White matter tracts underlying rhythm perception in adolescence

Adolescence is a critical developmental stage marked by significant neuropsychological changes coinciding with the maturation of white matter microstructure. Recent studies suggest that musical rhythm processing may serve both as a sensitive marker and a cognitive foundation for intervention strategies in adolescent neuropsychological development. However, our understanding of the white matter networks supporting rhythm processing in this age group remains limited. In this study, we investigated the extent to which the microstructure of white matter fiber tracts correlated with beat-based (detection of regular pulses) and sequence-based (discrimination of rhythmic patterns) rhythm perception in 65 typically developing adolescents. Our findings indicate that shared white matter networks, including the fornix, cerebellar tracts, and the body and tapetum of the corpus callosum, are critical for both beat-based and sequence-based rhythm perception. These pathways are involved in temporal sequence processing, duration-based timing, and interhemispheric communication. Additionally, specific sensorimotor pathways, including the bilateral superior longitudinal fasciculi I (SLF_I) and the middle cerebellar peduncle, were linked to beat-based perception, supporting the integration of auditory inputs with motor planning and execution. In contrast, the bilateral cingulum bundles, which are involved in memory processes, were specifically associated with sequence-based rhythm perception. Notably, the relationship between beat-based rhythm perception and both the left SLF_I and fornix became non-significant after adjusting for rapid automatized naming skill, suggesting shared neural resources between these processes. These findings suggest that the white matter pathways associated with rhythm perception in adolescents integrate sensorimotor and memory systems, with potential applications for rhythm-based interventions in developmental disorders.