Cortical surfaces from 270 infants were extracted and first projected onto the sphere. Templates were then generated in two stages: first, a reference space was initialised via affine alignment to a group average adult template. Following this, templates were iteratively refined through repeated alignment of individuals to the template space until the variability of the average feature sets converged. Finally, bias towards the adult reference was removed by applying the inverse of the average affine transformations on the template and de-drifting the template. We used temporal adaptive kernel regression to produce age-dependant atlases for 9 weeks (36 to 44 weeks PMA).
The atlas construction is described in detail in:
Jelena Bozek; Antonios Makropoulos; Andreas Schuh; Sean Fitzgibbon; Robert Wright; Matthew F Glasser; Timothy S Coalson; Jonathan O’Muircheartaigh; Jana Hutter; Anthony N Price; Lucilio Cordero-Grande; Rui Pedro A Teixeira; Emer Hughes; Nora Tusor; Kelly Pegoretti Baruteau; Mary A Rutherford; A David Edwards; Joseph V Hajnal; Stephen M Smith; Daniel Rueckert; Mark Jenkinson; Emma C Robinson; Construction of a Neonatal Cortical Surface Atlas Using Multimodal Surface Matching in the Developing Human Connectome Project, NeuroImage, vol. 179, pp. 11-29, 2018.
Link to paper: https://doi.org/10.1016/j.neuroimage.2018.06.018
You can download the atlas from here.