DOI: 10.5061/dryad.q573n5tj2
title: Data from: The MRi-Share database: Brain imaging in a cross-sectional cohort of 1,870 university students

description: We report on MRi-Share, a multi-modal brain MRI database acquired in a
 unique sample of 1,870 young healthy adults, aged 18 to 35 years, while
 undergoing university-level education. MRi-Share contains structural (T1
 and FLAIR), diffusion (multispectral), susceptibility weighted (SWI), and
 resting-state functional imaging modalities. Here, we described the
 contents of these different neuroimaging datasets and the processing
 pipelines used to derive brain phenotypes, as well as how quality control
 was assessed. In addition, we present preliminary results on associations
 of some of these brain image-derived phenotypes at the whole brain level
 with both age and sex, in the subsample of 1,722 individuals aged less
 than 26 years. We demonstrate that the post-adolescence period is
 characterized by changes in both structural and microstructural brain
 phenotypes. Grey matter cortical thickness, surface area and volume were
 found to decrease with age, while white matter volume shows increase.
 Diffusivity, either radial or axial, was found to robustly decrease with
 age whereas fractional anisotropy only slightly increased. As for the
 neurite orientation dispersion and densities, both were found to increase
 with age. The isotropic volume fraction also showed a slight increase with
 age. These preliminary findings emphasize the complexity of changes in
 brain structure and function occurring in this critical period at the
 interface of late maturation and early aging.
description: The dataset is based on magnetic resonance imaging (MRI) data
 collected as part of MRiShare database. The anatomical and
 diffusion-weighted imaging data from 1,832 healthy subjects were processed
 as described in the associated publication. The dataset contains global
 imaging-derived phenotypes (IDPs) described in the paper.
description: The dataset can be used with the associated R script
 <em>Global_morphometry</em> List of
 variables and their units: Age:  age in
 years Sex: F-females, M-males
 eTIV: estimate of total intracranial volume based on Freesurfer
 v6.0 in mm<sup>3</sup> FS6_mean_CT: mean
 CT based on Freesurfer v6.0 in mm FS6_total_innerCSA:
 total inner(white) CSA based on Freesurfer v6.0 in
 mm<sup>2</sup> FS6_total_pialCSA: total
 pial CSA based on Freesurfer v6.0 in mm<sup>2</sup>
 SPM_GM_volume: total grey matter volume based on
 SPM12 in mm<sup>3</sup> SPM_WM_volume:
 total white matter volume based on SPM12 in mm<sup>3</sup>
 FS6_cerebralWM_mask_vol: volume of the cerebral
 white matter mask based on Freesurfer v6.0 segmentation in
 mm<sup>3</sup> cerebralWM_mean_FA: mean
 FA within the subject-specific cerebral WM mask (unitless)
 cerebralWM_mean_MD: mean MD within the subject-specific cerebral
 WM mask in mm<sup>2</sup>/sec
 cerebralWM_mean_AD: mean AD within the subject-specific cerebral
 WM mask in mm<sup>2</sup>/sec
 cerebralWM_mean_RD: mean RD within the subject-specific cerebral
 WM mask in mm<sup>2</sup>/sec
 cerebralWM_mean_NDI: mean NDI within the subject-specific
 cerebral WM mask (unitless) cerebralWM_mean_ISOVF:
 mean ISOVF within the subject-specific cerebral WM mask
 (unitless) cerebralWM_mean_ODI: mean ODI within the
 subject-specific cerebral WM mask (unitless) 
 Missing data:  Due to the premature end of the
 scanning session, data from 9 subjects are missing for the IDPs based on
 DWI (last 8 columns). These are coded as NA. Also, one
 participant withdrew from the study since the writing of the associated
 publication, and therefore data contain values from 1,831, instead of
 1,832 participants.