A research suggests that caffeine intake boosts short-term memory that can last the whole day.

Researchers from John Hopkins University led by Michael Yassa, an assistant professor of psychological and brain sciences in JHU’s Krieger School of Arts and Sciences, are giving us another good reason to continue consuming caffeine.

“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 said in a press release. “We report for the first time a specific effect of caffeine on reducing forgetting over 24 hours.”

The researchers recruited unidentified number of individuals who are not regularly taking any form of caffeine. They took samples of their saliva to check their caffeine levels. Afterwards, they were asked to study a set of photos. Five minutes later, they were asked to drink either a 200mg caffeine tablet or a placebo. Then, samples were taken again after an hour, three hours, and 24 hours of intake.

The following day, both groups were asked to identify the set of photos they have previously studied. However, some of the photos in the set were new and some were modified, meaning they look similar but not identical.

Surprisingly, majority of the participants in the caffeine group were able to correctly recognize the altered images as only “similar” to the previous photo and not the same.

According to the researchers, that ability to identify the difference between two similar but not identical images reflects a deeper level of memory retention.

Yassa said in the press release, “If we used a standard recognition memory task without these tricky similar items, we would have found no effect of caffeine. 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.”

Though the result of the study seems promising, caffeine's effects on long-term memory had not been examined in detail. Considering all the studies done, the common judgment was that caffeine has little or no effect on long-term memory retention.

This study was published in the January 12 issue of Nature Neuroscience.