Abstract:
The Adolescent Brain Cognitive Development (ABCD) Study is a longitudinal neuroimaging study of unprecedented scale that is in the process of following over 11,000 youth from middle childhood though age 20. The study's primary measure of inhibitory control, the stop-signal task, has a unique design feature that violates "context independence", an assumption critical to the measurement model used to index inhibitory ability on the task, leading some experts to recently call for the task to be changed and caution against the use of previously-collected data. We developed a formal cognitive process model to explain the effects of this design feature on behavior, and therefore allow the impact of the violation on estimates of inhibitory ability to be quantified and accounted for. Discussion topics will include advantages of using formal process models in cognitive neuroscience research, the trade-off between model complexity and parameter estimation, and necessary conditions for using cognitive models to measure individual differences in psychological processes.