Neuroscientist and research leader Michael Yassa says consumed in moderate amounts, coffee could have beneficial effects for health. – AFP
People who had caffeine after looking at images apparently better at distinguishing them from similar ones the next day.
A CUP or two of coffee could boost the brain’s ability to store long-term memories, researchers in the United States claim.
People who had a shot of caffeine after looking at a series of pictures were better at distinguishing them from similar images in tests the next day, the scientists found.
The task gives a measure of how information is stored in the brain, which helps with a process called pattern separation which can be crucial in everyday situations.
Michael Yassa, a neuroscientist who led the study at Johns Hopkins University in Baltimore, said the ability to separate patterns was vital for discriminating between similar scenarios and experiences in life.
Writing in the journal Nature Neuroscience, Yassa described how 44 volunteers who were not heavy caffeine consumers and had abstained for at least a day were shown a rapid sequence of pictures on a computer screen.
When each image flashed up on the screen, the person watching had to say whether the object was normally found indoors or outside. At the end of the task, each volunteer was randomly assigned either a 200mg caffeine pill or a placebo. A typical cup of coffee contains around 150mg of caffeine.
The next day, the scientists brought the volunteers back. This time, the sequence of images included many they had seen the day before, but some were new and others were similar. The similar images varied in how close to the originals they were. Some showed the same object from a different angle, while others were a similar type of object, such as a different design of hammer from the one they had seen before.
For this part of the study, the volunteers had to say whether each image was new, old or similar to one they had seen. According to Yassa, the caffeine and placebo groups scored the same except when it came to spotting the similar images. In this task, the caffeine group scored around 10% higher, he said.
“What I’ve taken from this is that I should keep drinking my coffee,” Yassa told Britain’s the Guardian. “Our study suggests there’s a real learning and memory benefit. In moderate amounts, it could have beneficial effects for health.”
Yassa said it was unclear how caffeine might help the storage of memories, but one theory is that it leads to higher levels of a stress hormone called norepinephrine in the brain, which helps memories to be laid down.
Some scientists, however, say they need more evidence to believe the effect. George Kemenes, a neuroscientist who studies memory at Sussex University in south-east England, said the statistical techniques used in the paper were not good enough to prove the effect was real.
Jon Simons, who works on memory at Cambridge University, said the effect needed to be shown in a larger number of people. – Guardian News & Media