January 13, 2014
Study Finds Link Between Caffeine And Long-Term Memory Enhancement
[ Watch the Video: Memory Enhancement From Coffee Consumption ]
redOrbit Staff & Wire Reports - Your Universe Online
Michael Yassa, assistant professor of psychological and brain sciences, and his colleagues report in their study that caffeine has a positive impact on long-term recollection in humans, enhancing some memories for roughly one full day after consumption.
“We've always known that caffeine has cognitive-enhancing effects, but its particular effects on strengthening memories and making them resistant to forgetting has never been examined in detail in humans,” Yassa explained. “We report for the first time a specific effect of caffeine on reducing forgetting over 24 hours.”
In a double-blind trial, the study authors recruited participants who did not eat or drink products that contained caffeine on a regular basis. They had the subjects study a series of images, and then randomly provided them with either a 200mg caffeine tablet or a placebo five minutes later. Salivary samples were taken to measure the caffeine levels of the subject before they took the pills, then again one hour, three hours and 24 hours later.
The following day, both groups were quizzed to see how well they could recognize images they had been exposed during the previous day’s study session, the researchers said. One of the pictures included on the test was the same as the previous day, some were similar but not exactly identical, and some were entirely new.
[ Watch the Video: Coffee Time? How Caffeine Can Boost Your Memory ]
“More members of the caffeine group were able to correctly identify the new images as ‘similar’ to previously viewed images versus erroneously citing them as the same,” the university said in a statement. The investigators noted that this ability is known as pattern separation, and it is indicative of a higher level of memory retention.
“If we used a standard recognition memory task without these tricky similar items, we would have found no effect of caffeine,” Yassa added. “However, using these items requires the brain to make a more difficult discrimination – what we call pattern separation, which seems to be the process that is enhanced by caffeine in our case.”
Only a handful of previous studies have examined caffeine’s impact on long-term memory, the researchers said, and most of those had found that the substance had little to no effect on retention. The difference between this study and previous papers is that the participants only consumed caffeine tablets after first looking at and attempting to memorize the various images they would later be asked to identify.
“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, who has since relocated his lab to the University of California-Irvine, 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.”
“The next step for us is to figure out the brain mechanisms underlying this enhancement,” he added. “We can use brain-imaging techniques to address these questions. We also know that caffeine is associated with healthy longevity and may have some protective effects from cognitive decline like Alzheimer's disease. These are certainly important questions for the future.”