This retrospective analysis was approved by the Institutional Review Board at BCH. The clinical imaging database at BCH was retrospectively reviewed for this analysis from 01 January 2008 until 24 February 2016. All MRI examinations that included brain imaging of participants aged 0–32 years at the time of imaging were included for further analysis. Examinations deemed to be of low quality (because of excessive participant motion, large metal artefact from a subject’s dental hardware, lack of a T1 structural imaging volume providing diagnostically useful axial, sagittal, and coronal oriented images, etc.) were excluded from the study. Examinations and medical records that were inaccessible because of technical reasons were excluded. Healthy subjects were retrospectively identified from routine clinical imaging by including subjects with a normal MRI examination as assessed by a BCH radiologist and whose medical records provide no indication of any substantive neurological problems (subjects with any known neurodevelopmental disorder were excluded such as autism, cerebral palsy, attention deficit hyperactivity disorder, epilepsy, neurofibromatosis, developmental delay, tuberous sclerosis complex, hemiplegia, hallucinations, any brain tumor, bipolar disorder, obsessive compulsive disorder, abnormal psychological factors, meningitis, encephalopathy, postconcussion syndrome, learning disabilities, abnormal EEG examination, paresthesia, Bardet–Biedl syndrome, Waardenburg syndrome, cerebral venous thrombosis, demyelination, etc.). Participants with any type of cancer (including outside the central nervous system) were excluded to avoid neurological data with altered growth trajectories caused by common treatments such as chemotherapy. This yielded 993 examinations (395 male, 598 female) from 988 participants. A joint histogram demonstrating the age distributions for both the male and female healthy participants are provided in Figure 1.