People who drink coffee, will swear by its 'wake-me-up' benefits, but here's another information that's going to make coffee-addicts smile. According to researchers of John Hopkins University, the stimulant has one more benefit - it serves to wake up or enhance certain parts of the memory.

A study led by Michael Yassa, assistant professor of psychological and brain sciences in the Krieger School of Arts and Sciences at Johns Hopkins, and his team of scientists, claim that caffeine enhances certain memories up to at least 24 hours after its consumption. The research has been published in the journal Nature Neuroscience.

The double-blin trial comprised of giving the participants either a placebo or a 200-milligram caffeine tablet (or the equivalent amount of caffeine that would be found in 2-3 cups of coffee or about 2-3 8.4 oz cans of Red Bull) five minutes after they were shown series of images. Salivary samples of the participants were taken before they consumed the pill, and one, three and 24 hours after they consumed the pill.

The following day, the participants were shown a new set of images, which were mixed with the images shown the day before. The participants who took the caffeine pill were able to somewhat recognize the new set of images and say they were "similar" to the ones shown the day before and not erroneously identify them as the "same" images shown on the day before.

The difference between two similar but not identical items, called pattern separation, reflects a deeper level of memory retention, the researchers said.

"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," said Yassa. "We report for the first time a specific effect of caffeine on reducing forgetting over 24 hours."

"If we used a standard recognition memory task without these tricky similar items, we would have found no effect of caffeine," Yassa said. "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."

This is a breakthrough discovery as to date,  the few studies that have been done on caffeine's relation to memory, the general consensus was that caffeine has little or no effect on long-term memory retention.

The latest research probably could pinpoint the benefit of caffeine on memory retention because in prior experiments, the participants took the caffeine pills only after they had viewed and attempted to memorize the images, whereas in the latest research, the participants were given the pill after they had seen the images.

"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. 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," said Yassa.

However, there is still a lot of study that needs to be done to determine the true benefits of caffeine on memory retention.

"The next step for us is to figure out the brain mechanisms underlying this enhancement," he said. "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."

The latest study was funded by the National Institute on Aging as well as the National Science Foundation.