Parietal-driven visual working memory representation in occipito-temporal cortex

Human fMRI studies have documented extensively that the content of visual working memory (VWM) can be reliably decoded from fMRI voxel response patterns during the delay period in both the occipito-temporal cortex (OTC), including early visual areas (EVC), and the posterior parietal cortex (PPC).1-4 Further work has revealed that VWM signal in OTC is largely sustained by feedback from associative areas such as prefrontal cortex (PFC) and PPC.4-9 It is unclear, however, if feedback during VWM simply restores sensory representations initially formed in OTC or if it can reshape the representational content of OTC during VWM delay. Taking advantage of a recent finding showing that object representational geometry differs between OTC and PPC in perception,10 here we find that, during VWM delay, the object representational geometry in OTC becomes more aligned with that of PPC during perception than with itself during perception. This finding supports the role of feedback in shaping the content of VWM in OTC, with the VWM content of OTC more determined by information retained in PPC than by the sensory information initially encoded in OTC.

Automated summary

Human fMRI studies have shown that the content of visual working memory (VWM) can be decoded from the response patterns in various brain regions. The VWM signal is sustained by feedback from associative areas, and during the delay period, the representational geometry in the occipito-temporal cortex (OTC) becomes aligned with that of the posterior parietal cortex (PPC) rather than its own perception.