New research has revealed distinct patterns of brain connectivity in adolescents with two subtypes of tough, non-emotional traits. The study found unique neurobiological features in these two variants, with behavioral problems mediating the relationship between cruelty and specific brain connections associated with social and emotional processing. The results have been published in Journal of Psychiatric Research.
Hard, unemotional traits are characterized by low levels of guilt, empathy, and concern for others. Children with these traits often display a lack of emotional response and interpersonal behaviours. These features are similar to the emotional and interpersonal deficits that characterize adult psychopathy.
There are two basic subsets of tough, non-emotional traits: the primary variant (low anxiety) and the secondary variant (high anxiety). The researchers aimed to study differences in brain connectivity patterns between adolescents who display these two subgroups. Specifically, they were interested in exploring whether these variants of tough, non-emotional traits were associated with distinct patterns of connectivity in the amygdala, a brain region that plays an important role in emotional processing.
“The importance of this topic stems from the common assumption that children with high callous and unemotional traits form a unified group characterized mainly by deficits in amygdala activity,” said study author Jules Roger Dugery.@Jul_Dugre) from the University of Birmingham. However, extensive research spanning decades suggests that anxiety severity may underlie clinical subtypes among individuals with high callous and unemotional traits, that is, those with clinical levels of anxiety (the secondary variable) and no clinical levels of anxiety. Anxiety (primary variable).”
The study included data from 1,416 young adults, collected from the Brain Health Network initiative in the New York area. Data on cruelty, anxiety, behavior problems, and negative life events were collected through parent-reported evaluations. These participants also underwent functional neuroimaging examinations.
By conducting a latent profile analysis, the researchers identified four distinct subgroups with varying levels of callousness and severity of anxiety: anxiety (anxiety high, cruelty low), normally developing (low anxiety, low harshness), The primary alternative to psychopathy (low anxiety, high cruelty), f The secondary variant of psychopathy (severe anxiety, high severity).
The underlying variant was characterized by increased connectivity between the left amygdala and the left thalamus (dorsal medial nucleus), likely related to difficulties in adapting behaviors when reinforcement values change.
The secondary variable showed deficits in connectivity between the amygdala and different regions, including the posterior superior temporal sulcus/temporal-parietal junction (pSTS/TPJ), the postcentral gyrus (PoCG), and the dorsomedial prefrontal cortex (dmPFC), suggesting impairment More intentional.
When comparing primary and secondary variables, the researchers also revealed common and distinct neurobiological features associated with the functional connectivity of the amygdala.
Both options showed altered functional connectivity between the left amygdala and right thalamus, suggesting a common neurobiological feature compared to the normally developing group. However, primary and secondary variants showed opposite functional connectivity between the amygdala and the left parahippocampal gyrus/fusiform gyrus (PHG/FF). The primary variable showed an increase in contact, while the secondary variable showed a decrease in contact.
Among the adolescents who displayed high levels of cruelty, the severity of the behavior problems seemed to act as a mediator between the cruelty and the functional connection between the amygdala and the dmPFC. In other words, behavioral problems seem to play a role in influencing the strength of connectivity between these brain regions, which are known to be involved in social and emotional processing and regulation.
“The main takeaway from this study is that children, with or without clinical levels of anxiety, showed differences in how the amygdala interacted with regions of the brain responsible for sensory and emotional memory processes,” Dughry told PsyPost. “Furthermore, our findings suggest that the extent of behavioral problems (such as aggression and rule-breaking behaviors) played a mediating role in the relationship between toughness and connectivity between the amygdala and dorsolateral prefrontal cortex, which is typically associated with resilience.” To understand the mental states of others.”
“It is clear that more research should aim to replicate these findings using diverse samples, such as in young offenders,” Dugrey said. “While primary and secondary variants are subtypes that received relatively strong validation, previous studies have indicated that additional clinical features (such as irritability and ADHD symptoms) could also contribute to significant heterogeneity within this population. Therefore, our study underscores the importance of examining the commonalities and differences in neurobiological substrates among different groups of children at risk for behavior problems.
the study, “Altering functional connectivity of the amygdala across tough, non-emotional trait variables: a resting-state fMRI study in children and adolescents.Written by Jules R. Dugré and Stéphane Potvin.