@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{GromerMadeiraGastetal.2018,
  author    = {Gromer, Daniel and Madeira, Oct{\´a}via and Gast, Philipp and Nehfischer, Markus and Jost, Michael and M{\"u}ller, Mathias and M{\"u}hlberger, Andreas and Pauli, Paul},
  title     = {Height Simulation in a Virtual Reality CAVE System: Validity of Fear Responses and Effects of an Immersion Manipulation},
  series = {Frontiers in Human Neuroscience},
  volume    = {12},
  journal   = {Frontiers in Human Neuroscience},
  number    = {372},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2018.00372},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-196113},
  year      = {2018},
  abstract  = {Acrophobia is characterized by intense fear in height situations. Virtual reality (VR) can be used to trigger such phobic fear, and VR exposure therapy (VRET) has proven effective for treatment of phobias, although it remains important to further elucidate factors that modulate and mediate the fear responses triggered in VR. The present study assessed verbal and behavioral fear responses triggered by a height simulation in a 5-sided cave automatic virtual environment (CAVE) with visual and acoustic simulation and further investigated how fear responses are modulated by immersion, i.e., an additional wind simulation, and presence, i.e., the feeling to be present in the VE. Results revealed a high validity for the CAVE and VE in provoking height related self-reported fear and avoidance behavior in accordance with a trait measure of acrophobic fear. Increasing immersion significantly increased fear responses in high height anxious (HHA) participants, but did not affect presence. Nevertheless, presence was found to be an important predictor of fear responses. We conclude that a CAVE system can be used to elicit valid fear responses, which might be further enhanced by immersion manipulations independent from presence. These results may help to improve VRET efficacy and its transfer to real situations.},
  language  = {en}
}