The study – funded by Barry Callebaut and published inPhysiology and Behavior– investigated the effects of flavonol-rich on the functioning of spatial working memory. The research team, from Swinburne University, Australia, reported that 30 days supplementation with a high-flavanol chocolate drink did not affect behavioural measures of accuracy and reaction time; however, a number of brain areas were found to be significantly improved in terms of memory encoding, working memory hold period, and retrieval.
“In the absence of significant behavioural effects, these differences in brain activation can be interpreted as evidence of increased neural efficiency in spatial working memory function associated with chronic cocoa flavanol consumption,” said the research team, led by David Camfield of Swinburne.
"This is the first time that science has positively linked consumption of high flavanol cocoa and chocolate products from Barry Callebaut to improved brain performance,” said Hans Vriens, chief innovation officer at Barry Callebaut.
“When consumed regularly, the brain is able to complete memory tasks with less effort," he added.
Sixty-three volunteers aged between 40 and 65 given a daily chocolate drink over the 30 period of the randomised, controlled, double-blind trial.
Participants were divided up into three test groups, with each group consuming a chocolate drink containing a different amount cocoa flavanols – the first group received a drink containing 10 grams of dark high-flavanol chocolate (corresponding to 500 mg cocoa flavanols), the second group received a drink which contained 10 grams of conventional dark chocolate (250 mg of cocoa flavanols), whilst the third group received 10 grams of dark chocolate that contained only a few cocoa flavanols.
Camfield and his team used tasks that assess spatial working memory to measure human brain activity. In addition, and in order to compare brain activities, on the first and on the 30th day computer-tomography (CT) brain scans of the test subjects were made while participants solved the special memory tasks.
Camfield and his colleagues found no differences between the various groups in the accuracy or the reaction times of the test subjects in solving the task.
However they said the results of the CT scan revealed that the brains of individuals who consumed the cocoa drink with a medium or a high proportion of cocoa flavanols were less strained by the tasks the than those in the control group without cocoa flavanols.
This could mean that the higher flavanol chocolate lowered stress levels in the brain after consumption and allowed the test subjects to achieve the same performance with lower resource usage, suggested the authors.
Source: Physiology & Behavior
Volume 105, Issue 4, Pages 948–957, doi: 10.1016/j.physbeh.2011.11.013,
“Steady state visually evoked potential (SSVEP) topography changes associated with cocoa flavanol consumption”
Authors: D.A. Camfield, A. Scholey, A. Pipingas, R. Silberstein, M. Kras, K. Nolidin, K. Wesnes, M. Pase, C. Stough