Background: High levels of aggressive behavior are associated with a low resting heart rate in boys. However, differences in underlying mechanisms, e.g. arousal levels, might exist between boys...Show moreBackground: High levels of aggressive behavior are associated with a low resting heart rate in boys. However, differences in underlying mechanisms, e.g. arousal levels, might exist between boys with disruptive behavior disorders, which might have implications for intervention programs to prevent aggressive behavior to develop further into adulthood. Methods: The current study investigated resting heart rate (beats per minute) and skin conductance levels (μS ) in boys, 8-12 years old (Mage = 9.67, SD = 1.18), with a disruptive behavior disorder (NDBD= 24, NControl = 25). Levels of anxiety and characteristics of an autism spectrum disorder were considered as co-occuring symptoms, to consider possible differences between the two groups and to infer the predictive value of these symptoms regarding arousal levels. Arousal levels in resting state were considered while the participants watched a three minute calming video of fishes. Levels of aggression, anxiety and amount of characteristics of an autism spectrum disorder were measured by questionnaires that were administered by the boys themselves (MASC) and the parents (ASEBA CBCL 6-18 and VISK). One-way analyses of variance were performed to infer possible differences between the control group and the DBD group. Moreover, multiple regression analyses were executed to consider the predictive value of the levels of the mentioned symptoms with regard to arousal levels. Results: No differences were found in arousal measures in resting state between the DBD group and the control group. However, expressing higher levels of characteristics of autism, especially not understanding social information (e.g. jokes), stereotypic behavior and anxiety for change, turned out to be partly predictive for higher levels of heart rate in the DBD group. None of the considered factors was predictive for variation in skin conductance levels in this group. Conclusions: The current findings suggest that some of the aggression seen in the DBD group could possibly origin from the lack of understanding as well as anxiety or tension with regard to social situations and is associated with somewhat higher levels of arousal instead of lower levels, as previously suggested. The tentative findings in the current study could incite to investigate in more depth the predictors of variation in levels of arousal, which could provide more information about differences between individuals with regard to underlying mechanisms of aggression.Show less
