Negative cognitive emotion regulation as a predictor of adolescent heart rate variability and entropy under social stress.

<bold>Background and Objectives: </bold>Negative cognitive emotion regulation (ER) strategies are particularly important within the framework of anxiety problems amongst youths and how they cope with stressful events. The aim of this study was to examine the associations between both negative and positive ER style and cardiac regulation under stressful conditions.<bold>Design: </bold>Eighty-nine adolescents (M = 13.31 years, SD = 0.68, 44.94% girls) were exposed to a socially relevant stress induction protocol.<bold>Methods: </bold>Participants' emotion regulation strategies were assessed and their cardiac function was recorded.<bold>Results: </bold>A negative ER style predicted heart rate (HR) entropy at the stressful stage after controlling for anxiety scores. In addition, heart rate variability reactivity and recovery and HR entropy recovery were larger (p < .05) in the low negative ER style group (n = 16) than in the high negative ER style group (n = 23).<bold>Conclusions: </bold>Results suggest that individuals with a highly negative ER style have diminished autonomic flexibility. [ABSTRACT FROM AUTHOR]