Signal but not noise changes with perceptual learning

Perceptual discrimination improves with practice. This ‘perceptual learning’ is often specific to the stimuli presented during training1,2,3,4,5, indicating that practice may alter the response characteristics of cortical sensory neurons6,7. Although much is known about how learning modifies cortical circuits8, it remains unclear how these changes relate to behaviour. Different theories assume that practice improves discrimination by enhancing …