Aberrant resting state functional connectivity associated with callous-unemotional traits from late childhood through late adolescence

Background. Callous-unemotional (CU) traits are a marker of deficient socioemotional processing linked to severe conduct problems. Although resting-state studies implicate altered large-scale network organization in CU traits, few have comprehensively examined connectivity both within and between the default mode (DMN), salience (SN), and frontoparietal (FPN) networks and none have done so across development in large samples. Methods. Using data from the Adolescent Brain Cognitive Development (ABCD) Study (N = 11,868, 48% female), we examined associations between CU traits and resting-state functional connectivity (rsFC) within and between the DMN, FPN, and SN with repeated timepoints (4) across youth spanning 9 to 18 years-old. Linear mixed effects models were used to assess main effects of CU traits along with moderators of age and sex, and sensitivity analyses included covariates for co-occurring psychopathology. Results. CU traits were associated with reduced within-DMN rsFC. No interactions between CU traits and sex were found, but an interaction between CU traits and age emerged, showing a negative association between CU traits and DMN-SN rsFC was evident in mid-to-late adolescence, with higher-CU youth showing an age-related decline in DMN-SN rsFC. Conclusions. These findings suggest youth with elevated CU traits exhibit atypical development of resting-state connectivity in networks crucial for empathy and salience processing. Specifically, youth with elevated CU traits showed persistent DMN hypoconnectivity and a later-emerging but accelerated age-related segregation of DMN-SN connectivity during adolescence. This pattern may reflect delayed yet ultimately exaggerated differentiation of socioaffective networks, highlighting adolescence as a developmental window for interventions targeting socioemotional functioning.