Memory responses in visual cortex track recall success after single-trial encoding

Classic models of episodic memory propose that retrieval relies on the reactivation of previous perceptual representations in sensory cortex, a phenomenon known as cortical reinstatement. Supporting this idea, visual memory retrieval has been shown to evoke activity patterns in visual areas similar to those during encoding. However, recent work suggests that memory responses systematically diverge from perceptual ones, challenging this idea. Critically, these studies have focused on highly trained memories, leaving open whether similar effects arise in more naturalistic, single-shot memory scenarios, which are hallmarks of episodic memory. Here, we used fMRI and population receptive field (pRF) modeling to test whether spatially tuned memory responses emerge in early visual cortex after a single encoding event. We scanned 19 participants with fMRI while testing them on their recognition and spatial recall of peripheral objects seen only once. We observed spatially tuned responses in early visual cortex during both recognition and recall, even though spatial location was never explicitly probed during recognition. These responses were better tuned for successfully remembered items, indicating a relationship between neural tuning and behavioral memory performance. Moreover, spatial tuning at encoding predicted subsequent memory: responses for subsequently remembered objects were stronger near the object location and suppressed elsewhere, relative to forgotten items. Taken together, our findings show that a single experience is sufficient to enable spatially tuned reactivation in early visual cortex when remembering an item. Further, our results indicate an important role, during both encoding and retrieval, for early visual cortex representations in successful episodic memory.