DOT has an undisputed potential for investigating whole-brain hemodynamics in the neonatal population.6,13,25–31 Prior studies in this field have raised the issue related to the cap tolerance by the neonates as a possible factor limiting the duration of DOT data acquisition. Singh et al.6 and Chalia et al.13 adopted a soft and flexible cap (EasyCap, Germany, i.e., our outer layer), with a whole-head coverage for a multimodal DOT-EEG acquisition. Ferradal and colleagues14 employed a custom-made optode holder, composed of five triangular patches joined together with a neoprene headband, fixed to the head via Velcro straps. A layer of flexible plastic was the structural support of the cap and a layer of soft silicone was used to embed the optical fibers. The optode array covered the occipital, temporal, and inferior parietal cortices. Austin et al.32 employed a custom-made helmet with whole-head coverage, made of an outer shell of thermoplastic and an inner part of NIR-absorbing foam. Crucially, in all these DOT studies, the length of registration did not exceeded 2 h, with a minimal length of 60 min6,14 up to a maximum of 115 min13 and the gestational age ranged from 34 weeks gestation13 to term.