When we hold two things in memory, we might exchange a feature of one object with the other. For example, if I saw an apple on the table, and an orange on the shelf, I might swap them round. In this set of experiments (Tabi et al Sci Rep 2026), we developed a task that tests whether this is really the case. It turns out it’s not straightforward! The feature swap may be asymmetrical. In other words, sometimes we remember both fruit on the table, or both on the shelf. This tells us about the architecture of working memory, and rules out some previously proposed models.