Incidental learning of predictive temporal context within cortical representations of visual shape

Objective:Incidental learning of spatiotemporal regularities and consistencies-also termed 'statistical learning'-may be important for discovering the causal principles governing the world. We studied statistical learning of temporal structure simultaneously at two time-scales: the presentation of synthetic visual objects (3 s) and predictive temporal context (30 s) in the order of appearance of such objects. Methods:Visual objects were complex and rotated in three dimensions about varying axes. Observers viewed fifteen (15) objects recurring many times each, intermixed with other objects that appeared only once, while whole-brain BOLD activity was recorded. Over three successive days, observers grew familiar with the recurring objects and reliably distinguished them from others. As reported elsewhere (Kakaei & Braun, 2024), representational similarity analysis (RSA) of multivariate BOLD activity revealed 124 'object-selective' brain parcels with selectivity for recurring objects, located mostly in the ventral occipitotemporal cortex and the parietal cortex. Main results:Here, we extend RSA to the representation of predictive temporal context, specifically "temporal communities" formed by objects that tended to follow each other. After controlling for temporal proximity, we observed 27 'community-sensitive' brain parcels, in which pairwise distances between multivariate responses reflected community structure, eitherpositively(smaller distances within than between communities) ornegatively(larger distances within). Among object-selective parcels, 11 parcels werepositivelycommunity-sensitive in the primary visual cortex (2 parcels), the ventral occipital, lingual, or fusiform cortex (8 parcels), and the inferior temporal cortex (1 parcel). Among non-object-selective parcels, 12 parcels werenegativelycommunity-sensitive in the superior, middle, and medial frontal cortex (6 parcels), the insula (2 parcels), the putamen (1 parcel), and in the superior temporal or parietal cortex (3 parcels). Conclusion:We conclude that cortical representations of object shape and of predictive temporal context are largely coextensive along the ventral occipitotemporal cortex.