Cortical contributions to the auditory frequency-following response revealed by MEG

TLDR

The auditory frequency‑following response (FFR) to complex periodic sounds is used to study subcortical hearing and as a biomarker for disorders, yet its neural origins remain unclear. Using magnetoencephalography, we observed a strong, right‑asymmetric cortical contribution to the FFR at the stimulus fundamental frequency, alongside signals from the cochlear nucleus, inferior colliculus, and medial geniculate. The cortical component of the FFR informs plasticity, pathology, and higher‑level cognition, suggesting that previous FFR interpretations may need re‑examination with source‑separation methods.

Abstract

Abstract The auditory frequency-following response (FFR) to complex periodic sounds is used to study the subcortical auditory system, and has been proposed as a biomarker for disorders that feature abnormal sound processing. Despite its value in fundamental and clinical research, the neural origins of the FFR are unclear. Using magnetoencephalography, we observe a strong, right-asymmetric contribution to the FFR from the human auditory cortex at the fundamental frequency of the stimulus, in addition to signal from cochlear nucleus, inferior colliculus and medial geniculate. This finding is highly relevant for our understanding of plasticity and pathology in the auditory system, as well as higher-level cognition such as speech and music processing. It suggests that previous interpretations of the FFR may need re-examination using methods that allow for source separation.