Visual statistical learning and integration of perceptual priors are intact in attention deficit hyperactivity disorder

Abstract

Abstract Deficits in statistical learning and predictive processing could in principle explain inattention and distractibility in attention deficit hyperactivity disorder (ADHD). To test this, we evaluated whether adults diagnosed with ADHD ( n = 17) differed from controls ( n = 30) in implicitly learning and using low-level perceptual priors to guide sensory processing. We used a visual statistical learning task in which participants had to estimate the direction of coherently moving dots. Unbeknown to the participants, two directions were more frequently presented than the others, creating an implicit bias (prior) towards those directions. This task had previously revealed differences in autistic spectrum disorder and schizophrenia. Both groups acquired the prior expectations for the most frequent directions and, except for some subtle differences over time, there were no group difference in how much the priors influenced performance. This suggests that ADHD symptoms do not stem from difficulties in developing and/or using perceptual priors. Statement of Relevance Schizophrenia, autistic spectrum disorder (ASD), and more recently anxiety and depression have all been described in terms of disturbances in predictive coding or Bayesian inference – a general mechanism for how incoming sensory information is integrated with prior knowledge and how such prior knowledge is learnt. In theory, Attention deficit hyperactivity disorder (ADHD) is also associated with a range of sensory processing differences that could be understood within the Bayesian inference framework. However, to our knowledge, there has been no experimental work explicitly testing differences in Bayesian inference in ADHD so far. Here we found the acquisition and use of the low-level perceptual priors to be intact in ADHD, compared to controls. Our study shows for the first time that the learning and use of low-level Bayesian priors are not impaired in ADHD, contrary to what has been described in other neurodevelopmental disorders.