Three principles for the utility of simple tasks that assess elemental processes in parsing heterogeneity.

As clinical psychological science and biological psychiatry push to assess, model, and integrate heterogeneity and individual differences, approaches leveraging computational modeling, translational methods, and dimensional approaches to psychopathology are increasingly useful in establishing brain-behavior relationships. The field is ultimately interested in complex human behavior, and disruptions in such behaviors can arise through many different pathways, leading to heterogeneity in etiology for seemingly similar presentations. Parsing this complexity may be enhanced using "simple" tasks-which we define as those assaying elemental processes that are the building blocks to complexity. Using eyeblink conditioning as one illustrative example, we propose that simple tasks assessing elemental processes can be leveraged by and enhance computational psychiatry and dimensional approaches in service of understanding heterogeneity in psychiatry, especially when these tasks meet three principles: (a) an extensively mapped circuit, (b) clear brain-behavior relationships, and (c) relevance to understanding etiological processes and/or treatment. (PsycInfo Database Record (c) 2024 APA, all rights reserved).