Abstract
Transsaccadic perception (TSP) requires the retention, updating, and integration / comparison of visual information obtained before and after a saccade. Based on our earlier psychophysical and TMS studies, we hypothesized that TSP taps into frontoparietal mechanisms for spatial updating, and that low level location/feature integration might occur through feedback to occipital cortex, whereas higher level interactions might occur through lateral dorsoventral connectivity or prefrontal convergence (e.g., Prime et al., Philos. Trans. R. Soc. Lond., B, Biol. Sci. 2011). Here, we set about localizing these interactions using an fMRI adaptation paradigm. We found evidence for transsaccadic orientation perception in supramarginal gyrus (SMG) (Dunkley et al., Cortex 2016). We then extended SMG’s role to updating object orientation for grasp, engaging a functional network including the frontal eye fields and parietal grasp areas (Balaretu et al., J. Neurosci. 2021). However, when we applied this approach to spatial frequency, we found saccade-feature interactions in dorsal occipital cortex (Baltaretu et al., Sci. Rep. 2021). Most recently, we employed a task involving transsaccadic discrimination of object orientation versus shape (Baltaretu et al., bioRxiv 2021). Graph theory analysis revealed a bilateral dorsal functional module extending across parietofrontal cortex, whereas saccade-feature interactions fell within two lateralized occipital modules that rejoined in the presence of saccades. Overall, our data are consistent with the notion that TSP is a cortical network phenomenon that includes interactions between saccade signals and spatial features (location, orientation) in parietal cortex versus identity-related features (spatial frequency, shape) in occipital cortex.