Cognitive performance includes executive functions like cognitive flexibility. Executive functions include mental functions, which are used to steer behavior in relation to conditions of the environment: setting targets, planning, deciding on priorities, controlling impulses, regulation of emotions, regulation of attention, targeting and sequencing of actions, motor functions, observation of consequences of actions and self-correction. Cognitive flexibility “has been described as the mental ability to switch between thinking about two different concepts, and to think about multiple concepts” (according to Wikipedia).
The brain is built up from last three months of pregnancy to the third decade. Building up the brain is not just growing of the brain structure (for which DHA is needed), but also cross-linking brain cells by branching out of neurons and axons, which is improved in the presence of EPA and DHA (Innis, 2014). Even with a completed structure, the brain will need DHA from the blood to maintain the structure, which is harder with lower levels of DHA in the blood (Bradbury, 2011). Moreover, complex brain functions depend on the circulation of the brain, with both EPA and DHA being important modulators of brain circulation (Kiso, 2011). For complex brain functions inflammatory processes also play a role. Inflammatory processes develop less, and are resolved faster, in the presence of high levels of EPA and DHA; here cytokines like resolvins, neuroprotectins and maresins are involved (Janssen & Kiliaan, 2014). Although the interplay of all these mechanisms is not yet fully understood, it has become clear that EPA and DHA play a major role for higher brain functions.