Cognitive modeling informs interpretation of go/no-go task-related neural activations and their links to externalizing psychopathology

Background: Individuals with ADHD and other forms of externalizing psychopathology tend to display poor behavioral performance on the go/no-go task, which is thought to reflect deficits in inhibitory control. However, clinical neuroimaging studies using this paradigm have yielded conflicting results, raising basic questions about what the task measures and which aspects of the task relate to clinical outcomes of interest. We aimed to provide a clearer understanding of how neural activations from this paradigm relate to the cognitive mechanisms that underlie performance and the implications of these relationships for clinical research. Methods: 143 emerging adults (ages 18-21) performed the go/no-go task during fMRI scanning. We used the diffusion decision model (DDM), a mathematical modeling approach, to quantify distinct neurocognitive processes that underlie go/no-go performance. We then correlated DDM parameters with brain activation across several standard go/no-go contrasts and assessed relationships of DDM parameters and associated neural measures with clinical ratings. Results: Fronto-parietal activations on correct inhibition trials, which have typically been assumed to isolate neural processes involved in inhibition, were unrelated to either individuals response biases or their efficiency of task performance. In contrast, responses to false alarms in brain regions putatively responsible for error monitoring were strongly related to more efficient performance on the task and correlated with externalizing behavior and ADHD symptoms. Conclusions: Our findings cast doubt on conventional interpretations of go/no-go task-related activations as reflecting inhibition functioning. We instead find that error-related contrasts provide clinically-relevant information about neural systems involved in monitoring and optimizing cognitive performance.