TY  - JOUR
A1  - Ventura-Bort, Carlos
A1  - Dolcos, Florin
A1  - Wendt, Julia
A1  - Wirkner, Janine
A1  - Hamm, Alfons O.
A1  - Weymar, Mathias
T1  - Item and source memory for emotional associates is mediated by different retrieval processes
JF  - Neuropsychologia : an international journal in behavioural and cognitive neuroscience
N2  - Recent event-related potential (ERP) data showed that neutral objects encoded in emotional background pictures were better remembered than objects encoded in neutral contexts, when recognition memory was tested one week later. In the present study, we investigated whether this long-term memory advantage for items is also associated with correct memory for contextual source details. Furthermore, we were interested in the possibly dissociable contribution of familiarity and recollection processes (using a Remember/Know procedure). The results revealed that item memory performance was mainly driven by the subjective experience of familiarity, irrespective of whether the objects were previously encoded in emotional or neutral contexts. Correct source memory for the associated background picture, however, was driven by recollection and enhanced when the content was emotional. In ERPs, correctly recognized old objects evoked frontal ERP Old/New effects (300-500 ms), irrespective of context category. As in our previous study (Ventura-Bort et al., 2016b), retrieval for objects from emotional contexts was associated with larger parietal Old/New differences (600-800 ms), indicating stronger involvement of recollection. Thus, the results suggest a stronger contribution of recollection-based retrieval to item and contextual background source memory for neutral information associated with an emotional event.
KW  - event-related potentials
KW  - emotion
KW  - source memory
KW  - remember/know
KW  - old/new
KW  - effect
Y1  - 2017
U6  - https://doi.org/10.1016/j.neuropsychologia.2017.12.015
SN  - 0028-3932
SN  - 1873-3514
VL  - 145
PB  - Elsevier
CY  - Oxford
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  - 
TY  - GEN
A1  - Weymar, Mathias
A1  - Ventura-Bort, Carlos
A1  - Genheimer, Hannah
A1  - Wirkner, Janine
A1  - Wendt, Julia
A1  - Hamm, Alfons O.
T1  - THE P300 AND THE LC-NE SYSTEM: NEW INSIGHTS FROM TRANSCUTANEOUS VAGUS NERVE STIMULATION (TVNS)
T2  - Psychophysiology : journal of the Society for Psychophysiological Research
KW  - P300
KW  - norepinephrine
KW  - transcutaneous vagus nerve stimulation
Y1  - 2017
SN  - 0048-5772
SN  - 1469-8986
VL  - 54
SP  - S145
EP  - S145
PB  - Wiley
CY  - Hoboken
ER  -