Associations between inhibitory control, respiratory sinus arrhythmia, and externalizing problems in early childhood.

Polyvagal theory provides a framework for understanding connections between children's autonomic regulation, cognitive functioning, and behavioral adjustment. Parasympathetic regulation has been associated with executive functions and externalizing problems (EP), and children with EP demonstrate deficits in inhibition of prepotent responding, or inhibitory control (IC). We examined parasympathetic regulation of cardiac reactivity during two IC tasks in 144 children (M = 5.61 years, SD = 1.09) ranging from low to clinical levels of EP. Overall children with more EP evidenced greater RSA suppression during IC tasks than did children with fewer EP, and degree of RSA suppression also moderated associations between IC performance and EP. Only for children who showed stronger RSA suppression was accuracy of IC response inversely associated with EP, and latency of response for one task positively associated with EP. This study provides insight into the role of parasympathetic mechanisms in children's cognitive regulation of impulsive and aggressive behaviors.

The role of the amygdala in emotional processing: a quantitative meta-analysis of functional neuroimaging studies.

Functional neuroimaging studies have provided strong support for a critical role of the amygdala in emotional processing. However, several controversies remain in terms of whether different factors-such as sex, valence and stimulus type-have an effect on the magnitude and lateralization of amygdala responses. To address these issues, we conducted a meta-analysis of functional neuroimaging studies of visual emotional perception that reported amygdala activation. Critically, unlike previous neuroimaging meta-analyses, we took into account the magnitude (effect size) and reliability (variance) associated with each of the activations. Our results confirm that the amygdala responds to both positive and negative stimuli, with a preference for faces depicting emotional expressions. We did not find evidence for amygdala lateralization as a function of sex or valence. Instead, our findings provide strong support for a functional dissociation between left and right amygdala in terms of temporal dynamics. Taken together, results from this meta-analysis shed new light on several of the models proposed in the literature regarding the neural basis of emotional processing.