Early face deprivation leads to long-lasting deficits in cortical face processing

Experience-dependent plasticity in early sensory cortex is restricted to critical periods that occur early in development. In contrast, when during development higher-order cortical areas show experience-dependent plasticity remains unclear. In the primate ventral visual stream, face-selective cortex emerges with experience during development, providing a powerful system for testing how the timing of experience shapes higher-order representations. Here, we leveraged a unique macaque model of selective face deprivation followed by years of normal face exposure to causally test late plasticity in higher-order visual cortex. We found that face-deprived monkeys acquire face-directed viewing behavior and neural face selectivity after post-deprivation exposure. However, their neural representations retained lasting signatures of early experience, including mixed face and hand selectivity and impaired tuning for face identity, expression, and viewpoint. These findings demonstrate that higher-order visual cortex remains plastic beyond early development, but that the timing of experience fundamentally constrains the refinement of later-acquired neural representations.