How memory meets perception during naturalistic scene understanding
As we navigate our visual world, what we see is seamlessly integrated with our memory of the broader environment. One long-standing puzzle in neuroscience is how perceptual and mnemonic systems – which are topographically distinct in the brain – interface to give rise to memory-guided visual experience. In this talk, I will present a series of studies using head-mounted virtual reality and fMRI to explore this question. First, we investigated the neural basis of scene perception and memory using fine-grained individual-subject fMRI. To our surprise, this analysis revealed a new network of brain areas that collectively bridge the scene perception and spatial memory systems of the human brain, the “place memory network” (Steel et al., Nat Coms, In Press). Specifically, we reveal three areas, each lying immediately anterior to a region of the scene perception network in posterior cerebral cortex, that selectively activate when recalling familiar real-world locations. Despite their close proximity to the scene-perception areas, network analyses show that these regions constitute a distinct functional network that interfaces with memory systems during naturalistic scene understanding. We hypothesize that these regions may provide remembered, contextual representations to support ongoing perception. In a second study, we use head-mounted virtual reality (VR) and behavior to test whether memory for a broad spatial environment, in fact, impacts ongoing scene perception in behavior. Using a priming paradigm, we show that a briefly presented scene view reinstates associated views of the panoramic environment, facilitating subsequent perception. Together, these studies illuminate how perceptual and mnemonic systems interact during naturalistic visual experience, and point to a new mechanistic step for understanding how the brain implements memory-guided visual behaviors in posterior cerebral cortex.