Abstract
Working memory (WM) is the ability to maintain and manipulate a limited amount of information over a short time. Previous research has shown that noisy activation patterns in retinotopic cortex during a WM delay period encode both the memorized feature and the uncertainty regarding how accurately it is represented (Li et al., 2021; Geurts et al, 2022), and that participants can accurately introspect which of several representations they can report most precisely (Fougnie et al, 2012; Suchow et al, 2017; Li & Sprague, 2023). However, how participants read out the relative uncertainty for multiple WM representations from neural activity patterns remains unclear. Here, we acquired fMRI data during a memory guided saccade task in which participants remembered 1 or 2 locations over a 12 s delay period and reported the location of one item with a saccade. Extending our previous study (Li & Sprague, 2023), on each trial, at the end of the delay period participants were either instructed to report a cued item or choose the item they believed they remembered best with a saccade. After the memory report, participants reported their uncertainty about the reported location by adjusting the extent of an arc (as in Li et al, 2021). Results showed that when participants were asked to report their best-remembered item, recall error and uncertainty were both lower compared to randomly-cued trials, consistent with accurate introspection of the relative quality of multiple WM representations. Moreover, delay-period WM representations reconstructed from activation patterns in extrastriate cortex were stronger for memory items reported on “report best” trials as compared to the non-reported item. These findings suggest that participants can simultaneously compare and report the quality of multiple remembered locations, and demonstrate that these reports are based on the quality of neural WM representations in retinotopic cortex.