@article{WendtLoewWeymaretal.2017, author = {Wendt, Julia and Loew, Andreas and Weymar, Mathias and Lotze, Martin and Hamm, Alfons O.}, title = {Active avoidance and attentive freezing in the face of approaching threat}, series = {NeuroImage : a journal of brain function}, volume = {158}, journal = {NeuroImage : a journal of brain function}, publisher = {Elsevier}, address = {San Diego}, issn = {1053-8119}, doi = {10.1016/j.neuroimage.2017.06.054}, pages = {196 -- 204}, year = {2017}, abstract = {Defensive behaviors in animals and humans vary dynamically with increasing proximity of a threat and depending upon the behavioral repertoire at hand. The current study investigated physiological and behavioral adjustments and associated brain activation when participants were exposed to dynamically approaching threat that was either inevitable or could be avoided by motor action. When the approaching threat was inevitable, attentive freezing was observed as indicated by fear bradycardia, startle potentiation, and a dynamic increase in activation of the anterior insula and the periaqueductal grey. In preparation for active avoidance a switch in defensive behavior was observed characterized by startle inhibition and heart rate acceleration along with potentiated activation of the amygdala and the periaqueductal grey. Importantly, the modulation of defensive behavior according to threat imminence and the behavioral option at hand was associated with activity changes in the ventromedial prefrontal cortex. These findings improve our understanding of brain mechanisms guiding human behavior during approaching threat depending on available resources.}, language = {en} } @article{SchinkoethWeymarBrand2019, author = {Schink{\"o}th, Michaela and Weymar, Mathias and Brand, Ralf}, title = {Listening to the heart}, series = {Psychology of sport and exercise}, volume = {45}, journal = {Psychology of sport and exercise}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1469-0292}, doi = {10.1016/j.psychsport.2019.101541}, pages = {4}, year = {2019}, abstract = {Objective: The affective-reflective theory of physical inactivity and exercise suggests that the mere thought of exercise can lead to an immediate somato-affective response which, if negative, will drive a physically inactive person to maintain his or her current exercise-avoidant behavior. This study aimed to test the assumption that the somatic core of this affective response can be identified by means of heart rate variability (HRV) analysis. Design: This study followed a within-subject experimental design. Method. Participants were 91 adult men and women whose HR and HRV were monitored whilst they viewed exercise-related and control pictures in a laboratory setting. Results: Analyses revealed a decrease in HRV during the viewing of exercise-related pictures in less physically active participants. These participants reported that the same pictures elicited feelings with relatively low affective valence and arousal. There were no changes in HR.}, language = {en} }