Fig. 1: A schematic overview of data analysis steps.

With the fMRI data (while performing the SST task) collected at age 19 in the IMAGEN study, we parcellated the brain using the 268-node Shen atlas and computed Pearson’s correlation for all pairwise combinations of the mean time course of the nodes to estimate brain-wide functional connectivity. We then used the functional connectivity data to run ten-fold, cross-validated CPM analyses to identify neural networks that predict impulsivity and neuroticism measures and obtain brain-behavior association models. We externally validated the CPM models using data from the ABCD study. We conducted three main analyses: 1) anatomical summarization of the neural signatures of impulsivity and neuroticism based on their overlap with canonical neural networks, 2) comparison of impulsivity and neuroticism signatures to identify their unique vs. shared anatomical features, and 3) comparison of the impulsivity and neuroticism signatures with a recently identified neural network implicated in alcohol-use risk.