Development of cortical auditory processing and its association with speech understanding from childhood to adulthood

The maturation of the auditory system is critical for the development of speech perception from childhood through early adulthood. However, the developmental trajectories and behavioral significance of cortical responses to speech sounds, particularly in relation to frequency specificity, remain poorly understood. Here, we presented low-frequency (/m/) and high-frequency (/s/) speech sounds to 70 typically developing individuals aged 5–24 years and recorded early cortical responses (P1 and N1) using electroencephalography. We also examined associations between these neural responses and speech understanding in quiet and in the presence of speech interferers. The developmental trajectories of P1 and N1 revealed distinct age- and stimulus-dependent patterns, including both linear and non-linear changes across development. These findings delineate frequency-specific maturational profiles within the cortical auditory system and identify potential neurophysiological markers of speech perception, providing a normative benchmark for assessing atypical auditory development.