Neural Correlates of Interobserver Visual Congruency in Free-Viewing Condition

Dynamic visual scenes lead to varying consistency of observers' eye movements, reflecting one intrinsic characteristic of visual scenes, termed interobserver visual congruency (IOVC). However, the neural correlates underlying IOVC are largely unknown especially in the free-viewing condition. In this study, we explored the neural correlates of IOVC using functional magnetic resonance imaging (fMRI) and eye-tracking data acquired in a naturalistic paradigm. Specifically, we estimated IOVC of movie shots from eye-tracking data and then conducted two statistical analyses for functional inference, including a hypothesis-driven analyses [general linear model (GLM)] and a data-driven approach [intersubject correlation (ISC)]. The GLM analysis demonstrated that IOVC recruited two distinctive streams of neural systems. Specifically, neural activities in superior temporal gyrus, default mode network, and hippocampus were positively correlated with IOVC, whereas those in the primary and secondary visual cortices, as well as the dorsal attention network exhibited negative correlations. Further ISC analysis revealed that movie shots with higher IOVC evoked more synchronous brain activities in the primary auditory cortex, primary visual cortex, and superior parietal lobule compared to those shots with lower IOVC. This study provides some novel evidence of visual processing in the human brain in the free-viewing condition.