Contributions of the subcortical auditory system to predictive coding and the neural encoding of speech

Prevalent views in cognitive neuroscience have highlighted the auditory cortex (AC) as the major neuroanatomical site for auditory cognition. Yet, this view suffers from 'cortical myopia' as it neglects the intricate functional architecture of the subcortical auditory pathway. Here, I will review evidence indicating that key anatomical structures in the auditory hierarchy, such as the inferior colliculus and the medial geniculate body, play major roles in statistical learning and predictive processing, thus contributing to auditory perception. Furthermore, mounting evidence supports these subcortical structures as involved in the neural encoding of speech sounds, including categorical perception, and in early language acquisition when the AC is still immature. I will argue that a brain potential known as frequency-following response provides a methodological tool to map high-level cognitive operations to the human subcortical auditory system. Future studies should emphasize the precise interplay between cortical and subcortical structures in supporting auditory cognition.