Super supplement found to boost memory within 24 HOURS of taking it in breakthrough study

Previous research has found a link between caffeine intake and improved memory.

Researchers at Johns Hopkins University sought to confirm this association by giving respondents a caffeine tablet. Their results are published in the journal Nature Neuroscience.

They conducted a double-blind trial in which participants who did not regularly eat or drink caffeinated products received either a placebo or a 200-milligram caffeine tablet five minutes after studying a series of images.

Salivary samples were taken from the participants before they took the tablets to measure their caffeine levels. Samples were taken again one, three, and 24 hours afterwards.

The next day, both groups were tested on their ability to recognise images from the previous day's study session. On the test, some of the visuals were the same as those from the day before, some were new additions, and some were similar but not the same.

More members of the caffeine group were able to correctly identify the new images as "similar" to previously viewed images rather than erroneously citing them as the same.

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

The researchers concluded that "caffeine enhanced consolidation of long-term memories in humans".

Memory consolidation is the process of turning new memories into long-term memories, making them more resistant to interference and easier to retrieve.

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

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A separate study, published in Journal of Nutrition suggested coffee might also have longer-term effects on thinking skills.

Other studies are less convinced by this association. For example, a study published in Neuroscience & Biobehavioral Reviewsfound no consistent effect of caffeine across all types of memory.

Another study even suggests coffee impairs memory performance.

Researchers posit that caffeine blocks adenosine receptors, which prevents adenosine from stopping norepinephrine - a hormone that can have positive effects on memory.

Caffeine also increases serotonin and acetylcholine, which can help stimulate the brain and stabilise the blood-brain barrier.