The project has been implemented in line with the objectives and timeline described in the Description of Action, with all core work packages reaching an advanced or completed stage.
Study 1 (WP1)
This study examined how caregivers’ acoustic properties in infant-directed (ID) speech and singing vary as a function of infants’ age across the first year of life. The work included dataset curation, extraction of spectro-temporal modulation (STM) features and related acoustic descriptors, and the application of statistical models to characterize developmental trajectories. Data preprocessing and primary analyses have been completed.
Study 2 (WP2 & WP3)
This study investigated how auditory and visual rhythmic cues of ID speech and singing shape the temporal dynamics of infant attention. The work involved the creation of audiovisual stimuli (including experimentally manipulated conditions isolating auditory and visual rhythms), development and validation of the experimental task, infant eye-tracking data collection, preprocessing of multimodal data (gaze, motion, and acoustic features), and implementation of time-resolved and model-based analyses (e.g. permutation-based approaches and temporal response function models). Data collection and primary analyses for a substantial portion of the sample have been completed.
Across both studies, the project also included dissemination activities, open science practices (e.g. preregistration, sharing of materials), and manuscript preparation.
Main achievements
- Sensitivity of spectro-temporal modulation (STM) to communicative context and development.
The project demonstrates that STM reliably captures differences between ID speech and singing, and is sensitive to subtle, continuous age-related changes in how caregivers structure these interactions across the first year of life.
- Complementary roles of auditory and visual rhythms in shaping infant attention.
The project shows that auditory and visual rhythmic cues make dissociable contributions to attentional dynamics: visual cues act as a robust driver of phase alignment, whereas auditory rhythms modulate the temporal structure of that alignment.
- Evidence for flexible, cross-modal temporal tuning.
When both modalities are present, infants adjust the tempo of their attentional alignment to match faster, hierarchically nested auditory rhythms, indicating sensitivity to cross-modal temporal structure.
- Integration of naturalistic and experimental approaches.
The project successfully combines ecologically valid stimuli with controlled manipulations of modality-specific information, enabling causal inference about the role of rhythmic cues.
- Methodological advancement in time-resolved analysis of attention.
The use of event-based analyses, permutation testing, and temporal response function modelling provides a robust framework for quantifying attention in dynamic social contexts.
- Commitment to open and reproducible science.
Preregistration, sharing of materials and data, and transparent analytical pipelines enhance reproducibility and reuse.
