EPA supplements improve cognitive function and reduce brain strain

Omega 3 EPA: a valuable aid to brain health
Omega 3 supplements rich in EPA (eicosapentaenoic acid), in young subjects, increase cognitive performance and help the brain work with less effort. Those with DHA (docosahexaenoic acid) seem less efficient in enhancing neurocognitive performance.

This is reported in a study, published in the journal Human Psychopharmacology: Clinical and Experimental, carried out by researchers at Swinburne University of Technology in Hawthorn, Australia, with the aim of studying the action of Omega-3 supplements toward brain activity and cognitive abilities.

Omega-3 and cognitive function
DHA is a major constituent of nervous tissue, as one of the major components of the membranes of neurons. EPA, on the other hand, is found in low amounts in the brain. Both of these fatty acids are important for the development and function of the central nervous system. Several studies have confirmed that Omega-3s improve cognitive development in children and counteract neurodegenerative processes in the elderly. In particular, they affect memory, spatio-temporal orientation, attention, speech fluency and cognitive processing speed.

Results visible with MRI
The research involved 13 subjects with an average age of 24 years who were randomly given supplements containing either 417 mg DHA or 590 mg EPA for 30 days. After an interval period, subjects who had received the DHA-rich supplements received the EPA-rich ones, and vice versa, for another 30 days. Before and after each treatment, the young people underwent functional MRI, a technique for visualizing organ function. The researchers thus obtained a map of the brain areas activated during specific cognitive tests required to assess attention level and short-term memory.
The results showed that after EPA supplements, decreased activation of the left anterior cingulate cortex, the region of the brain responsible for cognitive functions such as decision making or impulse control, and increased activation of the precentral gyrus, the region involved in implementing corrective strategies. Also evident was the reduction in reaction time. With DHA-rich supplements there was an increase in functional activation in the precentral gyrus region, but no behavioral changes were visible . Among other things, the researchers saw that after both supplements, the ratio of arachidonic acid to EPA was reduced. For the scientists, neuronal efficiency reflects the relationship between cognitive performance and brain effort. Indeed, humans tend to modify their neuronal activity to maintain the level of acceptable cognitive performance.
Thus, measuring performance without considering the levels of brain activation may give inaccurate results, as happened in previous studies investigating the effects of supplements. The analyses showed that EPA and DHA are incorporated differently in cell membranes: the former is rapidly transformed into the phospholipid phosphatidylcholine by positioning itself in the outer side of the membrane, the latter is transformed into the phospholipid phosphatidylethanolamine by positioning itself in the inner side. Whether the change in cognitive activity is related to the insertion of these molecules into the membranes is not yet well understood.

EPA supplements are more effective than DHA supplements
Extending the theory of neuronal efficiency, according to which smarter people activate fewer nerve cells for problem solving, the study showed that as a result of EPA supplements, the brain works less and achieves better cognitive performance. In contrast, the increased functional activation and lack of improvement in reaction time and accuracy of cognitive performance following DHA supplementation suggests that this is ineffective. After all, however, as disputed by Harry Rice, of the Global Organization for EPA and DHA Omega-3, the two supplements were administered in different doses. The researchers pointed out, however, that in a study in 2010 by researchers at the University of Cincinnati, a similar dose of DHA increased brain activation during a test for visual attention.

Source: Isabelle Bauer, Matthew Hughes,Renee Rowsell, Robyn Cockerell,Andrew Pipingas, Sheila Crewther andDavid Crewther. "Omega-3 supplementation improves cognition and modifies brain activation in young adults," Human Psychopharmacology: Clinical and Experimental. Vol. 29, Issue 2, pages 133-144, March 2014