Linking Vestibular, Tactile, and Somatosensory Rhythm Perception to Language Development in Infancy

First experiences with rhythm occur in the womb, with different rhythmic sources being available to the human fetus. Among sensory modalities, vestibular, tactile, and somatosensory perception (VTS; Provasi et al., 2014) plays a crucial role in early processing (Phillips-Silver and Trainor, 2005; Tichko et al., 2021). However, a restricted corpus of studies specifically focused on VTS rhythms in language development. Therefore, the present work investigated VTS rhythmic abilities and their role in language acquisition through two experiments with 45 infants (21 females, sex assigned at birth; M age = 661.6 days, SD = 192.6) with middle/high socioeconomic status. Specifically, VTS rhythmic abilities were firstly assessed through a vibrotactile tool for music perception (Experiment 1). In Experiment 2, linguistic abilities were evaluated in the same cohort, specifically testing phonological and prosodic processing. Discrimination abilities for rhythmic and linguistic stimuli were inferred from changes in pupil diameter to contingent visual stimuli over time, through a Tobii X-60 eye-tracker (Hepach and Westermann, 2016; Mathôt, 2018; Calignano et al., 2021; Russo et al., 2021). The predictive effect of VTS rhythmic abilities on linguistic processing and the developmental changes occurring across ages were explored by means of generalized, additive and linear, mixed-effect models (Baayen et al., 2008; 2017; van Rij et al., 2019). Results are discussed in terms of cross-sensory (i.e., haptic to hearing) and cross-domain (i.e., music to language) effects of rhythm on language acquisition, with implications for typical and atypical development.