Neural coding of auditory rhythm develops in the course of the third trimester of human gestation
School/Affiliation:Institut National de la Santé et de la Recherche Médicale (INSERM) U1105, GRAMFC, Université de Picardie Jules Verne, Amiens, France, 80054 Amiens, France
Co-Authors:Mohammadreza Edalati, Ghida Ghostine, Guy Kongolo, Fabrice Wallois, Laurel J Trainor, Sahar Moghimi
Virtual or In-person:Virtual
The ability to perceive and synchronize with auditory rhythms is important for the development of language and musical skills. While previous studies show neural responses to the rhythmic structures and selective enhancement of both beat and meter (i.e., beat groups), the evolution of the neural response to rhythm remains understudied during early development.
We used high-resolution electroencephalography while sleeping premature newborns (n = 46, age range: 28–36 wGA) were exposed to an ambiguous duple/triple auditory rhythm in the incubator. We evaluated the impact of gestational age on the neural response to the rhythmic hierarchy by comparing the steady-state evoked potentials (SSEPs) and brain-stimulus synchronization at the beat- and meter-related frequencies between two groups of premature newborns; those born before 33 wGA and those born after 33 wGA.
We observed that both age groups synchronized to the relatively fast periodicity related to the beat frequency, whereas synchronization to the meter-related (grouping) frequencies was present only in the older group. Furthermore, our analysis of the circular variability of the synchronization phase for the beat frequency (i.e., how well the neural response aligned with stimulus onsets) revealed that with increasing gestational age, the neural phase decreased in variability, and became closer to that of the stimulus, showing better alignment with the periodicity related to the beat.
Our findings suggest that newborn’s neural capacities for encoding metrical (grouping) structures develop considerably between 28 and 36 wGA. This gradual development provides the possibility for perception abilities to be shaped by prenatal auditory rhythmic experiences.