A pill-size dosage of caffeine taken a short time period after a learning session may enhance memory performance in people, reports a study published online this week in the journal Nature Neuroscience.
Daniel Borota and colleagues asked over 100 participants to identify pictured objects as either outdoor or indoor items. Shortly after this reporting period, they received either 200 mg of caffeine or placebo pills. When the participants returned a day later, they were shown some of the same pictures along with random new images and similar-looking new images. They were asked to categorize each picture as ‘old’, ‘new’ or ‘similar to original pictures’. Though both the placebo and caffeine pill groups were able to correctly identify pictures as ‘new’ or ‘old’, those who had taken caffeine were more accurate at distinguishing ‘similar’ pictures from the original ones, while those who received placebo incorrectly identified these ‘similar’ pictures as the ‘old’ originals. This caffeine-induced improvement in memory performance in recognizing similar images was not seen with smaller doses of caffeine or when caffeine was given one hour before the picture identification test.