University of Pittsburgh researchers led by
Rajesh Narendran of the Department of Radiology tested the effects of a supplement providing 930 milligrams eicosapentaenoic acid (EPA) and 750 milligrams docosahexaenoic acid (DHA) in 11 men and women between the ages of 18 and 25. Evaluation of working memory (via an "n-back test"), positron emission tomography (PET) imaging of the brain and tests for red blood cell fatty acid levels were conducted before and after the six month treatment period.
Participants experienced an increase in plasma omega-3 fatty acid levels and improvement in working memory at the end of six months. "What was particularly interesting about the presupplementation n-back test was that it correlated positively with plasma omega-3,"observed Bita Moghaddam, whose lab conducted the research. "This means that the omega-3s they were getting from their diet already positively correlated with their working memory."
"Before seeing this data, I would have said it was impossible to move young healthy individuals above their cognitive best," he remarked. "We found that members of this population can enhance their working memory performance even further, despite their already being at the top of their cognitive game."
Although the researchers had suggested increases in dopamine storage and a protein involved in decision making in a particular area of the brain as mechanisms supporting omega-3's effect on cognitive function, PET scan results failed to support the hypothesis. "It is really interesting that diets enriched with omega-3 fatty acid can enhance cognition in highly functional young individuals," Dr Narendran commented. "Nevertheless, it was a bit disappointing that our imaging studies were unable to clarify the mechanisms by which it enhances working memory."