@article{SchieleZieglerKollertetal.2018,
  author    = {Schiele, Miriam A. and Ziegler, Christiane and Kollert, Leonie and Katzorke, Andrea and Schartner, Christoph and Busch, Yasmin and Gromer, Daniel and Reif, Andreas and Pauli, Paul and Deckert, J{\"u}rgen and Herrmann, Martin J. and Domschke, Katharina},
  title     = {Plasticity of Functional MAOA Gene Methylation in Acrophobia},
  series = {International Journal of Neuropsychopharmacology},
  volume    = {21},
  journal   = {International Journal of Neuropsychopharmacology},
  number    = {9},
  doi       = {10.1093/ijnp/pyy050},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-228571},
  pages     = {822-827},
  year      = {2018},
  abstract  = {Epigenetic mechanisms have been proposed to mediate fear extinction in animal models. Here, MAOA methylation was analyzed via direct sequencing of sodium bisulfite-treated DNA extracted from blood cells before and after a 2-week exposure therapy in a sample of n = 28 female patients with acrophobia as well as in n = 28 matched healthy female controls. Clinical response was measured using the Acrophobia Questionnaire and the Attitude Towards Heights Questionnaire. The functional relevance of altered MAOA methylation was investigated by luciferase-based reporter gene assays. MAOA methylation was found to be significantly decreased in patients with acrophobia compared with healthy controls. Furthermore, MAOA methylation levels were shown to significantly increase after treatment and correlate with treatment response as reflected by decreasing Acrophobia Questionnaire/Attitude Towards Heights Questionnaire scores. Functional analyses revealed decreased reporter gene activity in presence of methylated compared with unmethylated pCpGfree_MAOA reporter gene vector constructs. The present proof-of-concept psychotherapy-epigenetic study for the first time suggests functional MAOA methylation changes as a potential epigenetic correlate of treatment response in acrophobia and fosters further investigation into the notion of epigenetic mechanisms underlying fear extinction.},
  language  = {en}
}
@article{RosenbaumBlumSchweizeretal.2018,
  author    = {Rosenbaum, David and Blum, Leonore and Schweizer, Paul and Fallgatter, Andreas J. and Herrmann, Martin J. and Ehlis, Ann-Christine and Metzger, Florian G.},
  title     = {Comparison of speed versus complexity effects on the hemodynamic response of the trail making test in block designs},
  series = {Neurophotonics},
  volume    = {5},
  journal   = {Neurophotonics},
  number    = {4},
  doi       = {10.1117/1.NPh.5.4.045007},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226982},
  pages     = {045007, 1-9},
  year      = {2018},
  abstract  = {The use of functional near-infrared spectroscopy (fNIRS) in block designs provides measures of cortical activity in ecologically valid environments. However, in some cases, the use of block designs may be problematic when data are not corrected for performance in a time-restricted block. We sought to investigate the effects of task complexity and processing speed on hemodynamic responses in an fNIRS block design. To differentiate the effects of task complexity and processing speed, 20 subjects completed the trail making test (TMT) in two versions (TMT-A versus TMT-B) and three different speed levels (slow versus moderate versus fast). During TMT-A, subjects are asked to connect encircled numbers in numerically ascending order (1-2-3 ... ). In the more complex TMT-B, subjects are instructed to connect encircled numbers and letters in alternating ascending order (1-A-2-B ... ). To illustrate the obscuring effects of processing speed on task complexity, we perform two different analyses. First, we analyze the classical measures of oxygenated blood, and second, we analyze the measures corrected for the number of processed items. Our results show large effects for processing speed within the bilateral inferior frontal gyrus, left dorsolateral prefrontal cortex, and superior parietal lobule (SPL). The TMT contrast did not show significant effects with classical measures, although trends are observed for higher activation during TMT-B. When corrected for processed items, higher activity for TMT-B in comparison to TMT-A is found within the SPL. The results are discussed in light of recent research designs, and simple to use correction methods are suggested. (c) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.},
  language  = {en}
}
@article{DittertHuettnerPolaketal.2018,
  author    = {Dittert, Natalie and H{\"u}ttner, Sandrina and Polak, Thomas and Herrmann, Martin J.},
  title     = {Augmentation of fear extinction by transcranial direct current stimulation (tDCS)},
  series = {Frontiers in Behavioral Neuroscience},
  volume    = {12},
  journal   = {Frontiers in Behavioral Neuroscience},
  number    = {76},
  doi       = {10.3389/fnbeh.2018.00076},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176056},
  year      = {2018},
  abstract  = {Although posttraumatic stress disorder (PTSD; DSM-V 309.82) and anxiety disorders (DSM-V 300.xx) are widely spread mental disorders, the effectiveness of their therapy is still unsatisfying. Non-invasive brain-stimulation techniques like transcranial direct current stimulation (tDCS) might be an option to improve extinction learning, which is a main functional factor of exposure-based therapy for anxiety disorders. To examine this hypothesis, we used a fear conditioning paradigm with female faces as conditioned stimuli (CS) and a 95-dB female scream as unconditioned stimulus (UCS). We aimed to perform a tDCS of the ventromedial prefrontal cortex (vmPFC), which is mainly involved in the control of extinction-processes. Therefore, we applied two 4 × 4 cm electrodes approximately at the EEG-positions F7 and F8 and used a direct current of 1.5 mA. The 20-min stimulation was started during a 10-min break between acquisition and extinction and went on overall extinction-trials. The healthy participants were randomly assigned in two double-blinded process into two sham stimulation and two verum stimulation groups with opposite current flow directions. To measure the fear reactions, we used skin conductance responses (SCR) and subjective ratings. We performed a generalized estimating equations model for the SCR to assess the impact of tDCS and current flow direction on extinction processes for all subjects that showed a successful conditioning (N = 84). The results indicate that tDCS accelerates early extinction processes with a significantly faster loss of CS+/CS- discrimination. The discrimination loss was driven by a significant decrease in reaction toward the CS+ as well as an increase in reaction toward the CS- in the tDCS verum groups, whereas the sham groups showed no significant reaction changes during this period. Therefore, we assume that tDCS of the vmPFC can be used to enhance early extinction processes successfully. But before it should be tested in a clinical context further investigation is needed to assess the reason for the reaction increase on CS-. If this negative side effect can be avoided, tDCS may be a tool to improve exposure-based anxiety therapies.},
  language  = {en}
}