@article{PeperkornDiemerAlpersetal.2016,
  author    = {Peperkorn, Henrik M. and Diemer, Julia E. and Alpers, Georg W. and M{\"u}hlberger, Andreas},
  title     = {Representation of Patients' Hand Modulates Fear Reactions of Patients with Spider Phobia in Virtual Reality},
  series = {frontiers in Psychology},
  volume    = {7},
  journal   = {frontiers in Psychology},
  number    = {268},
  doi       = {10.3389/fpsyg.2016.00268},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165307},
  year      = {2016},
  abstract  = {Embodiment (i.e., the involvement of a bodily representation) is thought to be relevant in emotional experiences. Virtual reality (VR) is a capable means of activating phobic fear in patients. The representation of the patient's body (e.g., the right hand) in VR enhances immersion and increases presence, but its effect on phobic fear is still unknown. We analyzed the influence of the presentation of the participant's hand in VR on presence and fear responses in 32 women with spider phobia and 32 matched controls. Participants sat in front of a table with an acrylic glass container within reaching distance. During the experiment this setup was concealed by a head-mounted display (HMD). The VR scenario presented via HMD showed the same setup, i.e., a table with an acrylic glass container. Participants were randomly assigned to one of two experimental groups. In one group, fear responses were triggered by fear-relevant visual input in VR (virtual spider in the virtual acrylic glass container), while information about a real but unseen neutral control animal (living snake in the acrylic glass container) was given. The second group received fear-relevant information of the real but unseen situation (living spider in the acrylic glass container), but visual input was kept neutral VR (virtual snake in the virtual acrylic glass container). Participants were instructed to touch the acrylic glass container with their right hand in 20 consecutive trials. Visibility of the hand was varied randomly in a within-subjects design. We found for all participants that visibility of the participant's hand increased presence independently of the fear trigger. However, in patients, the influence of the virtual hand on fear depended on the fear trigger. When fear was triggered perceptually, i.e., by a virtual spider, the virtual hand increased fear. When fear was triggered by information about a real spider, the virtual hand had no effect on fear. Our results shed light on the significance of different fear triggers (visual, conceptual) in interaction with body representations.},
  language  = {en}
}
@article{WalzMuehlbergerPauli2016,
  author    = {Walz, Nora and M{\"u}hlberger, Andreas and Pauli, Paul},
  title     = {A human open field test reveals thigmotaxis related to agoraphobic fear},
  series = {Biological Psychiatry},
  volume    = {80},
  journal   = {Biological Psychiatry},
  number    = {5},
  doi       = {10.1016/j.biopsych.2015.12.016},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-187607},
  pages     = {390-397},
  year      = {2016},
  abstract  = {BACKGROUND: Thigmotaxis refers to a specific behavior of animals (i.e., to stay close to walls when exploring an open space). Such behavior can be assessed with the open field test (OFT), which is a well-established indicator of animal fear. The detection of similar open field behavior in humans may verify the translational validity of this paradigm. Enhanced thigmotaxis related to anxiety may suggest the relevance of such behavior for anxiety disorders, especially agoraphobia. METHODS: A global positioning system was used to analyze the behavior of 16 patients with agoraphobia and 18 healthy individuals with a risk for agoraphobia (i.e., high anxiety sensitivity) during a human OFT and compare it with appropriate control groups (n = 16 and n = 19). We also tracked 17 patients with agoraphobia and 17 control participants during a city walk that involved walking through an open market square. RESULTS: Our human OFT triggered thigmotaxis in participants; patients with agoraphobia and participants with high anxiety sensitivity exhibited enhanced thigmotaxis. This behavior was evident in increased movement lengths along the wall of the natural open field and fewer entries into the center of the field despite normal movement speed and length. Furthermore, participants avoided passing through the market square during the city walk, indicating again that thigmotaxis is related to agoraphobia. CONCLUSIONS: This study is the first to our knowledge to verify the translational validity of the OFT and to reveal that thigmotaxis, an evolutionarily adaptive behavior shown by most species, is related to agoraphobia, a pathologic fear of open spaces, and anxiety sensitivity, a risk factor for agoraphobia.},
  language  = {en}
}
@article{AsthanaBrunhuberMuehlbergeretal.2016,
  author    = {Asthana, Manish Kumar and Brunhuber, Bettina and M{\"u}hlberger, Andreas and Reif, Andreas and Schneider, Simone and Herrmann, Martin J.},
  title     = {Preventing the Return of Fear Using Reconsolidation Update Mechanisms Depends on the Met-Allele of the Brain Derived Neurotrophic Factor Val66Met Polymorphism},
  series = {International Journal of Neuropsychopharmacology},
  volume    = {19},
  journal   = {International Journal of Neuropsychopharmacology},
  number    = {6},
  doi       = {10.1093/ijnp/pyv137},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166217},
  year      = {2016},
  abstract  = {Background: Memory reconsolidation is the direct effect of memory reactivation followed by stabilization of newly synthesized proteins. It has been well proven that neural encoding of both newly and reactivated memories requires synaptic plasticity. Brain derived neurotrophic factor (BDNF) has been extensively investigated regarding its role in the formation of synaptic plasticity and in the alteration of fear memories. However, its role in fear reconsolidation is still unclear; hence, the current study has been designed to investigate the role of the BDNF val66met polymorphism (rs6265) in fear memory reconsolidation in humans. Methods: An auditory fear-conditioning paradigm was conducted, which comprised of three stages (acquisition, reactivation, and spontaneous recovery). One day after fear acquisition, the experimental group underwent reactivation of fear memory followed by the extinction training (reminder group), whereas the control group (non-reminder group) underwent only extinction training. On day 3, both groups were subjected to spontaneous recovery of earlier learned fearful memories. The treat-elicited defensive response due to conditioned threat was measured by assessing the skin conductance response to the conditioned stimulus. All participants were genotyped for rs6265. Results: The results indicate a diminishing effect of reminder on the persistence of fear memory only in the Met-allele carriers, suggesting a moderating effect of the BDNF polymorphism in fear memory reconsolidation. Conclusions: Our findings suggest a new role for BDNF gene variation in fear memory reconsolidation in humans.},
  language  = {en}
}