The YOUth cohort study: MRI protocol and test-retest reliability in adults

Abstract

The YOUth cohort study is a unique longitudinal study on brain development in the general population. As part of the YOUth study, 2000 children will be included at 8, 9 or 10 years of age and planned to return every three years during adolescence. Magnetic resonance imaging (MRI) brain scans are collected, including structural T1-weighted imaging, diffusion-weighted imaging (DWI), resting-state functional MRI and task-based functional MRI. Here, we provide a comprehensive report of the MR acquisition in YOUth Child & Adolescent including the test-retest reliability of brain measures derived from each type of scan. To measure test-retest reliability, 17 adults were scanned twice with a week between sessions using the full YOUth MRI protocol. Intraclass correlation coefficients were calculated to quantify reliability. Global brain measures derived from structural T1-weighted and DWI scans were reliable. Resting-state functional connectivity was moderately reliable, as well as functional brain measures for both the inhibition task (stop versus go) and the emotion task (face versus house). Our results complement previous studies by presenting reliability results of regional brain measures collected with different MRI modalities. YOUth facilitates data sharing and aims for reliable and high-quality data. Here we show that using the state-of-the art YOUth MRI protocol brain measures can be estimated reliably.

Keywords: Adolescence; Intraclass correlation coefficient; Longitudinal brain development; Magnetic resonance imaging; Test-retest reliability; Youth (Youth of Utrecht) cohort study.

Fig. 1

Scan types collected in YOUth in order of acquisition. 1) Original T1-weighted scan (left), with subcortical and cortical brain tissue segmentation (middle) and the cortical regions of interest (right). 2) Diffusion unweighted volume after preprocessing (left); the intersection of the white matter regions (colored) and the skeleton plotted on the FA map (middle); the reconstructed fiber tracts used to create the connectivity maps (right). 3) One dynamic volume of the fMRI scan (left) and a schematic representation of how functional connectivity is computed (right). 4) One dynamic volume of the fMRI scan (left) and task-related activity during the face-processing in the emotion task (right).

Fig. 2

Monitoring scanner performance with human and phantom data using dynamic EPI scans. Data on scanner stability over the course of the study. The solid horizontal line indicates the mean of the signal and the dotted line indicates a threshold of ±3 standard deviations from the mean.

Fig. 3

Test-retest ICCs of subcortical and cortical brain measures. The first row shows the ICCs of subcortical volumes on two coronal slices. The slice on the left cuts through the caudate nucleus, thalamus, putamen, pallidum, amygdala and hippocampus. The slice on the right cuts more anterior through the caudate nucleus, putamen and nucleus accumbens. The second, third and fourth row show ICCs of cortical volume, cortical surface area and cortical thickness respectively. The last row shows vertex-wise cortical thickness ICCs. The ICCs of cortical measures are shown on the surface from an outer and medial view with the left hemisphere on the left and the right hemisphere on the right. To visualize the regional test-retest reliability, a model brain was created using the first scan of each participant (Peper et al., 2009; supporting information) and segmented and parcellated with FreeSurfer. For each region or vertex, the ICC was recoded to an RGB color-code using colormap jet in MATLAB.

Fig. 4

Histogram of the test-retest ICC's of the 1053 included edges. The bin size of the histogram is 0.05.

Fig. 5

Test-retest ICCs for each individual edge. The upper-left triangle shows the results for the connections weighted with mean FA while the lower-right triangle shows the results for the connections weighted with the number of streamlines. Edges that are colored black were excluded for containing too few streamlines in too many subjects.

Fig. 6

Group-mean functional connectivity (A) and test-retest reliability (B) of functional connectivity for connections between regions of cortical resting-state networks. Abbreviations: DMN = default mode network; SMN = sensorimotor network; VN = visual network; SN = salience network; DAN = dorsal attention network; FPN = frontoparietal network; LN = language network; CBN = cerebellar network; TP1 = estimates from test session; TP2 = estimates from retest session.