Early Childhood Aggression in Autistic and Non-Autistic Preschoolers: Prevalence, Topography, and Relationship to Emotional Reactivity.

Objective: Despite heightened rates of aggressive behaviors among older autistic youth relative to non-autistic peers, less is known about these behaviors during early childhood. This study included 3 objectives to address this gap: (1) to establish the prevalence and topography (frequency, severity, type, context) of aggressive behaviors in a large sample of preschool-aged children using a developmentally sensitive parent-report measure; (2) to identify clinical correlates of aggression; and (3) to investigate whether different subgroups of autistic children can be identified based on their profiles of aggression, emotional reactivity, and autism traits.

Method: Data were analyzed from parents of 1,199 children 2 to 5 years of age (n = 622 autistic children) who completed the Multidimensional Assessment Profiles Scales (MAPS) aggression subscale and the Emotion Dysregulation Inventory-Young Child (EDI-YC) reactivity subscale.

Interaction between corticosterone and PER2 in regulating emotional behaviors in the rat.

Circadian rhythms play a prominent role in psychiatric health with disruption in rhythms associated with poor mental health. Corticosterone (CORT) is an important hormone in entraining the biological rhythms of many cells throughout the body and coordinating peripheral rhythms with the central master clock. Here, we tested the hypothesis that excess CORT during the circadian trough would lead to a flattening of period genes (Per1 and Per2) rhythms in limbic brain areas, and thus impact emotional behaviors.

Sympathetic nervous system contributes to enhanced corticosterone levels following chronic stress.

Exposure to chronic stress often elevates basal circulating glucocorticoids during the circadian nadir and leads to exaggerated glucocorticoid production following exposure to subsequent stressors. While glucocorticoid production is primarily mediated by the hypothalamic-pituitary-adrenal (HPA) axis, there is evidence that the sympathetic nervous system can affect diurnal glucocorticoid production by direct actions at the adrenal gland. Experiments here were designed to examine the role of the HPA and sympathetic nervous system in enhancing corticosterone production following chronic stress.