Sign language communication enhances representations for hands in high-level visual cortex
High-level visual cortex supports the perception and recognition of visual categories. What is the role of experience in shaping this region and the time course over which it stays malleable? We tested whether experience with a sign language, where information is conveyed via the hands and face, shapes category representations in high-level visual cortex. We acquired functional MRI data from 20 hearing signers and 20 non-signers while they viewed images from ten categories, including faces and hands. We compared the neural distinctiveness and size of category-selective regions between groups in ventral temporal and lateral occipito-temporal cortex. Signers showed higher distinctiveness for hands and larger hand-selective regions than non-signers in the left hemisphere, and sign language experience predicted neural hand representations. Critically, ventral hand representations were also enhanced in signers who learned sign language in adulthood. These findings indicate that visual cortex retains experience-dependent plasticity into adulthood, with implications for visual learning and cortical development.