Dissociable changes in temporal precision and causal expectations following perceptual training

Abstract

A common behavioral gain does not necessarily reflect a common learning mechanism. Perceptual learning may sharpen sensory evidence without updating higher-level expectations about its causes. Across three experiments, we examined audiovisual binding and its plasticity in children with ADHD and typically developing children. Children with ADHD were more susceptible to the sound-induced flash illusion (Experiment 1) and showed markedly flatter temporal tuning of it (Experiment 2), yet conventional temporal binding window (TBW) estimates did not distinguish the groups, behavior alone could not localize the difference. Following six days of simultaneity-judgment training, both groups became comparably less susceptible to the illusion. A temporally explicit two-dimensional Bayesian causal inference model, however, revealed sharply different latent changes. Typically developing children reduced their causal prior expectation that auditory and visual signals shared a common cause. Children with ADHD showed no corresponding prior recalibration but instead exhibited a marked reduction in temporal uncertainty, indicating more precise perceptual evidence that did not propagate to the slower, more abstract estimate of environmental causal structure. Thus, perceptual learning converged at the behavioral level while diverging computationally. These findings argue against unitary accounts of multisensory plasticity and show how the same perceptual endpoint can conceal adaptation at different levels of the inferential hierarchy.