By Martha Kerr

CHICAGO (Reuters Health) - In older individuals, exercise is associated with an increase in the number of large-diameter vessels in the cerebral region of the brain and with an increase in blood flow in the three major cerebral arteries, researchers announced at the annual meeting of the Radiological Society of North America, which is being held here this week.

As the investigators noted, narrowing and loss of small vessels may contribute to cognitive decline. This area of the brain controls functions that include consciousness, memory, initiation of activity, emotional response, language and word associations.

LONDON (Reuters) - A slow, chronic reduction of blood sugar to the brain could trigger some forms of Alzheimer’s disease, U.S. researchers said on Wednesday.

The study of human and mice brains suggests a reduction of blood flow deprives energy to the brain, setting off a process that ultimately produces the sticky clumps of protein researchers believe is a cause of the disease, they said.

The finding could lead to strategies such as exercise, reducing cholesterol and managing blood pressure to keep Alzheimer’s at bay, Robert Vassar and colleagues at Northwestern University’s Feinberg School of Medicine in Chicago reported.

By Amy Norton

NEW YORK (Reuters Health) - Older adults might want to take an interest in their grandchildren’s’ video games, if early research on the brain benefits of gaming is correct.

In a study of 40 adults in their 60s and 70s, researchers found that those who learned to play a strategy-heavy video game improved their scores on a number of tests of cognitive function.

Men and women who trained in the game for about a month showed gains in tests of memory, reasoning and the ability to “multi-task.”
The findings suggest that video games that keep players “on their toes” might help older adults keep their brains sharp, the researchers report in the journal Psychology and Aging.

WASHINGTON (Reuters) - An insomnia drug that helps the body produce more of the sleep hormone melatonin may improve sleep for jet-lagged travelers and shift workers, researchers reported on Monday.

Maryland-based Vanda Pharmaceuticals Inc. reported on two studies of its drug tasimelteon, also known as VEC-162, that showed it helped patients sleep longer and more deeply than a placebo.

They said that people with so-called circadian rhythm disorders could be helped. These disorders are common causes of insomnia that affect millions of people whose activities are out of sync with their internal body clocks.

By Will Dunham

WASHINGTON (Reuters) - Spending a lot of time watching TV, playing video games and surfing the Web makes children more prone to a range of health problems including obesity and smoking, U.S. researchers said on Tuesday.

U.S. National Institutes of Health, Yale University and the California Pacific Medical Center experts analyzed 173 studies done since 1980 in one of the most comprehensive assessments to date on how exposure to media sources impacts the physical health of children and adolescents.

SYDNEY (Reuters) - It seems a bad back might be the only thing that can stop the relentless spread of Australia’s poisonous cane toads, which are killing native animals as they hop across the nation, researchers say.

Australia’s army couldn’t stop the cane toads, which number around 200 million. Residents swinging golf clubs failed and so did a campaign to freeze them to death in refrigerators.

But now an Australian scientist says evolution has seen the biggest and fastest cane toads interbreed, resulting in arthritis and bad backs which could slow them down.