Are Callous-Unemotional Traits Associated with Conflict Adaptation in Childhood?

Executive function and underlying brain network distinctions for callous-unemotional traits and conduct problems in adolescents

The complexity of executive function (EF) impairments in youth antisocial phenotypes of callous-unemotional (CU) traits and conduct problems (CP) challenge identifying phenotypic specific EF deficits. We can redress these challenges by (1) accounting for EF measurement error and (2) testing distinct functional brain properties accounting for differences in EF. Thus, we employed a latent modeling approach for EFs (inhibition, shifting, fluency, common EF) and extracted connection density from matching contemporary EF brain models with a sample of 112 adolescents (ages 13-17, 42% female). Path analysis indicated CU traits associated with lower inhibition. Inhibition network density positively associated with inhibition, but this association was strengthened by CU and attenuated by CP. Common EF associated with three-way interactions between density*CP by CU for the inhibition and shifting networks. This suggests those higher in CU require their brain to work harder for lower inhibition, whereas those higher in CP have difficulty engaging inhibitory brain responses. Additionally, those with CP interacting with CU show distinct brain patterns for a more general EF capacity. Importantly, modeling cross-network connection density in contemporary EF models to test EF involvement in core impairments in CU and CP may accelerate our understanding of EF in these phenotypes.

Efficiency of Heterogenous Functional Connectomes Explains Variance in Callous-Unemotional Traits After Computational Lesioning of Cortical Midline and Salience Regions

Introduction: Callous-unemotional (CU) traits are a youth antisocial phenotype hypothesized to be a result of differences in the integration of multiple brain systems. However, mechanistic insights into these brain systems are a continued challenge. Where prior work describes activation and connectivity, new mechanistic insights into the brain's functional connectome can be derived by removing nodes and quantifying changes in network properties (hereafter referred to as computational lesioning) to characterize connectome resilience and vulnerability. Methods: Here, we study the resilience of connectome integration in CU traits by estimating changes in efficiency after computationally lesioning individual-level connectomes. From resting-state data of 86 participants (48% female, age 14.52 ± 1.31) drawn from the Nathan Kline institute's Rockland study, individual-level connectomes were estimated using graphical lasso. Computational lesioning was conducted both sequentially and by targeting global and local hubs. Elastic net regression was applied to determine how these changes explained variance in CU traits. Follow-up analyses characterized modeled node hubs, examined moderation, determined impact of targeting, and decoded the brain mask by comparing regions to meta-analytic maps. Results: Elastic net regression revealed that computational lesioning of 23 nodes, network modularity, and Tanner stage explained variance in CU traits. Hub assignment of selected hubs differed at higher CU traits. No evidence for moderation between simulated lesioning and CU traits was found. Targeting global hubs increased efficiency and targeting local hubs had no effect at higher CU traits. Identified brain mask meta-analytically associated with more emotion and cognitive terms. Although reliable patterns were found across participants, adolescent brains were heterogeneous even for those with a similar CU traits score. Conclusion: Adolescent brain response to simulated lesioning revealed a pattern of connectome resiliency and vulnerability that explains variance in CU traits, which can aid prediction of youth at greater risk for higher CU traits.

Resting-state connectivity underlying cognitive control's association with perspective taking in callous-unemotional traits

Callous-Unemotional (CU) traits are often associated with impairments in perspective taking and cognitive control (regulating goal directed behavior); and adolescents with CU traits demonstrate aberrant brain activation/connectivity in areas underlying these processes. Together cognitive control and perspective taking are thought to link mechanistically to explain CU traits. Because increased cognitive control demands modulate perspective taking ability among both typically developing samples and individuals with elevated CU traits, understanding the neurophysiological substrates of these constructs could inform efforts to alleviate societal costs of antisocial behavior. The present study uses GIMME to examine the heterogenous functional brain properties (i.e., connection density, node centrality) underlying cognitive control's influence on perspective taking among adolescents on a CU trait continuum. Results reveal that cognitive control had a negative indirect association with CU traits via perspective taking; and brain connectivity indirectly associated with lower CU traits - specifically the social network via perspective taking and conflict network via cognitive control. Additionally, less negative connection density between the social and conflict networks was directly associated with higher CU traits. Our results support the growing literature on cognitive control's influence on socio-cognitive functioning in CU traits and extends that work by identifying underlying functional brain properties.

Affective theory of mind impairments underlying callous-unemotional traits and the role of cognitive control

Affective theory of mind (aToM) impairments associated with the youth antisocial phenotype callous-unemotional (CU) traits predict antisocial behaviour above CU traits alone. Importantly, CU traits associate with decrements in complex but not basic aToM. aToM is modulated by cognitive control and CU traits associate with cognitive control impairments; thus, cognitive control is a plausible mechanism underlying aToM impairments in CU traits. Because cognitive control is dependent on the availability of cognitive resources, youth with CU traits may have difficulty with allocating cognitive resources under greater demands that impact complex aToM. To test this, 81 participants (ages 12-14, Female = 51.8%, Male = 48.2%) were recruited to complete a behavioural paradigm that involved an initial aToM task with complex and basic emotions followed by placing additional demands on cognitive control and a final repeat of the same aToM task. Results indicate adolescents higher in CU traits had intact basic aToM but less accuracy in complex aToM that worsened after taxing cognitive control; and this load only required a short duration to account for ToM decrements (200 ms [range 150-1600 ms]). These results demonstrate CU traits association with cognitive control limitations that impact complex aToM. This may partially explain antisocial behaviour associated with CU traits.

Resting-state network topology characterizing callous-unemotional traits in adolescence

BACKGROUND

Callous-unemotional (CU) traits, a youth antisocial phenotype, are hypothesized to associate with aberrant connectivity (dis-integration) across the salience (SAL), default mode (DMN), and frontoparietal (FPN) networks. However, CU traits have a heterogeneous presentation and previous research has not modeled individual heterogeneity in resting-state connectivity amongst adolescents with CU traits. The present study models individual-specific network maps and examines topological features of individual and subgroup maps in relation to CU traits.

METHODS

Participants aged 13-17 (n = 84, male = 55%, female = 45%) completed resting-state functional connectivity and the inventory of callous-unemotional traits as part of the Nathan Klein Rockland study. A sparse network approach (GIMME) was used to derive individual-level and subgroup maps of all participants. We then examined heterogeneous network features, including positive and negative connection density, associated with CU traits.

RESULTS

Higher rates of CU traits increased probability of inclusion in one subgroup, which had the highest mean level of CU traits. Analysis of network features reveals less density (positive and negative) within the FPN and greater density between DMN-FPN associated with CU traits.

DISCUSSION

Findings indicate heterogeneous person-specific connections and some subgroup connections amongst adolescents associate with CU traits. Higher CU traits associate with lower density in the FPN, which has been associated with attention and inhibition, and higher density between the DMN-FPN, which have been linked with cognitive control, social working memory, and empathy. Our findings suggest less efficiency in FPN function which, when considered mechanistically, could result in difficulty suppressing DMN when task positive networks are engaged. This is an area for further exploration but could explain cognitive and socio-affective impairments in CU traits.

Conduct Disorders and Empathy Development

Childhood conduct disorders, a serious mental health concern, put children at risk for significant mental health problems throughout development. Elevations on callous-unemotional (CU) traits designate a subgroup of youth with conduct disorders who have unique causal processes underlying their problem behavior and are at a particularly high risk for serious impairment relative to others with these disorders. As a result, these traits have recently been integrated into major diagnostic classification systems for conduct disorders. Given that CU traits are partly defined by deficits in empathy, we review research on empathy development in typically developing children and use this research to (a) advance theories on the specific emotional deficits that may be associated with CU traits, (b) explain the severe pattern of aggressive behavior displayed by children with elevated CU traits, and (c) suggest possible ways to enhance prevention and treatment for children with conduct disorders and elevated CU traits.

Callous and uncaring traits are associated with reductions in amygdala volume among youths with varying levels of conduct problems

BACKGROUND

The emergence of callous unemotional (CU) traits, and associated externalizing behaviors, is believed to reflect underlying dysfunction in the amygdala. Studies of adults with CU traits or psychopathy have linked characteristic patterns of amygdala dysfunction to reduced amygdala volume, but studies in youths have not thus far found evidence of similar amygdala volume reductions. The current study examined the association between CU traits and amygdala volume by modeling CU traits and externalizing behavior as independent continuous variables, and explored the relative contributions of callous, uncaring, and unemotional traits.

METHODS

CU traits and externalizing behavior problems were assessed in 148 youths using the Inventory of Callous Unemotional Traits (ICU) and the Child Behavior Checklist (CBCL). For a subset of participants (n = 93), high-resolution T1-weighted images were collected and volume estimates for the amygdala were extracted.

RESULTS

Analyses revealed that CU traits were associated with increased externalizing behaviors and decreased bilateral amygdala volume. These results were driven by the callous and uncaring sub-factors of CU traits, with unemotional traits unrelated to either externalizing behaviors or amygdala volume. Results persisted after accounting for covariation between CU traits and externalizing behaviors. Bootstrap mediation analyses indicated that CU traits mediated the relationship between reduced amygdala volume and externalizing severity.

CONCLUSIONS

These findings provide evidence that callous-uncaring traits account for reduced amygdala volume among youths with conduct problems. These findings provide a framework for further investigation of abnormal amygdala development as a key causal pathway for the development of callous-uncaring traits and conduct problems.

The Reliability and Validity of the Inventory of Callous Unemotional Traits: A Meta-Analytic Review

In the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, a Limited Prosocial Emotions specifier was added to the conduct disorder diagnostic criteria to designate a subgroup of children who exhibit callous unemotional (CU) traits. The Inventory of Callous Unemotional Traits (ICU) is the only dedicated measure of CU traits and was influential in the development of the Limited Prosocial Emotions specifier. Despite its role in the research and diagnosis of CU traits, some questions have persisted regarding the internal consistency and validity of the ICU and its three subscales: callous, uncaring, and unemotional. Results of a meta-analysis revealed acceptable internal consistency and external validity for total ICU, callous, and uncaring scores, but not unemotional scores. These results support the utility of the total ICU, callous, and uncaring scales, but indicate weaknesses in the scale or construct of unemotionality as it relates to interpersonal callousness, uncaring, and antisociality.

Attention to emotion through a go/no-go task in children with oppositionality and callous-unemotional traits

BACKGROUND

There is debate about whether the difficulties that children with different degrees of oppositionality (ODD) and callous-unemotional traits (CU) have in processing emotions are global or specific. The aim of this study is to identify difficulties in recognizing emotion (happiness, anger, sadness and fear) through a go/no-go task in children with different levels of ODD and CU traits.

METHOD

A total of 320 8-year-old children were assessed through questionnaires filled out by teachers about oppositional defiant symptoms and CU traits and were then distributed into four groups: LowCU-HighODD, HighCU-LowODD, HighCU-HighODD and a comparison group (LowCU-LowODD).

RESULTS

The analyses of variance comparing the 4 groups showed that the two groups with high ODD were less accurate than the control group in recognizing the emotion when the stimuli expressed happiness, fear or neutral emotion. The HighCU-HighODD group differed in the quality of the response (correct/wrong responses) but not in the reaction time in relation to the comparison group. The LowCU-HighODD group was faster to respond to emotions than the comparison group.

IMPLICATIONS

The results show that the deficit in emotion processing is not restricted to specific distressing emotions such as fear or sadness, but they point to a global impairment in emotion processing in children scoring high in the constructs studied. The results also suggest that the difficulties that children with combined CU traits and oppositional conduct problems have in processing emotions are more of an emotional rather than an attentional nature.