Can drinking coffee really improve your memory? Source: http://upload.wikimedia.org/wikipedia/commons/0 /06/Latte_art.jpg.
We all turn to coffee to pull us through late nights and the subsequent early mornings. Although caffeine has long been known to benefit alertness and short-term memory, recent research suggests that consuming caffeine after studying can also improve long-term memory.
Scientists led by Daniel Borota at John Hopkins University used “old-similar-new” judgment tests to determine that post-studying caffeine consumption can enhance memory consolidation.
In the experiment, 160 “caffeine-naive” participants were randomly given either a 200 mg dose of caffeine or a placebo control. Before administering the treatment, researchers presented subjects with a series of images; after 24 hours, researchers evaluated participants’ recognition by asking them to categorize images in a second set as targets (present in the first set of images), foils (not present in the first set of images), or lures (an image similar to but not the same as a target image).
In addition, researchers also took salivary samples at baseline before caffeine consumption and one, three, and 24 hours after caffeine consumption to determine the amount of caffeine metabolites remaining in the body. Caffeine concentration (µg/mL) increased dramatically in the 200 mg caffeine group at one and three hour intervals but returned to baseline levels after 24 hours.
Of all the subjects, those who took the 200 mg dose of caffeine had a higher lure discrimination index (LDI) and were more likely to distinguish a lure from a target than those who took the placebo. The relationship between caffeine concentration found in the subject’s saliva and the LDI resulted in an inverted quadratic curve. However, the groups revealed similar rates of correctly labeling images as targets or foils.
Researchers also determined that participants, who got less than 500 mg caffeine a week, required at least 200 mg of caffeine to experience the positive impact on memory consolidation. Those who received treatments of 100 mg of caffeine displayed similar results to the placebo group, while those taking 300 mg treatments of caffeine had LDI similar to that of the 200 mg treatment group.
Scientists believe that the next steps entail exploring how caffeine enhances long-term memory consolidation, a mechanism that remains uncertain for researchers. Borota and his team proposed several possible explanations including caffeine’s effects on the adenosine A1 receptor-rich, CA-2 regions of the hippocampus associated with long-term memory or its ability to block adenosine, which inhibits norepinephrine, a neurotransmitter linked to “pattern separation.”
For the increasingly health-conscious debating the benefits and risks associated with caffeine, this recent finding may be the tipping factor in their decision.
References:
1. D., Borota, et al., Post-study caffeine administration enhances memory consolidation in humans, Nature Neuro., 17, 2 (2014).