TY  - JOUR
A1  - Sege, Christopher T.
A1  - Bradley, Margaret M.
A1  - Weymar, Mathias
A1  - Lang, Peter J.
T1  - A direct comparison of appetitive and aversive anticipation
BT  - overlapping and distinct neural activation
JF  - Behavioural brain research : an international journal
N2  - fMRI studies of reward find increased neural activity in ventral striatum and medial prefrontal cortex (mPFC), whereas other regions, including the dorsolateral prefrontal cortex (d1PFC), anterior cingulate cortex (ACC), and anterior insula, are activated when anticipating aversive exposure. Although these data suggest differential activation during anticipation of pleasant or of unpleasant exposure, they also arise in the context of different paradigms (e.g., preparation for reward vs. threat of shock) and participants. To determine overlapping and unique regions active during emotional anticipation, we compared neural activity during anticipation of pleasant or unpleasant exposure in the same participants. Cues signalled the upcoming presentation of erotic/romantic, violent, or everyday pictures while BOLD activity during the 9-s anticipatory period was measured using fMRI. Ventral striatum and a ventral mPFC subregion were activated when anticipating pleasant, but not unpleasant or neutral, pictures, whereas activation in other regions was enhanced when anticipating appetitive or aversive scenes.
KW  - Anticipation
KW  - Emotion
KW  - fMRI
Y1  - 2017
U6  - https://doi.org/10.1016/j.bbr.2017.03.005
SN  - 0166-4328
SN  - 1872-7549
VL  - 326
SP  - 96
EP  - 102
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wendt, Julia
A1  - Loew, Andreas
A1  - Weymar, Mathias
A1  - Lotze, Martin
A1  - Hamm, Alfons O.
T1  - Active avoidance and attentive freezing in the face of approaching threat
JF  - NeuroImage : a journal of brain function
N2  - 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.
KW  - Defensive response patterns
KW  - Active avoidance
KW  - Freezing
KW  - Psychophysiology
KW  - fMRI
Y1  - 2017
U6  - https://doi.org/10.1016/j.neuroimage.2017.06.054
SN  - 1053-8119
SN  - 1095-9572
VL  - 158
SP  - 196
EP  - 204
PB  - Elsevier
CY  - San Diego
ER  -