Behavioral Inhibition and Risk for Developing Social Anxiety Disorder: A Meta-Analytic Study

Children with an anxious temperament (AT) are at risk for developing psychiatric disorders along the internalizing spectrum, including anxiety and depression. Like these disorders, AT is a multidimensional phenotype and children with extreme anxiety show varying mixtures of physiological, behavioral, and other symptoms. Using a well-validated juvenile monkey model of AT, we addressed the degree to which this phenotypic heterogeneity reflects fundamental differences or similarities in the underlying neurobiology. The rhesus macaque is optimal for studying AT because children and young monkeys express the anxious phenotype in similar ways and have similar neurobiology. Fluorodeoxyglucose (FDG)-positron emission tomography (FDG-PET) in 238 freely behaving monkeys identified brain regions where metabolism predicted variation in three dimensions of the AT phenotype: hypothalamic-pituitaryadrenal (HPA) activity, freezing behavior, and expressive vocalizations. We distinguished brain regions that predicted all three dimensions of the phenotype from those that selectively predicted a single dimension. Elevated activity in the central nucleus of the amygdala and the anterior hippocampus was consistently found across individuals with different presentations of AT. In contrast, elevated activity in the lateral anterior hippocampus was selective to individuals with high levels of HPA activity, and decreased activity in the motor cortex (M1) was selective to those with high levels of freezing behavior. Furthermore, activity in these phenotype-selective regions mediated relations between amygdala metabolism and different expressions of anxiety. These findings provide a framework for understanding the mechanisms that lead to heterogeneity in the clinical presentation of internalizing disorders and set the stage for developing improved interventions.affective neuroscience | behavioral inhibition | developmental psychopathology | emotion | functional neuroimaging

The objective of this narrative review of the literature is to describe the epidemiology, etiology, pathophysiology, diagnosis, and treatment of pediatric anxiety disorders. We aim to guide clinicians in understanding the biology of anxiety disorders and to provide general guidelines for the proper diagnoses and treatment of these conditions early in life. Anxiety disorders are prevalent, associated with a number of negative life outcomes, and currently under-recognized and under-treated. The etiology involves both genes and environmental influences modifying the neural substrate in a complex interplay. Research on pathophysiology is still in its infancy, but some brain regions, such as the amygdala and the prefrontal cortex, have been implicated in fear and anxiety. Current practice is to establish diagnosis based purely on clinical features, derived from clinical interviews with the child, parents, and teachers. Treatment is effective using medication, cognitive behavioral therapy, or a combination of both. An introduction to the neuroscience behind anxiety disorders combined with an evidence-based approach may help clinicians to understand these disorders and treat them properly in childhood.

Attention-Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that begins to emerge in childhood. This disorder is caused by an impaired prefrontal cortex (PFC) development that affects executive functions, particularly in inhibition, resulting in loss of cognitive and behavior control. This research aims to investigate the difference between inhibition in ADHD and non-ADHD children ages 6-12 years old and between the three subtypes of ADHD. Subjects in this study were children with ADHD (N=34) which consists of the inattentive type (N=14), hyperactive-impulsive type (N=9), and combination type (N=11), as well as non-ADHD children (N=34). This research used the causal-comparative method. The instrument which was utilized in this study is The Stroop Color and Word test to measure inhibition. Results of this research showed that there are differences in inhibition between ADHD and non-ADHD children and between age 6-9 years and 10-12 years old children. However, there is no difference of inhibition between three subtypes of ADHD.