Consistent brain activity key to good memory

Consistent brain activity key to good memory
A sensor strapped on a soldier's head to test the brain's well-being. Constant activity is key to keeping the brain ticking

A new study has suggested that people would remember specific information such as faces or words better if the pattern of brain activity remains consistent every time the information is studied.




Russell Poldrack of University of Texas and his colleagues challenged the long-held belief that people retain information more effectively when they study it several times under different contexts and, thus, give their brains multiple cues to remember it.



“This helps us begin to understand what makes for effective studying. Sometimes we study and remember things, sometimes we don’t and this helps explain why,” said Mr. Poldrack.



The research represented the first time scientists have analyzed human memory by examining the pattern of activity across many different parts of the image called voxels. The new technique allows them to probe more deeply into the relationship between the mind and the brain.



“The question is how practice makes perfect. If you precisely reactivate the same pattern each time, then you are going to remember better,” said Gui Xue of the University of Southern California.



The researchers conducted three studies at Beijing Normal University in which subjects were shown different sets of photographs or words multiple times in different orders.



The scientists recorded subjects’ brain activity while they studied the material. They were asked to recall or recognize those items between 30 minutes and six hours later, in order to test the decades-old “encoding variability theory.” That theory suggested people would remember something more effectively if they study it at different times in different contexts than if they review it several times in one sitting.



Based on that theory, the researchers predicted subjects would retain memories of the photos or words more effectively if their brains were activated in different ways while studying that information multiple times.



Instead, the scientists found the subjects’ memories were better when their pattern of brain activity was more similar across different study episodes.



The findings were published in the journal Science.

Poor lifestyle 'behind cancer rise'

Poor lifestyle 'behind cancer rise'

NEW YORK: Cancers linked to unhealthy lifestyles are "one of the biggest challenges facing the world", an expert has said.




The rise in cancer linked to poor diet and a lack of exercise poses as much of a problem in the 21st Century as providing access to clean water did in the 19th Century, he said.



And Professor Martin Wiseman, medical and scientific adviser for the World Cancer Research Fund (WCRF), warned that millions of people around the world face an early death from the disease.



While the increase in many cancers is linked to the fact people are living longer, around 80,000 cases could be prevented every year in the UK if people ate better, kept to a healthy weight and exercised.



Around one in three of the most common cancers in high-income countries and about one in four in medium and low income countries could be stopped if people led healthier lives, estimates suggest.



According to the United Nations, the number of deaths from cancer worldwide is set to double by 2030.



And global cases of cancer have risen dramatically in the last 30 years, from 6.3 million cases in 1980 to 8.1 million in 1990 and 11.3 million in 2007.



But Prof Wiseman said this doubling was not inevitable and more should be done to prevent lifestyle cancers.



He was speaking ahead of the WCRF's international scientific conference in London, which will hear from speakers from the World Health Organisation and the International Agency for Research on Cancer.



Estimates are that a quarter of all cancer deaths are caused by unhealthy living and obesity. Cancers which are particularly affected by lifestyle include those of the bowel, stomach, mouth, foodpipe and breast.