TY  - JOUR
A1  - Likowski, Katja U.
A1  - Mühlberger, Andreas
A1  - Gerdes, Antje B. M.
A1  - Wieser, Mattias J.
A1  - Pauli, Paul
A1  - Weyers, Peter
T1  - Facial mimicry and the mirror neuron system: simultaneous acquisition of facial electromyography and functional magnetic resonance imaging
N2  - Numerous studies have shown that humans automatically react with congruent facial reactions, i.e., facial mimicry, when seeing a vis-á-vis’ facial expressions. The current experiment is the first investigating the neuronal structures responsible for differences in the occurrence of such facial mimicry reactions by simultaneously measuring BOLD and facial EMG in an MRI scanner. Therefore, 20 female students viewed emotional facial expressions (happy, sad, and angry) of male and female avatar characters. During picture presentation, the BOLD signal as well as M. zygomaticus major and M. corrugator supercilii activity were recorded simultaneously. Results show prototypical patterns of facial mimicry after correction for MR-related artifacts: enhanced M. zygomaticus major activity in response to happy and enhanced M. corrugator supercilii activity in response to sad and angry expressions. Regression analyses show that these congruent facial reactions correlate significantly with activations in the IFG, SMA, and cerebellum. Stronger zygomaticus reactions to happy faces were further associated to increased activities in the caudate, MTG, and PCC. Corrugator reactions to angry expressions were further correlated with the hippocampus, insula, and STS. Results are discussed in relation to core and extended models of the mirror neuron system (MNS).
KW  - Psychologie
KW  - mimicry
KW  - EMG
KW  - fMRI
KW  - mirrorneuronsystem
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75813
ER  - 
TY  - JOUR
A1  - Ewald, Heike
A1  - Glotzbach-Schoon, Evelyn
A1  - Gerdes, Antje B. M.
A1  - Andreatta, Marta
A1  - Müller, Mathias
A1  - Mühlberger, Andreas
A1  - Pauli, Paul
T1  - Delay and trace fear conditioning in a complex virtual learning environment - neural substrates of extinction
JF  - Frontiers in Human Neuroscience
N2  - Extinction is an important mechanism to inhibit initially acquired fear responses. There is growing evidence that the ventromedial prefrontal cortex (vmPFC) inhibits the amygdala and therefore plays an important role in the extinction of delay fear conditioning. To our knowledge, there is no evidence on the role of the prefrontal cortex in the extinction of trace conditioning up to now. Thus, we compared brain structures involved in the extinction of human delay and trace fear conditioning in a between-subjects-design in an fMRI study. Participants were passively guided through a virtual environment during learning and extinction of conditioned fear. Two different lights served as conditioned stimuli (CS); as unconditioned stimulus (US) a mildly painful electric stimulus was delivered. In the delay conditioning group (DCG) the US was administered with offset of one light (CS+), whereas in the trace conditioning group (TCG) the US was presented 4s after CS+ offset. Both groups showed insular and striatal activation during early extinction, but differed in their prefrontal activation. The vmPFC was mainly activated in the DCG, whereas the TCG showed activation of the dorsolateral prefrontal cortex (dlPFC) during extinction. These results point to different extinction processes in delay and trace conditioning. VmPFC activation during extinction of delay conditioning might reflect the inhibition of the fear response. In contrast, dlPFC activation during extinction of trace conditioning may reflect modulation of working memory processes which are involved in bridging the trace interval and hold information in short term memory.
KW  - prefrontal cortex
KW  - delay conditioning
KW  - trace conditioning
KW  - extinction
KW  - virtual reality
KW  - fMRI
KW  - medial prefrontal cortex
KW  - event-related FMRI
KW  - orbifrontal cortex
KW  - contextual fear
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-116230
SN  - 1662-5161
VL  - 8
IS  - 323
ER  -