Long-term priors constrain category learning in the context of short-term statistical regularities

Cognitive systems face a constant tension of maintaining existing representations that have been fine-tuned to long-term input regularities and adapting representations to meet the needs of short-term input that may deviate from long-term norms. Systems must balance the stability of long-term representations with plasticity to accommodate novel contexts. We investigated the interaction between perceptual biases or priors acquired across the long-term and sensitivity to statistical regularities introduced in the short-term. Participants were first passively exposed to short-term acoustic regularities and then learned categories in a supervised training task that either conflicted or aligned with long-term perceptual priors. We found that the long-term priors had robust and pervasive impact on categorization behavior. In contrast, behavior was not influenced by the nature of the short-term passive exposure. These results demonstrate that perceptual priors place strong constraints on the course of learning and that short-term passive exposure to acoustic regularities has limited impact on directing subsequent category learning.

Intact Susceptibility to Visual Illusions in Autistic Individuals

Altered sensory perception, a core characteristic of autism, has been attributed to attenuated use of stimuli context or prior information in perception. Reduced susceptibility to perceptual illusions was extensively used to support these accounts for autistic perception. However, empirical evidence has been inconsistent. The current study systematically investigated susceptibility to size illusions in autistic and non-autistic individuals using a standardized psychophysical battery. Eighty-one participants, 41 autistic and 40 non-autistic individuals, completed the Ben-Gurion University Test for Perceptual Illusions (BTPI), measuring susceptibility to the Ponzo, Ebbinghaus, and Height-width illusions. The results demonstrate clear evidence for susceptibility to illusions in the perception of size both in the autistic and non-autistic groups. No significant differences were found between groups in the magnitude of illusion on the perceived size, or on the perceptual resolutions of size (discrimination thresholds) in any of the illusory settings tested. The results challenge current theories suggesting reduced reliance on priors or enhanced sensory measurement in autism. Instead, using robust psychophysical methods, the study provides clear evidence for autistic people forming priors and using long-term knowledge in perception.