Fixel-based analysis
After the pre-processing, dMRI images were analyzed using the recommended multi-tissue FBA analysis pipeline from Mrtrix3 (version 3.0rc3).Each subject data was up-sampled to 1.3 mmFBA was performed to study the longitudinal micro- and macrostructural changes occurring during very preterm infants’ brain development, from the 33rd week GA to term-equivalent age, and to evaluate the impact of the music intervention on the significant brain structural changes occurring during this period.For this purpose, an unbiased study-specific FOD template was computed using 40 intra-subject templates (19 PTC and 21 PTM). In order to generate the intra-subject templates, the time-point 1 and time-point 2 subjects’ FOD maps were first rigidly transformed to midway space and then averaged. These intra-subject templates served as input to create the final study-specific population template used for the longitudinal analyses (Whole-brain tractography was performed in template space, using Mrtrix3 iFOD2 algorithm (