Effects of food energy on cognitive performance: no support from event-related potentials (yet?).

Several reviews of behavioural studies have concluded that some foods may have beneficial effects on cognitive performance. The present review summarises findings from studies using event-related potentials to investigate the food effects on brain activity underlying cognition. Despite initial positive indications from observational studies, subsequent studies with a within-subject design have not consistently confirmed these effects. This could be due to several factors, e.g. the use of attention tests (in contrast to memory tests employed in behavioural studies) and the lack of a control condition in some instances. Future studies could benefit from measuring cognitive performance with more difficult tests that tap into cognitive domains other than attention, using an appropriately controlled cross-over design, and a more systematic variation and complete description and characterisation of the food intervention.