.
The study was led by St Andrews psychologist Dr Ines Jentzsch, who compared the cognitive ability of amateur musicians versus non-musicians in performing simple mental tasks.
The most striking difference she found lay in the musicians’ ability to recognise and correct mistakes. Not only that, but they responded faster than those with little or no musical training, with no loss in accuracy. This is perhaps not surprising since musicians learn to be constantly aware of their performance, but to not be overly affected by mistakes.
Dr Jentzsch, a Reader in the University’s School of Psychology and Neuroscience, commented, “Our study shows that even moderate levels of musical activity can benefit brain functioning.
“Our findings could have important implications as the processes involved are amongst the first to be affected by aging, as well as a number of mental illnesses such as depression. The research suggests that musical activity could be used as an effective intervention to slow, stop or even reverse age- or illness-related decline in mental functioning.”
The study compared groups of amateur musicians with varying levels of time they had spent in practicing their instrument to a non-musician control group. They then measured each group’s behavioural and brain responses to simple mental tests.
The results showed that playing a musical instrument, even at moderate levels, improves the ability to monitor our behavior for errors and adjust subsequent responses more effectively when needed.
Dr Jentzsch, herself a keen pianist, continued, “Musical activity cannot only immensely enrich our lives but the associated benefits for our physical and mental functioning could be even more far-reaching than proposed in our and previous research.
“Music plays an important role in virtually all societies. Nevertheless, in times of economic hardship, funds for music education are often amongst the first to be cut.
“We strongly encourage political decision makers to reconsider funding cuts for arts education and to increase public spending for music tuition.
“In addition, adults who have never played an instrument or felt too old to learn should be encouraged to take up music - it’s never too late.”
Vascular brain injury greater risk factor than amyloid plaques in cognitive aging
Vascular brain injury from conditions such as high blood pressure and stroke are greater risk factors for cognitive impairment among non-demented older people than is the deposition of the amyloid plaques in the brain that long have been implicated in conditions such as Alzheimer’s disease, a study by researchers at the Alzheimer’s Disease Research Center at UC Davis has found.
Published online early today in JAMA Neurology (formerly Archives of Neurology), the study found that vascular brain injury had by far the greatest influence across a range of cognitive domains, including higher-level thinking and the forgetfulness of mild cognitive decline.
The researchers also sought to determine whether there was a correlation between vascular brain injury and the deposition of beta amyloid (Αβ) plaques, thought to be an early and important marker of Alzheimer’s disease, said Bruce Reed, associate director of the UC Davis Alzheimer’s Disease Research Center in Martinez, Calif. They also sought to decipher what effect each has on memory and executive functioning.
“We looked at two questions,” said Reed, professor in the Department of Neurology at UC Davis. “The first question was whether those two pathologies correlate to each other, and the simple answer is ‘no.’ Earlier research, conducted in animals, has suggested that having a stroke causes more beta amyloid deposition in the brain. If that were the case, people who had more vascular brain injury should have higher levels of beta amyloid. We found no evidence to support that.”
"The second,” Reed continued, “was whether higher levels of cerebrovascular disease or amyloid plaques have a greater impact on cognitive function in older, non-demented adults. Half of the study participants had abnormal levels of beta amyloid and half vascular brain injury, or infarcts. It was really very clear that the amyloid had very little effect, but the vascular brain injury had distinctly negative effects.”
“The more vascular brain injury the participants had, the worse their memory and the worse their executive function – their ability to organize and problem solve,” Reed said.
The research was conducted in 61 male and female study participants who ranged in age from 65 to 90 years old, with an average age of 78. Thirty of the participants were clinically “normal,” 24 were cognitively impaired and seven were diagnosed with dementia, based on cognitive testing. The participants had been recruited from Northern California between 2007 to 2012.
The study participants underwent magnetic resonance imaging (MRI) ― to measure vascular brain injury ― and positron emission tomography (PET) scans to measure beta amyloid deposition: markers of the two most common pathologies that affect the aging brain. Vascular brain injury appears as brain infarcts and “white matter hyperintensities” in MRI scans, areas of the brain that appear bright white.
The study found that both memory and executive function correlated negatively with brain infarcts, especially infarcts in cortical and sub-cortical gray matter. Although infarcts were common in this group, the infarcts varied greatly in size and location, and many had been clinically silent. The level of amyloid in the brain did not correlate with either changes in memory or executive function, and there was no evidence that amyloid interacted with infarcts to impair thinking.
Reed said the study is important because there’s an enormous amount of interest in detecting Alzheimer’s disease at its earliest point, before an individual exhibits clinical symptoms. It’s possible to conduct a brain scan and detect beta amyloid in the brain, and that is a very new development, he said.
“The use of this diagnostic tool will become reasonably widely available within the next couple of years, so doctors will be able to detect whether an older person has abnormal levels of beta amyloid in the brain. So it’s very important to understand the meaning of a finding of beta amyloid deposition,” Reed said.
“What this study says is that doctors should think about this in a little more complicated way. They should not forget about cerebrovascular disease, which is also very common in this age group and could also cause cognitive problems. Even if a person has amyloid plaques, those plaques may not be the cause of their mild cognitive symptoms.”
(Source: ucdmc.ucdavis.edu)