Abstract
Recurring structures forming regular patterns are common in sounds. Learning such patterns is thought to be crucial for accurate auditory perceptual organization (scene analysis) and efficient recognition and prediction of sounds. The current study investigated the behavioral and neural signatures of rapid perceptual learning of regular patterns in sounds. In six behavioral and EEG experiments with over 120 human participants from both sexes, we show that individuals are faster to detect regular patterns, are more sensitive to pattern deviations, and are more accurate at judging the temporal order of pattern onset relative to a visual stimulus when patterns are repeated compared to novel. Sustained neural activity indexed perceptual learning in two ways. First, sustained activity increased earlier for repeated compared to novel regular patterns when participants attended to sounds, but not when they ignored them; this earlier response increase mirrored the rapid perceptual learning we observed behaviorally. Second, the magnitude of sustained activity was reduced for repeated compared to novel patterns, independent of whether participants attended to or ignored sounds. The reduction in the magnitude of sustained activity appeared only for later stimulus presentations, suggesting it is not directly related to perceptual learning, but to processes enabled by learning. Our study thus reveals neural markers of perceptual learning of auditory patterns, and of processes that may be related to reduced novelty or better prediction of learned auditory patterns.
Significance statement Perceptual learning of regular patterns in sounds may optimize perception, but not much is known about the underlying neural processes. We observed several behavioral indices of perceptual learning, including faster pattern detection and increased sensitivity to pattern deviations for repeated compared to novel patterns. Sustained neural activity – indexing pattern processing – increased earlier for repeated than novel patterns, mirroring perceptual learning observed behaviorally. The magnitude of sustained activity was reduced for repeated relative to novel patterns. This reduction appeared only for later stimulus presentations, suggesting it is not directly related to perceptual learning. Our study thus neurally characterizes the perceptual learning of auditory patterns and of subsequent processes that may index reduced novelty or increased prediction of learned auditory patterns.
Competing Interest Statement
The authors have declared no competing interest.