Effective connectivity analysis of response inhibition functional architecture

Monica Di Giuliano ¹ Andy Schumann ^1* Feliberto De La Cruz ¹ Pedro Henrique Rodrigues Da Silva ² Karl-Jürgen Bär ¹

• ¹ University Hospital Jena, Jena, Germany
• ² Faculty of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil

Inhibition mechanisms are essential in daily life, helping individuals adapt to environmental demands. However, the causal interactions between large-scale functional network involved in response inhibition remain poorly understood. In this study, we examined the effective connectivity underlying inhibitory processes in the brain using Dynamic Causal Modeling and Independent Component Analysis. We conducted a Go-NoGo fMRI task with 19 healthy participants to investigate these networks. Our results identified four functional networks activated during correct motor response inhibition: the salience network (SN), the right and left executive control networks (ECNs), and the ventral default mode network (vDMN). We found a significant causal inhibitory influence from the vDMN to the left ECN. In case of incorrect response inhibition condition, the SN, the bilateral ECN and the Somatomotor Network (SMN) were found to be prominently activated. Here, we outlined a significant correlation between the inhibitory influence from the SMN to the SN and the commission error rate. Ultimately, the correlation between self-reported impulsivity levels and the causal network interactions revealed that highly impulsive individuals require greater interhemispheric integration between right and left areas of the ECN for effective inhibition, as well as a causal excitatory modulation from the rECN to the vDMN. Bottom line, our study reveals complex hierarchical dynamics among functional networks during response inhibition. These findings offer valuable insight into the neural mechanisms supporting inhibition and open avenues for future research on the neural underpinnings of this critical cognitive function during the course of life-span.