Abstract
Functional imaging studies in human reliably identify a trio of scene-selective regions, one on each of the lateral (occipital place area, OPA), ventral (parahippocampal place araea, PPA) and medial (retrosplenial complex, RSC) cortical surfaces. Whilst the basic selectivity, and more recently retinotopic organization of OPA and PPA are relatively well understood, much less is known about the medial scene-selective area. Here, using fMRI, we combine detailed mapping of both population receptive fields (pRF) and category-selectivity, with independently acquired resting-state functional connectivity data, to examine retinotopic sensitivity within medial scene-selective cortex across a large number of participants. Consistent with previous work, we identify a medial scene-selective area, which was largely contained within the posterior bank of the parieto-occipital sulcus (POS) and did not extend into restrosplenial cortex, suggesting the use of RSC as a label for this region is potentially misleading. Interestingly, this same region was identifiable solely on the basis of responses to our retinotopic mapping stimuli with a striking degree of spatial consistency across participants. Our pRF analyses of this region not only demonstrate a high degree of retinotopic sensitivity, but also, highlight a significant contralateral visual field bias, coupled with very large receptive fields. Unlike, its scene-selective counterparts OPA and PPA, this medial scene-selective region did not show a consistent bias to either the lower or upper visual fields, respectively. The contralateral representation within this region was also confirmed through functional connectivity patterns observed in our independent resting-state data. Further, this medial scene-selective area appears to show greater connectivity at rest with anterior portions of ventral PPA than lateral OPA, despite lacking the upper visual field bias exhibited by PPA. Taken together, the retinotopic profile of medial scene-selective cortex suggests a prominent role in mediating scene related visual information between lateral OPA and ventral PPA.
Meeting abstract presented at VSS 2016