This Week in The Journal

Research consistently links alpha waves to working memory, revealing that these waves become more powerful when there is a higher working memory load or when distractors are anticipated.Previous work also suggests that inhibition from alpha waves shields working memory from competing stimuli, but how alpha waves do this remains unclear.To explore this, Zeng et al. assessed the spatiotemporal dynamics of alpha oscillations, which, according to the authors, researchers have not done before.By reanalyzing two openaccess EEG datasets of 180 people performing visual working memory tasks, the authors discovered that the direction alpha waves move plays different roles in working memory retention.As distractor load increased, forward-moving alpha power increased.Additionally, as memory set size increased, forward-moving alpha power increased, but backward-moving alpha power decreased.The authors also observed a lateralization effect, whereby the increases in forward-moving alpha power occurred in the brain hemisphere contralateral to the competing stimulus, while the decrease in backward-moving alpha power occurred in the brain hemisphere contralateral to the target stimulus.Altogether, forward-moving waves appear to be regulated by distractor load, while backward-moving waves are inversely modulated by memory targets.