Researchers at University of Reading and the Peninsula Medical School in Plymouth, both in England, say the improvements emerging the third week continued throughout the 12-week study.

The study, scheduled to be published in Free Radical Biology and Medicine, says the ability of blueberry flavonoids -- in particular anthocyanins and flavanols -- induce memory improvements via a specific pathway in the hippocampus, the part of the brain that controls learning and memory.

"This study not only adds science to the claim that eating blueberries are good for you, it also provides support to a diet-based approach that could potentially be used to increase memory capacity and performance in the future," principal investigator Dr. Matt Whiteman of Peninsula Medical School said in a statement.

The enhancement of both short-term and long-term memory is controlled at the molecular level in neurons, the researchers say.

The research team was able to show that the ability of flavonoids to induce memory improvements are mediated by the activation of signaling proteins via a specific pathway in the hippocampus.