The ABCD Stop Signal Data: Response to Bissett et al.

Abstract

This paper responds to a recent critique by Bissett and colleagues ( https://www.biorxiv.org/content/10.1101/2020.05.08.084707v1) of the fMRI Stop task being used in the Adolescent Brain Cognitive Development (ABCD) study. The critique focuses primarily on a design feature of the task that the authors contend might lead to a violation of race model assumptions (i.e., that the Go and Stop processes are fully independent) which are relevant to the calculation of the Stop Signal Reaction Time, a measure of the inhibition process. Bissett and colleagues also raise a number of secondary concerns. In this response we note that satisfying race model assumptions is a pernicious challenge for Stop task designs but also that the race model is quite robust against violations of its assumptions. Most importantly, while Bissett et al. raise conceptual concerns with the task we focus here on analyses of both the performance and the neuroimaging data and we conclude that the concerns appear to have minimal impact on the task data. We note that there were errors in the analyses conducted by Bissett et al. that inflated their estimates of race model violations in ABCD, that they did not apply any performance-based exclusions to the data they analyzed, that a number of the errors that they flagged were already identified and corrected in the ABCD annual data releases, and we argue that a number of the other concerns reflect sensible design decisions. In this paper, we list some adjustments that will be made to the task and some new flags that will be added to the annual, curated data releases. We stress that the ABCD data are fully available to the scientific community who are empowered to apply whatever inclusion and exclusion criteria they deem appropriate for their analyses and we conclude that the ABCD Stop task yields valuable data that researchers can use to track adolescent neurodevelopment.