@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} } @article{FarmerStrzelczykFinisguerraetal.2021, author = {Farmer, Adam D. and Strzelczyk, Adam and Finisguerra, Alessandra and Gourine, Alexander V. and Gharabaghi, Alireza and Hasan, Alkomiet and Burger, Andreas M. and Jaramillo, Andr{\´e}s M. and Mertens, Ann and Majid, Arshad and Verkuil, Bart and Badran, Bashar W. and Ventura-Bort, Carlos and Gaul, Charly and Beste, Christian and Warren, Christopher M. and Quintana, Daniel S. and H{\"a}mmerer, Dorothea and Freri, Elena and Frangos, Eleni and Tobaldini, Eleonora and Kaniusas, Eugenijus and Rosenow, Felix and Capone, Fioravante and Panetsos, Fivos and Ackland, Gareth L. and Kaithwas, Gaurav and O'Leary, Georgia H. and Genheimer, Hannah and Jacobs, Heidi I. L. and Van Diest, Ilse and Schoenen, Jean and Redgrave, Jessica and Fang, Jiliang and Deuchars, Jim and Sz{\´e}les, Jozsef C. and Thayer, Julian F. and More, Kaushik and Vonck, Kristl and Steenbergen, Laura and Vianna, Lauro C. and McTeague, Lisa M. and Ludwig, Mareike and Veldhuizen, Maria G. and De Couck, Marijke and Casazza, Marina and Keute, Marius and Bikson, Marom and Andreatta, Marta and D'Agostini, Martina and Weymar, Mathias and Betts, Matthew and Prigge, Matthias and Kaess, Michael and Roden, Michael and Thai, Michelle and Schuster, Nathaniel M. and Montano, Nicola and Hansen, Niels and Kroemer, Nils B. and Rong, Peijing and Fischer, Rico and Howland, Robert H. and Sclocco, Roberta and Sellaro, Roberta and Garcia, Ronald G. and Bauer, Sebastian and Gancheva, Sofiya and Stavrakis, Stavros and Kampusch, Stefan and Deuchars, Susan A. and Wehner, Sven and Laborde, Sylvain and Usichenko, Taras and Polak, Thomas and Zaehle, Tino and Borges, Uirassu and Teckentrup, Vanessa and Jandackova, Vera K. and Napadow, Vitaly and Koenig, Julian}, title = {International Consensus Based Review and Recommendations for Minimum Reporting Standards in Research on Transcutaneous Vagus Nerve Stimulation (Version 2020)}, series = {Frontiers in Human Neuroscience}, volume = {14}, journal = {Frontiers in Human Neuroscience}, issn = {1662-5161}, doi = {10.3389/fnhum.2020.568051}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234346}, year = {2021}, abstract = {Given its non-invasive nature, there is increasing interest in the use of transcutaneous vagus nerve stimulation (tVNS) across basic, translational and clinical research. Contemporaneously, tVNS can be achieved by stimulating either the auricular branch or the cervical bundle of the vagus nerve, referred to as transcutaneous auricular vagus nerve stimulation(VNS) and transcutaneous cervical VNS, respectively. In order to advance the field in a systematic manner, studies using these technologies need to adequately report sufficient methodological detail to enable comparison of results between studies, replication of studies, as well as enhancing study participant safety. We systematically reviewed the existing tVNS literature to evaluate current reporting practices. Based on this review, and consensus among participating authors, we propose a set of minimal reporting items to guide future tVNS studies. The suggested items address specific technical aspects of the device and stimulation parameters. We also cover general recommendations including inclusion and exclusion criteria for participants, outcome parameters and the detailed reporting of side effects. Furthermore, we review strategies used to identify the optimal stimulation parameters for a given research setting and summarize ongoing developments in animal research with potential implications for the application of tVNS in humans. Finally, we discuss the potential of tVNS in future research as well as the associated challenges across several disciplines in research and clinical practice.}, language = {en} } @article{GuhnDreslerAndreattaetal.2014, author = {Guhn, Anne and Dresler, Thomas and Andreatta, Marta and M{\"u}ller, Laura D. and Hahn, Tim and Tupak, Sara V. and Polak, Thomas and Deckert, J{\"u}rgen and Herrmann, Martin J.}, title = {Medial prefrontal cortex stimulation modulates the processing of conditioned fear}, doi = {10.3389/fnbeh.2014.00044}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111309}, year = {2014}, abstract = {The extinction of conditioned fear depends on an efficient interplay between the amygdala and the medial prefrontal cortex (mPFC). In rats, high-frequency electrical mPFC stimulation has been shown to improve extinction by means of a reduction of amygdala activity. However, so far it is unclear whether stimulation of homologues regions in humans might have similar beneficial effects. Healthy volunteers received one session of either active or sham repetitive transcranial magnetic stimulation (rTMS) covering the mPFC while undergoing a 2-day fear conditioning and extinction paradigm. Repetitive TMS was applied offline after fear acquisition in which one of two faces (CS+ but not CS-) was associated with an aversive scream (UCS). Immediate extinction learning (day 1) and extinction recall (day 2) were conducted without UCS delivery. Conditioned responses (CR) were assessed in a multimodal approach using fear-potentiated startle (FPS), skin conductance responses (SCR), functional near-infrared spectroscopy (fNIRS), and self-report scales. Consistent with the hypothesis of a modulated processing of conditioned fear after high-frequency rTMS, the active group showed a reduced CS+/CS- discrimination during extinction learning as evident in FPS as well as in SCR and arousal ratings. FPS responses to CS+ further showed a linear decrement throughout both extinction sessions. This study describes the first experimental approach of influencing conditioned fear by using rTMS and can thus be a basis for future studies investigating a complementation of mPFC stimulation to cognitive behavioral therapy (CBT).}, language = {en} } @article{HaberstumpfForsterLeinweberetal.2022, author = {Haberstumpf, Sophia and Forster, Andr{\´e} and Leinweber, Jonas and Rauskolb, Stefanie and Hewig, Johannes and Sendtner, Michael and Lauer, Martin and Polak, Thomas and Deckert, J{\"u}rgen and Herrmann, Martin J.}, title = {Measurement invariance testing of longitudinal neuropsychiatric test scores distinguishes pathological from normative cognitive decline and highlights its potential in early detection research}, series = {Journal of Neuropsychology}, volume = {16}, journal = {Journal of Neuropsychology}, number = {2}, doi = {10.1111/jnp.12269}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318932}, pages = {324 -- 352}, year = {2022}, abstract = {Objective Alzheimer's disease (AD) is a growing challenge worldwide, which is why the search for early-onset predictors must be focused as soon as possible. Longitudinal studies that investigate courses of neuropsychological and other variables screen for such predictors correlated to mild cognitive impairment (MCI). However, one often neglected issue in analyses of such studies is measurement invariance (MI), which is often assumed but not tested for. This study uses the absence of MI (non-MI) and latent factor scores instead of composite variables to assess properties of cognitive domains, compensation mechanisms, and their predictability to establish a method for a more comprehensive understanding of pathological cognitive decline. Methods An exploratory factor analysis (EFA) and a set of increasingly restricted confirmatory factor analyses (CFAs) were conducted to find latent factors, compared them with the composite approach, and to test for longitudinal (partial-)MI in a neuropsychiatric test battery, consisting of 14 test variables. A total of 330 elderly (mean age: 73.78 ± 1.52 years at baseline) were analyzed two times (3 years apart). Results EFA revealed a four-factor model representing declarative memory, attention, working memory, and visual-spatial processing. Based on CFA, an accurate model was estimated across both measurement timepoints. Partial non-MI was found for parameters such as loadings, test- and latent factor intercepts as well as latent factor variances. The latent factor approach was preferable to the composite approach. Conclusion The overall assessment of non-MI latent factors may pose a possible target for this field of research. Hence, the non-MI of variances indicated variables that are especially suited for the prediction of pathological cognitive decline, while non-MI of intercepts indicated general aging-related decline. As a result, the sole assessment of MI may help distinguish pathological from normative aging processes and additionally may reveal compensatory neuropsychological mechanisms.}, language = {en} } @article{HaberstumpfLeinweberLaueretal.2022, author = {Haberstumpf, Sophia and Leinweber, Jonas and Lauer, Martin and Polak, Thomas and Deckert, J{\"u}rgen and Herrmann, Martin J.}, title = {Factors associated with dropout in the longitudinal Vogel study of cognitive decline}, series = {The European Journal of Neuroscience}, volume = {56}, journal = {The European Journal of Neuroscience}, number = {9}, doi = {10.1111/ejn.15446}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318945}, pages = {5587 -- 5600}, year = {2022}, abstract = {Dementia, including Alzheimer's disease, is a growing problem worldwide. Prevention or early detection of the disease or a prodromal cognitive decline is necessary. By means of our long-term follow-up 'Vogel study', we aim to predict the pathological cognitive decline of a German cohort (mean age was 73.9 ± 1.55 years at first visit) with three measurement time points within 6 years per participant. Especially in samples of the elderly and subjects with chronic or co-morbid diseases, dropouts are one of the biggest problems of long-term studies. In contrast to the large number of research articles conducted on the course of dementia, little research has been done on the completion of treatment. To ensure unbiased and reliable predictors of cognitive decline from study completers, our objective was to determine predictors of dropout. We conducted multivariate analyses of covariance and multinomial logistic regression analyses to compare and predict the subject's dropout behaviour at the second visit 3 years after baseline (full participation, partial participation and no participation/dropout) with neuropsychiatric, cognitive, blood and lifestyle variables. Lower performance in declarative memory, attention and visual-spatial processing predicted dropout rather than full participation. Lower performance in visual-spatial processing predicted partial participation as opposed to full participation. Furthermore, lower performance in mini-mental status examination predicted whether subjects dropped out or participated partially instead of full participation. Baseline cognitive parameters are associated with dropouts at follow-up with a loss of impaired participants. We expect a bias into a healthier sample over time.}, language = {en} } @article{HerrmannBeierSimonsetal.2016, author = {Herrmann, Martin J. and Beier, Jennifer S. and Simons, Bibiane and Polak, Thomas}, title = {Transcranial Direct Current Stimulation (tDCS) of the Right Inferior Frontal Gyrus Attenuates Skin Conductance Responses to Unpredictable Threat Conditions}, series = {Frontiers in Human Neuroscience}, volume = {10}, journal = {Frontiers in Human Neuroscience}, number = {352}, doi = {10.3389/fnhum.2016.00352}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146486}, year = {2016}, abstract = {Patients with panic and post-traumatic stress disorders seem to show increased psychophysiological reactions to conditions of unpredictable (U) threat, which has been discussed as a neurobiological marker of elevated levels of sustained fear in these disorders. Interestingly, a recent study found that the right inferior frontal gyrus (rIFG) is correlated to the successful regulation of sustained fear during U threat. Therefore this study aimed to examine the potential use of non-invasive brain stimulation to foster the rIFG by means of anodal transcranial direct current stimulation (tDCS) in order to reduce psychophysiological reactions to U threat. Twenty six participants were randomly assigned into an anodal and sham stimulation group in a double-blinded manner. Anodal and cathodal electrodes (7 * 5 cm) were positioned right frontal to target the rIFG. Stimulation intensity was I = 2 mA applied for 20 min during a task including U threat conditions (NPU-task). The effects of the NPU paradigm were measured by assessing the emotional startle modulation and the skin conductance response (SCR) at the outset of the different conditions. We found a significant interaction effect of condition × tDCS for the SCR (F(2,48) = 6.3, p < 0.01) without main effects of condition and tDCS. Post hoc tests revealed that the increase in SCR from neutral (N) to U condition was significantly reduced in verum compared to the sham tDCS group (t(24) = 3.84, p < 0.001). Our results emphasize the causal role of rIFG for emotional regulation and the potential use of tDCS to reduce apprehension during U threat conditions and therefore as a treatment for anxiety disorders.}, language = {en} } @article{KatzorkeZellerMuelleretal.2017, author = {Katzorke, Andrea and Zeller, Julia B. M. and M{\"u}ller, Laura D. and Lauer, Martin and Polak, Thomas and Reif, Andreas and Deckert, J{\"u}rgen and Herrmann, Martin J.}, title = {Reduced activity in the right inferior frontal gyrus in elderly APOE-E4 carriers during a verbal fluency task}, series = {Frontiers in Human Neuroscience}, volume = {11}, journal = {Frontiers in Human Neuroscience}, doi = {10.3389/fnhum.2017.00046}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171892}, year = {2017}, abstract = {Apolipoprotein-E4 (APOE-E4) is a major genetic risk factor for developing Alzheimer's disease (AD). The verbal fluency task (VFT), especially the subtask category fluency, has shown to provide a good discrimination between cognitively normal controls and subjects with AD. Interestingly, APOE-E4 seems to have no effect on the behavioral performance during a VFT in healthy elderly. Thus, the purpose of the present study was to reveal possible compensation mechanisms by investigating the effect of APOE-E4 on the hemodynamic response in non-demented elderly during a VFT by using functional near-infrared spectroscopy (fNIRS). We compared performance and hemodynamic response of high risk APOE-E4/E4, -E3/E4 carriers with neutral APOE-E3/E3 non-demented subjects (N = 288; 70-77 years). No difference in performance was found. APOE-E4/E4, -E3/E4 carriers had a decreased hemodynamic response in the right inferior frontal junction (IFJ) with a corresponding higher response in the left middle frontal gyrus (MFG) during category fluency. Performance was correlated with the hemodynamic response in the MFG. We assume a compensation of decreased IFJ brain activation by utilizing the MFG during category fluency and thus resulting in no behavioral differences between APOE-groups during the performance of a VFT.}, language = {en} } @article{LauererTiedemannPolaketal.2021, author = {Lauerer, Elias and Tiedemann, Elena and Polak, Thomas and Simmenroth, Anne}, title = {Can smoking cessation be taught online? A prospective study comparing e-learning and role-playing in medical education}, series = {International Journal of Medical Education}, volume = {12}, journal = {International Journal of Medical Education}, doi = {10.5116/ijme.5ff9.bccc}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230056}, pages = {12-21}, year = {2021}, abstract = {Objectives: We compared the effect of different didactic formats - e - learning and role-playing - on medical students' knowledge and counselling skills in smoking cessation training. Methods: At a German medical school, 145 third-year students were randomly allocated to attend an online course with video examples or an attendance course with role-playing. Students were trained in smoking cessation counselling according to the 5A's (ask, advise, assess, assist, arrange) for approximately 90 minutes. Practical skills were measured in an objective structured clinical examination (OSCE) and represent the primary endpoint of this prospective comparative study. Additionally, changes in theoretic knowledge were assessed by pre - and post - interventional questionnaires and a final written exam. Results: In the OSCE, overall scores were higher in the attendance group (Mdn=70.8 \% vs. 62.8 \%; U=119; p=.087, n=36), but a statistical advantage was only found in one single counselling sequence ("Assist": Mdn=66.7 \% vs. 51.4 \%; p = .049) and the rating of the standardised patients (M=4.7 vs. 4.2 out of 5 points, t(27.836)=2.0, p=.028). Students' results (n=130) from self-assessment and written exams suggest that both approaches are equally well suited to increase theoretical knowledge. The online course was more time efficient (90 vs. 73 minutes). Conclusions: Seminar and web-based training seem equally well suited for transferring knowledge and skills on tobacco cessation counselling. Considering their particular strengths, these two teaching approaches could be combined.}, language = {en} } @article{ManishNueckelMuehlbergeretal.2013, author = {Manish, Asthana and Nueckel, Katharina and M{\"u}hlberger, Andreas and Neueder, Dorothea and Polak, Thomas and Domschke, Katharina and Deckert, J{\"u}rgen and Herrmann, Martin J.}, title = {Effects of transcranial direct current stimulation on consolidation of fear memory}, series = {Frontiers in Neuropsychiatric Imaging and Stimulation}, journal = {Frontiers in Neuropsychiatric Imaging and Stimulation}, doi = {10.3389/fpsyt.2013.00107}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97294}, year = {2013}, abstract = {It has been shown that applying transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (DLPFC) influences declarative memory processes. This study investigates the efficacy of tDCS on emotional memory consolidation, especially experimental fear conditioning. We applied an auditory fear-conditioning paradigm, in which two differently colored squares (blue and yellow) were presented as conditioned stimuli (CS) and an auditory stimulus as unconditioned stimulus (UCS). Sixty-nine participants were randomly assigned into three groups: anodal, cathodal, and sham stimulation. The participants of the two active groups (i.e., anodal and cathodal) received tDCS over the left DLPFC for 12 min after fear conditioning. The effect of fear conditioning and consolidation (24 h later) was measured by assessing the skin conductance response (SCR) to the CS. The results provide evidence that cathodal stimulation of the left DLPFC leads to an inhibitory effect on fear memory consolidation compared to anodal and sham stimulation, as indicated by decreased SCRs to CS+ presentation during extinction training at day 2. In conclusion, current work suggests that cathodal stimulation interferes with processes of fear memory consolidation.}, language = {en} } @article{ReimannStopperPolaketal.2020, author = {Reimann, Hauke and Stopper, Helga and Polak, Thomas and Lauer, Martin and Herrmann, Martin J. and Deckert, J{\"u}rgen and Hintzsche, Henning}, title = {Micronucleus frequency in buccal mucosa cells of patients with neurodegenerative diseases}, series = {Scientific Reports}, volume = {10}, journal = {Scientific Reports}, doi = {10.1038/s41598-020-78832-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231430}, year = {2020}, abstract = {Neurodegenerative diseases show an increase in prevalence and incidence, with the most prominent example being Alzheimer's disease. DNA damage has been suggested to play a role in the pathogenesis, but the exact mechanisms remain elusive. We enrolled 425 participants with and without neurodegenerative diseases and analyzed DNA damage in the form of micronuclei in buccal mucosa samples. In addition, other parameters such as binucleated cells, karyolytic cells, and karyorrhectic cells were quantified. No relevant differences in DNA damage and cytotoxicity markers were observed in patients compared to healthy participants. Furthermore, other parameters such as lifestyle factors and diseases were also investigated. Overall, this study could not identify a direct link between changes in buccal cells and neurogenerative diseases, but highlights the influence of lifestyle factors and diseases on the human buccal cytome.}, language = {en} }