Tag Archives: Memory
Could Herpes Virus Affect Memory in Older Adults?
Chronic infection with cold sores may affect thinking, especially in sedentary folks, study suggests
WebMD News from HealthDay
By Amy Norton
HealthDay Reporter
MONDAY, March 25 (HealthDay News) — Older adults who harbor certain infections, such as the herpes cold sore virus, may have poorer thinking and memory abilities than their peers, a new study suggests.
Researchers found that of more than 1,600 older adults, those with signs of chronic infection with herpes simplex and certain other viruses and bacteria scored lower on standard tests of mental skills.
But the findings, published in the March 26 issue of Neurology, do not prove the infections are to blame.
“They could just be bystanders,” said lead researcher Dr. Mira Katan, a neurologist with Columbia University College of Physicians and Surgeons in New York City.
“We can’t make any definite conclusions about causality,” Katan said. “At this stage, you can just say there’s an association.”
Still, it’s an “interesting” association that needs further study, she said.
Many people carry herpes simplex virus, or HSV. One form, HSV-1, usually causes cold sores around the mouth, while HSV-2 is the main cause of genital herpes. Once a person is infected with either form of HSV, the virus remains dormant in the body’s nerve cells and can be reactivated repeatedly.
HSV can also move to any part of the body, including the brain, and for several decades, some researchers have speculated that chronic HSV infection might contribute to dementia — possibly by causing persistent inflammation.
In the new study, Katan’s team used blood samples from 1,625 older adults — average age 69 — to look for indicators of chronic infection with a few common pathogens: HSV and another virus in the herpes family called cytomegalovirus, which usually causes no symptoms; C. pneumoniae, a bacterium that causes respiratory infections; and H. pylori, a stomach-dwelling bacterium that can cause ulcers.
On average, the greater their “infection burden,” the worse the older adults performed on a standard test of thinking and memory, the study found.
That was true even when the researchers weighed other factors that affect older adults’ mental sharpness, including education, smoking, heart disease and diabetes.
But the study hinted that exercise might play a protective role. The research team found that infection “burden” was related to mental impairment only among sedentary people — and not those who said they got some exercise.
However, that too needs to be studied further, the team noted.
Katan said that infection with the viruses, rather than the two bacteria, seemed to play a greater role in mental decline. Overall, 23 percent of the study participants had signs of mental impairment at the study’s start; the odds of impairment were 2.5 times higher among people who carried all three viruses — HSV 1 and 2, and cytomegalovirus — than for people who carried only one virus.
Lighter Sleep May Dull Memory Skills in Seniors
SUNDAY Jan. 27, 2013 — It’s no secret that your memory skills decline as you get older, making it harder for you to pick up new tasks or remember where you put your keys.
Now, a new study suggests that the culprit lurks in the lighter sleep that accompanies aging.
Researchers found that older people get less deep sleep than their younger counterparts, and this appears to be directly linked to less reliable memory. Older people were more than 50 percent less able to remember new things after sleeping than young people.
The study, however, isn’t definitive. It was fairly small, mostly looked at women and examined only one kind of memory — the ability to remember pairs of words. Its authors, however, said the findings are strong enough to justify paying more attention to helping older people sleep better.
“In the young adults, sleep was doing a really good job at not letting those memories dissolve,” explained study author Matthew Walker, an associate professor of neuroscience and psychology at the University of California at Berkeley. “Sleep just wasn’t doing that same kind of job in the elderly. As a consequence, they had far more severe forgetting, and a significant reason was because of the quality of their deep sleep.”
In the study, researchers gave memory tests to 18 younger people (with an average age of 20) and 15 older people (with an average age of 72). The participants were then monitored as they slept, and took the memory test again.
After making statistical adjustments, the researchers found that although the older and younger people were about the same when it came to remembering things before sleeping, their ability to remember diverged afterwards.
The researchers said the older adults scored 55 percent less on the memory test after sleeping. They would not discuss the actual scores, saying they would be misleading from a statistical point of view.
The memory differences between the older and younger adults would probably be “noticeable in situations that require consistently high performance,” said Dr. Phyllis Zee, director of the Sleep Disorders Center at Northwestern University.
So what’s going on? The researchers blame it on less sleep in the older people.
“It’s not just important to sleep before learning,” Walker said. “You have to sleep after learning to consolidate those new memories and make long-term memories.”
The researchers believe that older people aren’t remembering as much because their sleep isn’t as deep as that of the younger people. The good news is that better sleep could make a difference, he said.
Paul Reber, an associate professor of psychology at Northwestern University who studies sleep, said there’s reason to support a focus on deep sleep in particular. “It could be the case that as we age, our sleep gets disrupted more — by aches, pains and [the] bladder — and this is affecting our daily memory function,” he said.
The story appears online Jan. 27 in the journal Nature Neuroscience.
More information
For more about memory, try the U.S. National Library of Medicine.
Posted: January 2013
Study Ties Obesity-Related Gene to Weaker Memory
FRIDAY Nov. 9, 2012 — In middle-aged people, a link may exist between weakened memory and genetic traits associated with obesity, raising the possibility that extra pounds change how our brains work, a new study suggests.
Researchers found the link between genes and memory in whites but not in blacks.
The research “could be useful in identifying people who may need more help with declining cognition,” said John Speakman, a professor at the Institute of Biological and Environmental Sciences at the University of Aberdeen in Scotland, who is familiar with the findings.
Although some people believe obesity is purely a failure of individual will, scientists think genetic makeup has a lot to do with the propensity to gain extra pounds. Studies of twins and families suggest that genes account for about 65 percent of variance in body weight, Speakman said.
The new study focuses on four genetic traits related to a gene that’s thought to play a role in obesity. Researchers looked for signs of the traits among nearly 8,400 white and 2,100 black people aged 45 to 64.
They found signs of a link between problems being able to remember words and two of the genetic traits. The connection held up even after the researchers adjusted their results so they wouldn’t be thrown off by factors like large or small numbers of people who were of certain ages, genders, levels of obesity and education levels.
What’s going on? It’s not clear. Speakman said it’s possible that the gene may affect both weight and memory.
“On the other hand, they could be linked because of negative impacts of obesity on memory function, or vice versa,” he said. “The data don’t allow us to see if that might be the case.”
Dr. Michael Schwartz, director of the Diabetes and Obesity Center of Excellence at the University of Washington, in Seattle, pointed out that the connection held up even when the researchers tried to remove any influence of weight levels.
“That suggests that it was present regardless of whether individuals were lean or obese,” said Schwartz, who is familiar with the study findings.
What about the apparent difference between blacks and whites in the research? Schwartz said limitations of the study may have prevented it from detecting similarities between the groups even though they exist.
In the big picture, he said, the research raises questions about these genetic variations and their effects on how the brain works. That can lead to future understanding of cause and effect and tell us how it all matters, he said.
The study, which appears online Nov. 7 in the journal Neurology, was supported by the U.S. National Institutes of Health. Although the study found an association among memory problems, genetic traits and obesity, it did not prove a cause-and-effect relationship.
More information
For more about obesity, try the U.S. National Library of Medicine.
Posted: November 2012
Ecstasy Pills Cause Memory Problems
Taking 10 or More Pills a Year Linked to Immediate and Short-Term Memory Problems
July 27, 2012 — People who use the club drug ecstasy (MDMA) can develop memory problems, a new study shows.
In the study, new ecstasy users who took 10 or more ecstasy pills during their first year showed problems with their immediate and short-term memory.
The researchers say the memory problems may not be immediately apparent. Ecstasy users may not notice the problems until permanent damage has been done. The memory issues are associated with damage of an area of the brain called the hippocampus, which is responsible for memory.
The study compared 23 new users of the drug to 43 people who didn’t use any illicit drugs besides cannabis. On average, study participants who used ecstasy took 33 pills over the course of one year.
“Given the specific memory impairments, our findings may raise concerns in regard to MDMA use, even in recreational amounts over a relatively short time period,” says study researcher Daniel Wagner, in an email. He is a psychologist at the Klinik fur Psychiatrie und Psychotherapie in Cologne, Germany.
The study is published in the journal Addiction.
Ecstasy Risks Go Beyond Memory Problems
“People often take ecstasy in combination with other substances, including alcohol and cocaine. And they often take it at parties, dances, and raves where they may become dehydrated and at risk for all sorts of physiological health problems,” says Bruce Goldman, director of substance abuse services at the Zucker Hillside Hospital in Glen Oaks, N.Y.
And that’s not all. “Ecstasy makes you feel all lovey-dovey. And this can lead to impaired judgment about sex,” he says. In these scenarios, ecstasy puts people at risk for sexually transmitted diseases including HIV, the virus that causes AIDS.
Ecstasy is also highly addictive, Goldman says. Research from the National Institute on Drug Abuse showed that 43% of teens and young adults who use ecstasy are addicted. “Use of ecstasy is dangerous even if it’s done occasionally.”
Harris Stratyner, PhD, agrees. He is the vice president of the New York Clinical Regional Services at Caron Treatment Centers in New York City. He has seen how this drug can destroy lives.
“Ecstasy is an extremely dangerous hallucinogenic drug and we have known that for years,” he says. “Even just going to a rave and taking one ecstasy pill puts you at risk for becoming overheated.” Severe overheating can damage vital organs or lead to death.
“Using as little as 10 pills of ecstasy a year can have a deleterious effect on short-term memory and may even have a greater effect on all cognitive function,” he says.
Get This Much Sleep for a Sharp Memory
7 Hours Optimal; Too Much or Too Little Sleep May Lead to Memory Problems
July 16, 2012 — Getting a recommended seven hours of sleep a night may help women keep their memory sharp, suggests a new analysis of data from the Nurses’ Health Study.
The study found that women who slept five hours or less on average per day had lower scores on standard memory tests than those who slept seven hours, reports Elizabeth Devore, ScD, of Brigham and Women’s Hospital in Boston.
Similarly, women who slept nine or more hours on average per night had lower memory scores than those who slept seven hours a night, Devore tells WebMD.
“Women who got too little or too much sleep had the memories of women about two years [their senior],” she says.
The link between sleep duration and memory held true both in mid-life and later life, Devore says.
The findings were presented in Vancouver at the Alzheimer’s Association International Conference.
Many Don’t Get Enough Sleep
A recent CDC study found that more than 40 million workers get less than six hours of sleep per night.
Devore notes that growing evidence suggests that getting more or less than the recommended seven hours per day of sleep is associated with an increased risk of heart disease and type 2 diabetes.
“Since both heart disease and diabetes have been linked to an increased probability of having [memory] problems, we hypothesized that sleep duration may also influence memory,” she says.
So the researchers examined data for more than 15,000 participants in the Nurses’ Health Study. The women answered questions about how many hours they slept a night both in 1986 (when they were aged 40 to 65) and in 2000 (when they were aged 54 to 79).
Then, between 1995 and 2000, when the women were aged 70 or older, they took a series of memory tests. Follow-up memory tests were conducted every other year for six years.
“Interestingly, women whose sleep changed by two or more hours per day on average from mid- to later life had worse memory than those with no change in sleep duration, independent of their initial sleep duration,” Devore says.
Dean M. Hartley, PhD, director of science initiatives at the Alzheimer’s Association, points out that the study doesn’t show cause and effect, only that there is an association between sleep and memory.
But other studies support a link, too. For example, researchers at Beth Israel Deaconess Medical Center found that a good night’s sleep triggers changes in the brain that help to improve memory.
“We’ve had inklings of a link. And this is a very dynamic study with a large number of participants. Together with its other health benefits, including its role in protecting against heart disease and diabetes, this is yet another reason to get a good night’s sleep,” Hartley says.
Devore says she’s hopeful that the work could eventually lead to new strategies to protect against impairment of memory and thinking abilities and also Alzheimer’s disease.
Researchers are also trying to figure out whether sleep affects brain chemicals that may protect against dementia.
