Coffee a memory enhancing drug, say boffins
Nurse, bring the caffeine drip, stat!
That staple of the IT industry everywhere, caffeine, is an aid to long-term memory, according to researchers from Johns Hopkins University.
In their study (abstract in Nature Neuroscience here), the researchers claim that theirs is the first study to demonstrate that caffeine has a direct impact on long-term memory.
The researchers used image recall as the basis of their work. As assistant professor of neurobiology and behaviour from the university Michael Yassa explained to the Australian Broadcasting Corporation's AM program:
“We showed them pictures on a computer screen and we asked them to make a simple decision whether these pictures were indoor pictures or outdoor pictures. It didn't really matter what the picture was or what they said, we just wanted to get them engaged in a task and sort of encode these images.
“We wanted them to learn these images without actually telling them it is going to be a memory test afterwards and then we either gave them a caffeine pill, 200 milligrams of caffeine, or a placebo and we sent them on their merry way.”
The researchers then gave their subjects a “surprise test” the next day. The two groups were tested on their recall of images from the first test. As the university's release states, “On the test, some of the visuals were the same as those from the day before, some were new additions, and some were similar but not the same. More members of the caffeine group were able to correctly identify the new images as 'similar' to previously viewed images rather than erroneously citing them as the same.”
The university says the “pattern separation” aspect of the test – using new images that nearly matched images from the first test – provided confirmation of the caffeine effect.
This study goes against the grain, in as much as previous studies have failed to identify a memory boost from caffeine. The researchers claim their study design has helped them make their discovery.
“Almost all prior studies administered caffeine before the study session, so if there is an enhancement, it's not clear if it's due to caffeine's effects on attention, vigilance, focus, or other factors,” Yassa said. “By administering caffeine after the experiment, we rule out all of these effects and make sure that if there is an enhancement, it's due to memory and nothing else.”
In other coffee-related good news, the most recent science on the stuff debunks the dearly-held myth that coffee causes dehydration. As explained at The Conversation here, a study in PLOSE ONE finds the diuretic effects of caffeine are less than the amount of water you drink with moderate coffee consumption. ®