Cover legend: The phase relationship as a function of time between a prefrontal and a parietal local field potential (8–25 Hz) during a visual working memory task. This example illustrates a flip in the phase relationship from anti-phase to in-phase. The background is a schematic of the phase relationships between prefrontal and posterior parietal cortex. For more details, see the article by Dotson et al. (pages 13600–13613).