Flexible early prospection of potential behavior in working memory

For visual working memory to serve upcoming behavior, it is crucial that we prepare for the potential use of working-memory contents ahead of time. Recent studies have demonstrated how the prospection and planning for an upcoming manual action starts early after visual encoding, and occurs alongside visual retention. Here, we address whether such output planning in visual working memory flexibly adapts to different visual-motor mappings, and occurs even when an upcoming action will only potentially become relevant for behavior. Participants performed a visual-motor working memory task in which they remembered one or two visual items for later (potential) use. We tracked planning of upcoming behavior through contralateral attenuation of beta-band activity - a canonical motor-cortical EEG signature of manual-action planning. This revealed how action encoding and subsequent planning alongside visual working memory (1) reflects anticipated task demands rather than specific visual-motor mappings, (2) occurs even for actions that will only potentially become relevant for behavior, and (3) is associated with better performance for the encoded item, at the expense of performance to other working-memory content. This reveals how the potential prospective use of visual working memory content is flexibly planned early on, with consequences for later performance.