Caffeine can improve attention and focus, we've known for a while. It also enhances working memory (short term, in the moment). Caffeine's effects on long-term memory, though, if any, aren't well established.

A study published yesterday in the journal Nature Neuroscience gets into that in a unique way, looking at caffeine's effect on memory consolidation. Dr. Michael Yassa, an assistant professor of psychological and brain sciences at Johns Hopkins University, explains:

Basically Yassa's research team gave people 100 to 300 milligrams of caffeine after looking at some images. The next day, those who got 200 or 300 milligrams of caffeine remembered the images better than people who took a placebo.

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

"We conclude that caffeine enhances consolidation of long-term memories in humans," the researchers wrote.

How much caffeine should I be drinking? Here's how the dosing looked:

It is interesting that the placebo had a bigger effect than the small dose of caffeine.

Two hundred milligrams is about half of a Starbucks venti coffee. Imagine how good your memory could be if you had seven or eight of those. Just kidding, I think. I'm not recommending that.