The researchers measured the strength of nine muscle groups in the arms and legs of 970 dementia-free men and women 54 to 100 years old (their average age was around 80). They also tested the strength of study participants' breathing muscles.

During follow-up, which lasted about four years, 138 people developed Alzheimer's. These individuals were older and had worse mental function than the rest of the study participants. They also were weaker.

But even after the researchers adjusted for age and education level-which can influence Alzheimer's risk-they found that muscle strength had a strong influence on the risk of the disease. People who ranked in the top 10 percent for muscle strength were 61 percent less likely to develop Alzheimer's than the weakest 10 percent. Stronger people also showed a slower decline in their mental abilities over time.

The UCLA team worked with 24 neurologically normal volunteers between the ages of 55 and 78. Prior to the study, half the participants used the Internet daily, while the other half had very little experience. Age, educational level and gender were similar between the two groups.

The participants performed Web searches while undergoing functional magnetic resonance imaging (fMRI) scans, which recorded the subtle brain-circuitry changes experienced during this activity. This type of scan tracks brain activity by measuring the level of blood flow in the brain during cognitive tasks. While the study involves a small number of people and more research on this topic is needed, small study sizes are typical of fMRI-based research.

After the initial brain scan, subjects went home and conducted Internet searches for one hour a day for a total of seven days over a two-week period. These practice searches involved using the web to answer questions about various topics by exploring different websites and reading information. Participants then received a second brain scan using the same Internet simulation task, but with different topics.

The first scan of participants with little Internet experience showed brain activity in the regions controlling language, reading, memory and visual abilities. The second brain scan of these participants, conducted after the home practice searches, demonstrated activation of these same regions, but there was also activity in the middle frontal gyrus and inferior frontal gyrus – areas of the brain known to be important in working memory and decision-making.

Thus, after Internet training at home, participants with minimal online experience displayed brain activation patterns very similar to those seen in the group of savvy Internet users. "The results suggest that searching online may be a simple form of brain exercise that might be employed to enhance cognition in older adults," Teena D. Moody, the study's first author and UCLA researcher, said in a statement.

A report from King's College London suggests more than 115 million people across the globe will suffer from dementia by 2050.

This prediction is 10% more than previous figures published in 2005, driven mainly by new figures from South Asia and Latin America.

The Alzheimer's Society said the data showed the "scale of the challenge".

"The technology will provide the location of the individual wearing the shoes within 30 feet, anywhere on the planet," said Andrew Carle, an assistant professor at George Mason University who served as an advisor on the project.

"Sixty percent of individuals afflicted with Alzheimer's Disease will be involved in a 'critical wandering incident' at least once during the progression of the disease -- many more than once," he said Friday.

The shoes are being developed by GTX Corp., which makes miniaturized Global Positioning Satellite tracking and location-transmitting technology, and Aetrex Worldwide, a footwear manufacturer.

"Two weeks ago, Brooke Shields was forced to make a public disclosure about her mother, Teri Shields's health, when we learned that Mrs. Shields had been taken out of a care facility by a reporter and photographer working for the National Enquirer and I was told that the National Enquirer was going to print information about her condition and whereabouts," Shields's attorney, Gerald B. Lefcourt says in an exclusive statement to People.

"I am very pleased to report that [the] National Enquirer was prevailed upon not to publish a story. Further, it has or will be apologizing publicly. Finally, it has agreed to make a generous donation to further research on dementia and to encourage others to do so."

At the time of the incident, the actress said in a statement to People that she had been "alerted by Old Tappan Police that my mother had been signed out of the facility by two reporters of the National Enquirer ... who falsely claimed they were friends of hers." She added: "They then drove my 75-year-old mother around looking for a tabloid story. As anyone knows who has a parent who suffers from dementia or Alzheimer's, it is one of the most difficult experiences you can go through as a son or daughter. The idea that the National Enquirer took advantage of her state is reprehensible and disgusting."

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Shields's attorney Lefcourt tells People: "I am glad that Brooke Shields and her family can consider the matter now closed."