Abstract
Over the past decade, there have been significant advances in understanding how primates recognize objects in the presence of identity-preserving variations. However, primates' vision encompasses more than object recognition. In the dynamic world, an effective interaction with moving objects and the ability to infer and predict their motion are essential for survival. In this study, we systematically investigated hierarchically connected brain areas in the ventral visual pathway of rhesus macaques (areas V4 and IT), implicated in object recognition, to first characterize their responses to object motion, speed, and direction. Subsequently, we quantified the correlative links between these responses and two distinct object motion-based behaviors, one reliant on information directly available in videos (e.g., velocity discrimination) and the other predicated on predictive motion estimates from videos (e.g., future frame predictions). Further, by employing causal microsimulation strategies, we tested the critical role of the macaque IT cortex in these behaviors. Interestingly, while current computational models of object and action recognition are accurate on stationary object-based tasks, we observed that their predictions suffer significant deficits in our dynamic tasks compared to primates. These findings call into question the widely accepted demarcation of the primate ventral and dorsal cortices into the "what" and "where" pathways. These explorations highlight the imperative to examine the interplay between these cortical hierarchies for a more profound understanding of visual motion perception, which serves as a gateway to intuitive physics. The data also provide valuable empirical constraints to guide the next generation of dynamic brain models.