@article{VenturaBortWirknerGenheimeretal.2018,
  author    = {Ventura-Bort, Carlos and Wirkner, Janine and Genheimer, Hannah and Wendt, Julia and Hamm, Alfons O. and Weymar, Mathias},
  title     = {Effects of Transcutaneous Vagus Nerve Stimulation (tVNS) on the P300 and Alpha-Amylase Level},
  series = {Frontiers in Human Neuroscience},
  volume    = {12},
  journal   = {Frontiers in Human Neuroscience},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2018.00202},
  pages     = {1 -- 12},
  year      = {2018},
  abstract  = {Recent research suggests that the P3b may be closely related to the activation of the locus coeruleus-norepinephrine (LC-NE) system. To further study the potential association, we applied a novel technique, the non-invasive transcutaneous vagus nerve stimulation (tVNS), which is speculated to increase noradrenaline levels. Using a within-subject cross-over design, 20 healthy participants received continuous tVNS and sham stimulation on two consecutive days (stimulation counterbalanced across participants) while performing a visual oddball task. During stimulation, oval non-targets (standard), normal-head (easy) and rotated-head (difficult) targets, as well as novel stimuli (scenes) were presented. As an indirect marker of noradrenergic activation we also collected salivary alpha-amylase (sAA) before and after stimulation. Results showed larger P3b amplitudes for target, relative to standard stimuli, irrespective of stimulation condition. Exploratory post hoc analyses, however, revealed that, in comparison to standard stimuli, easy (but not difficult) targets produced larger P3b (but not P3a) amplitudes during active tVNS, compared to sham stimulation. For sAA levels, although main analyses did not show differential effects of stimulation, direct testing revealed that tVNS (but not sham stimulation) increased sAA levels after stimulation. Additionally, larger differences between tVNS and sham stimulation in P3b magnitudes for easy targets were associated with larger increase in sAA levels after tVNS, but not after sham stimulation. Despite preliminary evidence for a modulatory influence of tVNS on the P3b, which may be partly mediated by activation of the noradrenergic system, additional research in this field is clearly warranted. Future studies need to clarify whether tVNS also facilitates other processes, such as learning and memory, and whether tVNS can be used as therapeutic tool.},
  language  = {en}
}
@article{GiraudierVenturaBortWeymar2020,
  author    = {Giraudier, Manon and Ventura-Bort, Carlos and Weymar, Mathias},
  title     = {Effects of transcutaneous vagus nerve stimulation (TVNS) on emotional word processing and recognition memory},
  series = {Psychophysiology},
  volume    = {57},
  journal   = {Psychophysiology},
  publisher = {Wiley-Blackwell},
  address   = {Malden},
  issn      = {0048-5772},
  pages     = {S73 -- S73},
  year      = {2020},
  language  = {en}
}
@misc{WeymarVenturaBortWirkneretal.2019,
  author    = {Weymar, Mathias and Ventura-Bort, Carlos and Wirkner, Janine and Genheimer, Hannah and Wendt, Julia and Hamm, Alfons O.},
  title     = {Effects of Transcutaneous Vagus Vagus Nerve Stimulation (TVNS) on selective attentions and emotional episodic memory : findings from ERP research},
  series = {Psychophysiology : journal of the Society for Psychophysiological Research},
  volume    = {56},
  journal   = {Psychophysiology : journal of the Society for Psychophysiological Research},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0048-5772},
  doi       = {10.1111/psyp.13501},
  pages     = {S12 -- S12},
  year      = {2019},
  abstract  = {Recent research indicates that non- invasive stimulation of the afferent auricular vagal nerve (tVNS) may modulate various cognitive and affec-tive functions, likely via activation of the locus coeruleus- norepinephrine (LC- NE) system. In a series of ERP studies we found that the attention- related P300 component is enhanced during continuous vagal stimula-tion, compared to sham, which is also related to increased salivary alpha amylase levels (a putative indirect marker for central NE activation). In another study, we investigated the effect of continuous tVNS on the late positive potential (LPP), an electrophysiological index for motivated atten-tion toward emotionally evocative cues, and the effects of tVNS on later recognition memory (1- week delay). Here, vagal stimulation prompted earlier LPP differences (300- 500 ms) between unpleasant and neutral scenes. During retrieval, vagal stimulation significantly improved memory performance for unpleasant, but not neutral pictures, compared to sham stimulation, which was also related to enhanced salivary alpha amylase levels. In line, unpleasant images encoded under tVNS compared to sham stimulation also produced enhanced ERP old/new differences (500- 800 ms) during retrieval indicating better recollection. Taken together, our studies suggest that tVNS facilitates attention, learning and episodic memory, likely via afferent projections to the arousal- modulated LC- NE system. We will, however, also show data that point to critical stimulation parameters (likely duration and frequency) that need to be considered when applying tVNS},
  language  = {en}
}
@inproceedings{VenturaBortSchneiderWeymar2021,
  author    = {Ventura-Bort, Carlos and Schneider, Paula and Weymar, Mathias},
  title     = {Effects of transcutaneous auricular vagus nerve stimulation (TAVNS) on interoception},
  series = {Psychophysiology : journal of the Society for Psychophysiological Research},
  volume    = {58},
  booktitle = {Psychophysiology : journal of the Society for Psychophysiological Research},
  publisher = {Wiley-Blackwell},
  address   = {Malden, Mass. [u.a.]},
  issn      = {1469-8986},
  doi       = {10.1111/psyp.13928},
  pages     = {S58 -- S58},
  year      = {2021},
  language  = {en}
}
@article{KoenigAblerAgartzetal.2020,
  author    = {Koenig, Julian and Abler, Birgit and Agartz, Ingrid and akerstedt, Torbjorn and Andreassen, Ole A. and Anthony, Mia and Baer, Karl-Juergen and Bertsch, Katja and Brown, Rebecca C. and Brunner, Romuald and Carnevali, Luca and Critchley, Hugo D. and Cullen, Kathryn R. and de Geus, Eco J. C. and de la Cruz, Feliberto and Dziobek, Isabel and Ferger, Marc D. and Fischer, Hakan and Flor, Herta and Gaebler, Michael and Gianaros, Peter J. and Giummarra, Melita J. and Greening, Steven G. and Guendelman, Simon and Heathers, James A. J. and Herpertz, Sabine C. and Hu, Mandy X. and Jentschke, Sebastian and Kaess, Michael and Kaufmann, Tobias and Klimes-Dougan, Bonnie and Koelsch, Stefan and Krauch, Marlene and Kumral, Deniz and Lamers, Femke and Lee, Tae-Ho and Lekander, Mats and Lin, Feng and Lotze, Martin and Makovac, Elena and Mancini, Matteo and Mancke, Falk and Mansson, Kristoffer N. T. and Manuck, Stephen B. and Mather, Mara and Meeten, Frances and Min, Jungwon and Mueller, Bryon and Muench, Vera and Nees, Frauke and Nga, Lin and Nilsonne, Gustav and Ordonez Acuna, Daniela and Osnes, Berge and Ottaviani, Cristina and Penninx, Brenda W. J. H. and Ponzio, Allison and Poudel, Govinda R. and Reinelt, Janis and Ren, Ping and Sakaki, Michiko and Schumann, Andy and Sorensen, Lin and Specht, Karsten and Straub, Joana and Tamm, Sandra and Thai, Michelle and Thayer, Julian F. and Ubani, Benjamin and van Der Mee, Denise J. and van Velzen, Laura S. and Ventura-Bort, Carlos and Villringer, Arno and Watson, David R. and Wei, Luqing and Wendt, Julia and Schreiner, Melinda Westlund and Westlye, Lars T. and Weymar, Mathias and Winkelmann, Tobias and Wu, Guo-Rong and Yoo, Hyun Joo and Quintana, Daniel S.},
  title     = {Cortical thickness and resting-state cardiac function across the lifespan},
  series = {Psychophysiology : journal of the Society for Psychophysiological Research},
  volume    = {58},
  journal   = {Psychophysiology : journal of the Society for Psychophysiological Research},
  number    = {7},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0048-5772},
  doi       = {10.1111/psyp.13688},
  pages     = {16},
  year      = {2020},
  abstract  = {Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting-state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega-analysis (N = 1,218 (50.5\% female), mean age 36.7 years (range: 12-87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS-or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between CT and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research.},
  language  = {en}
}
@article{WirknerVenturaBortSchwabeetal.2019,
  author    = {Wirkner, Janine and Ventura-Bort, Carlos and Schwabe, Lars and Hamm, Alfons O. and Weymar, Mathias},
  title     = {Chronic stress and emotion: Differential effects on attentional processing and recognition memory},
  series = {Psychoneuroendocrinology},
  volume    = {107},
  journal   = {Psychoneuroendocrinology},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0306-4530},
  doi       = {10.1016/j.psyneuen.2019.05.008},
  pages     = {93 -- 97},
  year      = {2019},
  abstract  = {Previous research indicates that acute stress around the time of learning facilitates attention and memory for emotionally salient information. Despite accumulating evidence for these acute stress effects, less is known about the role of chronic stress. In the present study, we therefore tested emotional and neutral scene processing and later recognition memory in female participants using hair cortisol concentrations as a biological marker for chronic stress. Event-related potentials recorded during picture viewing indicated enhanced late positive potentials (LPPs) for emotional, relative to neutral contents. These brain potentials varied as a function of long-term hair cortisol levels: hair-cortisol levels were positively related to overall LPP amplitudes. Results from recognition memory testing one week after encoding revealed better memory for emotional relative to neutral scenes. Hair-cortisol levels, however, were related to poorer memory accuracy. Taken together, our results indicate that chronic stress enhanced attentional processing during encoding of new stimuli and impaired later recognition memory. Results are discussed with regard to putatively opposite effects of chronic stress on certain brain regions (e.g., amygdala and hippocampus).},
  language  = {en}
}
@misc{WeymarVenturaBortWendtetal.2019,
  author    = {Weymar, Mathias and Ventura-Bort, Carlos and Wendt, Julia and Lischke, Alexander},
  title     = {Behavioral and neural evidence of enhanced long-term memory for untrustworthy faces},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {594},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-44292},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-442925},
  pages     = {10},
  year      = {2019},
  abstract  = {In daily life, we automatically form impressions of other individuals on basis of subtle facial features that convey trustworthiness. Because these face-based judgements influence current and future social interactions, we investigated how perceived trustworthiness of faces affects long-term memory using event-related potentials (ERPs). In the current study, participants incidentally viewed 60 neutral faces differing in trustworthiness, and one week later, performed a surprise recognition memory task, in which the same old faces were presented intermixed with novel ones. We found that after one week untrustworthy faces were better recognized than trustworthy faces and that untrustworthy faces prompted early (350-550 ms) enhanced frontal ERP old/new differences (larger positivity for correctly remembered old faces, compared to novel ones) during recognition. Our findings point toward an enhanced long-lasting, likely familiarity-based, memory for untrustworthy faces. Even when trust judgments about a person do not necessarily need to be accurate, a fast access to memories predicting potential harm may be important to guide social behaviour in daily life.},
  language  = {en}
}
@article{WeymarVenturaBortWendtetal.2019,
  author    = {Weymar, Mathias and Ventura-Bort, Carlos and Wendt, Julia and Lischke, Alexander},
  title     = {Behavioral and neural evidence of enhanced long-term memory for untrustworthy faces},
  series = {Scientific Reports},
  volume    = {9},
  journal   = {Scientific Reports},
  publisher = {Macmillan Publishers Limited},
  address   = {London},
  issn      = {2045-2322},
  doi       = {10.1038/s41598-019-55705-7},
  pages     = {8},
  year      = {2019},
  abstract  = {In daily life, we automatically form impressions of other individuals on basis of subtle facial features that convey trustworthiness. Because these face-based judgements influence current and future social interactions, we investigated how perceived trustworthiness of faces affects long-term memory using event-related potentials (ERPs). In the current study, participants incidentally viewed 60 neutral faces differing in trustworthiness, and one week later, performed a surprise recognition memory task, in which the same old faces were presented intermixed with novel ones. We found that after one week untrustworthy faces were better recognized than trustworthy faces and that untrustworthy faces prompted early (350-550 ms) enhanced frontal ERP old/new differences (larger positivity for correctly remembered old faces, compared to novel ones) during recognition. Our findings point toward an enhanced long-lasting, likely familiarity-based, memory for untrustworthy faces. Even when trust judgments about a person do not necessarily need to be accurate, a fast access to memories predicting potential harm may be important to guide social behaviour in daily life.},
  language  = {en}
}
@inproceedings{GiraudierVenturaBortWeymar2021,
  author    = {Giraudier, Manon and Ventura-Bort, Carlos and Weymar, Mathias},
  title     = {A pooled preliminary analysis on the effects of transcutaneous auricular vagus nerve stimulation on salivary alpha-amylase as noradrenergic biomarker},
  series = {Psychophysiology : journal of the Society for Psychophysiological Research},
  volume    = {58},
  booktitle = {Psychophysiology : journal of the Society for Psychophysiological Research},
  publisher = {Wiley-Blackwell},
  address   = {Malden, Mass. [u.a.]},
  issn      = {1469-8986},
  pages     = {S60 -- S60},
  year      = {2021},
  language  = {en}
}