@article{GerdesWieserMuehlbergeretal.2010,
  author    = {Gerdes, Antje B. M. and Wieser, Matthias J. and M{\"u}hlberger, Andreas and Weyers, Peter and Alpers, Georg W. and Plichta, Michael M. and Breuer, Felix and Pauli, Paul},
  title     = {Brain activations to emotional pictures are differentially associated with valence and arousal ratings},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68153},
  year      = {2010},
  abstract  = {Several studies have investigated the neural responses triggered by emotional pictures, but the specificity of the involved structures such as the amygdala or the ventral striatum is still under debate. Furthermore, only few studies examined the association of stimuli's valence and arousal and the underlying brain responses. Therefore, we investigated brain responses with functional magnetic resonance imaging of 17 healthy participants to pleasant and unpleasant affective pictures and afterwards assessed ratings of valence and arousal. As expected, unpleasant pictures strongly activated the right and left amygdala, the right hippocampus, and the medial occipital lobe, whereas pleasant pictures elicited significant activations in left occipital regions, and in parts of the medial temporal lobe. The direct comparison of unpleasant and pleasant pictures, which were comparable in arousal clearly indicated stronger amygdala activation in response to the unpleasant pictures. Most important, correlational analyses revealed on the one hand that the arousal of unpleasant pictures was significantly associated with activations in the right amygdala and the left caudate body. On the other hand, valence of pleasant pictures was significantly correlated with activations in the right caudate head, extending to the nucleus accumbens (NAcc) and the left dorsolateral prefrontal cortex. These findings support the notion that the amygdala is primarily involved in processing of unpleasant stimuli, particularly to more arousing unpleasant stimuli. Reward-related structures like the caudate and NAcc primarily respond to pleasant stimuli, the stronger the more positive the valence of these stimuli is.},
  subject      = {Psychologie},
  language  = {en}
}
@article{SchwarzWieserGerdesetal.2013,
  author    = {Schwarz, Katharina A. and Wieser, Matthias J. and Gerdes, Antje B. M. and M{\"u}hlberger, Andreas and Pauli, Paul},
  title     = {Why are you looking like that? How the context influences evaluation and processing of human faces},
  series = {Social Cognitive and Affective Neuroscience},
  volume    = {8},
  journal   = {Social Cognitive and Affective Neuroscience},
  number    = {4},
  doi       = {10.1093/scan/nss013},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-132126},
  pages     = {438-445},
  year      = {2013},
  abstract  = {Perception and evaluation of facial expressions are known to be heavily modulated by emotional features of contextual information. Such contextual effects, however, might also be driven by non-emotional aspects of contextual information, an interaction of emotional and non-emotional factors, and by the observers' inherent traits. Therefore, we sought to assess whether contextual information about self-reference in addition to information about valence influences the evaluation and neural processing of neutral faces. Furthermore, we investigated whether social anxiety moderates these effects. In the present functional magnetic resonance imaging (fMRI) study, participants viewed neutral facial expressions preceded by a contextual sentence conveying either positive or negative evaluations about the participant or about somebody else. Contextual influences were reflected in rating and fMRI measures, with strong effects of self-reference on brain activity in the medial prefrontal cortex and right fusiform gyrus. Additionally, social anxiety strongly affected the response to faces conveying negative, self-related evaluations as revealed by the participants' rating patterns and brain activity in cortical midline structures and regions of interest in the left and right middle frontal gyrus. These results suggest that face perception and processing are highly individual processes influenced by emotional and non-emotional aspects of contextual information and further modulated by individual personality traits.},
  language  = {en}
}
@article{EwaldGlotzbachSchoonGerdesetal.2014,
  author    = {Ewald, Heike and Glotzbach-Schoon, Evelyn and Gerdes, Antje B. M. and Andreatta, Marta and M{\"u}ller, Mathias and M{\"u}hlberger, Andreas and Pauli, Paul},
  title     = {Delay and trace fear conditioning in a complex virtual learning environment - neural substrates of extinction},
  series = {Frontiers in Human Neuroscience},
  volume    = {8},
  journal   = {Frontiers in Human Neuroscience},
  number    = {323},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2014.00323},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-116230},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}
@article{LikowskiMuehlbergerGerdesetal.2012,
  author    = {Likowski, Katja U. and M{\"u}hlberger, Andreas and Gerdes, Antje B. M. and Wieser, Mattias J. and Pauli, Paul and Weyers, Peter},
  title     = {Facial mimicry and the mirror neuron system: simultaneous acquisition of facial electromyography and functional magnetic resonance imaging},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75813},
  year      = {2012},
  abstract  = {Numerous studies have shown that humans automatically react with congruent facial reactions, i.e., facial mimicry, when seeing a vis-{\´a}-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).},
  subject      = {Psychologie},
  language  = {en}
}