These novel preliminary results suggest that ECN functional connectivity may differ between OUD and HC. This finding is consistent with previous research showing altered executive function in OUD and supports further examination of ECN functional connectivity in association with treatment response in OUD. Given our relatively small sample size (50 subjects total; 25 subjects per group), the statistically significant difference in demographic variables between groups, and the heterogeneity within our OUD group, our results should be treated as preliminary for hypothesis generation. Replication of these results will be needed in future studies.