@article{NettelsMuellerSpaethKuesteretal.2009, author = {Nettels, Daniel and M{\"u}ller-Sp{\"a}th, Sonja and K{\"u}ster, Frank and Hofmann, Hagen and Haenni, Domminik and R{\"u}egger, Stefan and Reymond, Luc and Hoffmann, Armin S. and Kubelka, Jan and Heinz, Benjamin and Gast, Klaus and Best, Robert B. and Schuler, Benjamin}, title = {Single-molecule spectroscopy of the temperature-induced collapse of unfolded proteins}, issn = {0027-8424}, year = {2009}, abstract = {We used single-molecule FRET in combination with other biophysical methods and molecular simulations to investigate the effect of temperature on the dimensions of unfolded proteins. With singlemolecule FRET, this question can be addressed even under nearnative conditions, where most molecules are folded, allowing us to probe a wide range of denaturant concentrations and temperatures. We find a compaction of the unfolded state of a small cold shock protein with increasing temperature in both the presence and the absence of denaturant, with good agreement between the results from single-molecule FRET and dynamic light scattering. Although dissociation of denaturant from the polypeptide chain with increasing temperature accounts for part of the compaction, the results indicate an important role for additional temperaturedependent interactions within the unfolded chain. The observation of a collapse of a similar extent in the extremely hydrophilic, intrinsically disordered protein prothymosin suggests that the hydrophobic effect is not the sole source of the underlying interactions. Circular dichroism spectroscopy and replica exchange molecular dynamics simulations in explicit water show changes in secondary structure content with increasing temperature and suggest a contribution of intramolecular hydrogen bonding to unfolded state collapse.}, language = {en} } @inproceedings{VoellerSalzwedelReibisetal.2014, author = {V{\"o}ller, Heinz and Salzwedel, Annett and Reibis, Rona Katharina and Kaminski, S. and Buhlert, Hermann and Eichler, Sarah and Wegscheider, Karl}, title = {Age and fitness level are strongest limitations of exercise capacity during inpatient cardiac rehabilitation}, series = {European heart journal}, volume = {35}, booktitle = {European heart journal}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0195-668X}, pages = {899 -- 899}, year = {2014}, language = {en} } @article{HeinzJungStegmann2012, author = {Heinz, S. and Jung, I. and Stegmann, Christian}, title = {Systematic studies of the Richardson-Lucy deconvolution algorithm applied to VHE gamma data}, series = {ASTROPARTICLE PHYSICS}, volume = {36}, journal = {ASTROPARTICLE PHYSICS}, number = {1}, publisher = {ELSEVIER SCIENCE BV}, address = {AMSTERDAM}, issn = {0927-6505}, doi = {10.1016/j.astropartphys.2012.05.013}, pages = {146 -- 150}, year = {2012}, abstract = {The Richardson-Lucy deconvolution algorithm was applied to astronomical images in the very high-energy regime with photon energies above 100 GeV. Through a systematic study with respect to source significance, background level and source morphology we were able to derive optimal deconvolution parameters. The results presented show that deconvolution makes it possible to study structural details well below the angular resolution of the very high-energy gamma-ray experiment. (C) 2012 Elsevier B.V. All rights reserved.}, language = {en} } @article{HansenDendaleConinxetal.2017, author = {Hansen, Dominique and Dendale, Paul and Coninx, Karin and Vanhees, Luc and Piepoli, Massimo F. and Niebauer, Josef and Cornelissen, Veronique and Pedretti, Roberto and Geurts, Eva and Ruiz, Gustavo R. and Corra, Ugo and Schmid, Jean-Paul and Greco, Eugenio and Davos, Constantinos H. and Edelmann, Frank and Abreu, Ana and Rauch, Bernhard and Ambrosetti, Marco and Braga, Simona S. and Barna, Olga and Beckers, Paul and Bussotti, Maurizio and Fagard, Robert and Faggiano, Pompilio and Garcia-Porrero, Esteban and Kouidi, Evangelia and Lamotte, Michel and Neunhaeuserer, Daniel and Reibis, Rona Katharina and Spruit, Martijn A. and Stettler, Christoph and Takken, Tim and Tonoli, Cajsa and Vigorito, Carlo and V{\"o}ller, Heinz and Doherty, Patrick}, title = {The European Association of Preventive Cardiology Exercise Prescription in Everyday Practice and Rehabilitative Training (EXPERT) tool: A digital training and decision support system for optimized exercise prescription in cardiovascular disease. Concept, definitions and construction methodology}, series = {European journal of preventive cardiology : the official ESC journal for primary \& secondary cardiovascular prevention, rehabilitation and sports cardiology}, volume = {24}, journal = {European journal of preventive cardiology : the official ESC journal for primary \& secondary cardiovascular prevention, rehabilitation and sports cardiology}, publisher = {Sage Publ.}, address = {London}, issn = {2047-4873}, doi = {10.1177/2047487317702042}, pages = {1017 -- 1031}, year = {2017}, abstract = {Background Exercise rehabilitation is highly recommended by current guidelines on prevention of cardiovascular disease, but its implementation is still poor. Many clinicians experience difficulties in prescribing exercise in the presence of different concomitant cardiovascular diseases and risk factors within the same patient. It was aimed to develop a digital training and decision support system for exercise prescription in cardiovascular disease patients in clinical practice: the European Association of Preventive Cardiology Exercise Prescription in Everyday Practice and Rehabilitative Training (EXPERT) tool. Methods EXPERT working group members were requested to define (a) diagnostic criteria for specific cardiovascular diseases, cardiovascular disease risk factors, and other chronic non-cardiovascular conditions, (b) primary goals of exercise intervention, (c) disease-specific prescription of exercise training (intensity, frequency, volume, type, session and programme duration), and (d) exercise training safety advices. The impact of exercise tolerance, common cardiovascular medications and adverse events during exercise testing were further taken into account for optimized exercise prescription. Results Exercise training recommendations and safety advices were formulated for 10 cardiovascular diseases, five cardiovascular disease risk factors (type 1 and 2 diabetes, obesity, hypertension, hypercholesterolaemia), and three common chronic non-cardiovascular conditions (lung and renal failure and sarcopaenia), but also accounted for baseline exercise tolerance, common cardiovascular medications and occurrence of adverse events during exercise testing. An algorithm, supported by an interactive tool, was constructed based on these data. This training and decision support system automatically provides an exercise prescription according to the variables provided. Conclusion This digital training and decision support system may contribute in overcoming barriers in exercise implementation in common cardiovascular diseases.}, language = {en} } @article{StrackeBayerZimmermannetal.1999, author = {Stracke, A. and Bayer, A. and Zimmermann, S. and Wendorff, Joachim Heinz and Wirges, Werner and Bauer-Gogonea, Simona and Bauer, Siegfried and Gerhard, Reimund}, title = {Relaxation behaviour of electrically induced polar orientation and of optically induced non-polar orientation in an azo-chromophore side group polymer}, issn = {0022-3727}, year = {1999}, language = {en} } @article{deVeraBoettgerdelaTorreNoetzeletal.2012, author = {de Vera, Jean-Pierre Paul and B{\"o}ttger, Ute and de la Torre N{\"o}tzel, Rosa and Sanchez, Francisco J. and Grunow, Dana and Schmitz, Nicole and Lange, Caroline and H{\"u}bers, Heinz-Wilhelm and Billi, Daniela and Baque, Mickael and Rettberg, Petra and Rabbow, Elke and Reitz, G{\"u}nther and Berger, Thomas and M{\"o}ller, Ralf and Bohmeier, Maria and Horneck, Gerda and Westall, Frances and J{\"a}nchen, Jochen and Fritz, J{\"o}rg and Meyer, Cornelia and Onofri, Silvano and Selbmann, Laura and Zucconi, Laura and Kozyrovska, Natalia and Leya, Thomas and Foing, Bernard and Demets, Rene and Cockell, Charles S. and Bryce, Casey and Wagner, Dirk and Serrano, Paloma and Edwards, Howell G. M. and Joshi, Jasmin Radha and Huwe, Bj{\"o}rn and Ehrenfreund, Pascale and Elsaesser, Andreas and Ott, Sieglinde and Meessen, Joachim and Feyh, Nina and Szewzyk, Ulrich and Jaumann, Ralf and Spohn, Tilman}, title = {Supporting Mars exploration BIOMEX in Low Earth Orbit and further astrobiological studies on the Moon using Raman and PanCam technology}, series = {Planetary and space science}, volume = {74}, journal = {Planetary and space science}, number = {1}, publisher = {Elsevier}, address = {Oxford}, issn = {0032-0633}, doi = {10.1016/j.pss.2012.06.010}, pages = {103 -- 110}, year = {2012}, abstract = {The Low Earth Orbit (LEO) experiment Biology and Mars Experiment (BIOMEX) is an interdisciplinary and international space research project selected by ESA. The experiment will be accommodated on the space exposure facility EXPOSE-R2 on the International Space Station (ISS) and is foreseen to be launched in 2013. The prime objective of BIOMEX is to measure to what extent biomolecules, such as pigments and cellular components, are resistant to and able to maintain their stability under space and Mars-like conditions. The results of BIOMEX will be relevant for space proven biosignature definition and for building a biosignature data base (e.g. the proposed creation of an international Raman library). The library will be highly relevant for future space missions such as the search for life on Mars. The secondary scientific objective is to analyze to what extent terrestrial extremophiles are able to survive in space and to determine which interactions between biological samples and selected minerals (including terrestrial, Moon- and Mars analogs) can be observed under space and Mars-like conditions. In this context, the Moon will be an additional platform for performing similar experiments with negligible magnetic shielding and higher solar and galactic irradiation compared to LEO. Using the Moon as an additional astrobiological exposure platform to complement ongoing astrobiological LEO investigations could thus enhance the chances of detecting organic traces of life on Mars. We present a lunar lander mission with two related objectives: a lunar lander equipped with Raman and PanCam instruments which can analyze the lunar surface and survey an astrobiological exposure platform. This dual use of testing mission technology together with geo- and astrobiological analyses will significantly increase the science return, and support the human preparation objectives. It will provide knowledge about the Moon's surface itself and, in addition, monitor the stability of life-markers, such as cells, cell components and pigments, in an extraterrestrial environment with much closer radiation properties to the surface of Mars. The combination of a Raman data base of these data together with data from LEO and space simulation experiments, will lead to further progress on the analysis and interpretation of data that we will obtain from future Moon and Mars exploration missions.}, language = {en} } @article{SianovaZenNothoferetal.2002, author = {Sianova, D. and Zen, Achmad and Nothofer, Heinz-Georg and Asawapirom, Udom and Scherf, Ullrich and Hagen, R. and Bieringer, Thomas and Kostromine, S. and Neher, Dieter}, title = {Photoaddressable alignment layers for fluorescent polymers in polarized electroluminescence devices}, year = {2002}, language = {en} } @article{OdaNothoferLieseretal.2000, author = {Oda, Masao and Nothofer, Heinz-Georg and Lieser, G. and Scherf, Ullrich and Meskers, S. C. J. and Neher, Dieter}, title = {Circularly-polarized electroluminescence from liquid-crystalline chiral polyfluorenes}, year = {2000}, language = {en} } @article{OdaMeskersNothoferetal.2000, author = {Oda, Masao and Meskers, S. C. J. and Nothofer, Heinz-Georg and Scherf, Ullrich and Neher, Dieter}, title = {Chiroptical properties of chiral-substituted polyfluorenes}, year = {2000}, language = {en} } @misc{KuschpelLiuSchadetal.2015, author = {Kuschpel, Maxim S. and Liu, Shuyan and Schad, Daniel and Heinzel, Stephan and Heinz, Andreas and Rapp, Michael A.}, title = {Differential effects of wakeful rest, music and video game playing on working memory performance in the n-back task}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-85151}, year = {2015}, abstract = {The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on working memory performance. Young adults were exposed to breaks involving (i) eyes-open resting, (ii) listening to music and (iii) playing the video game "Angry Birds" before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the "Angry Birds" video game during a short learning break led to a decline in task performance over the course of the task as compared to eyes-open resting and listening to music, although overall task performance was not impaired. This effect was associated with high levels of daily mind wandering and low self-reported ability to concentrate. These findings indicate that video games can negatively affect working memory performance over time when played in between learning tasks. We suggest further investigation of these effects because of their relevance to everyday activity.}, language = {en} } @misc{LiuSchadKuschpeletal.2016, author = {Liu, Shuyan and Schad, Daniel and Kuschpel, Maxim S. and Rapp, Michael A. and Heinz, Andreas}, title = {Music and Video Gaming during Breaks}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-90700}, pages = {1 -- 12}, year = {2016}, abstract = {Different systems for habitual versus goal-directed control are thought to underlie human decision-making. Working memory is known to shape these decision-making systems and their interplay, and is known to support goal-directed decision making even under stress. Here, we investigated if and how decision systems are differentially influenced by breaks filled with diverse everyday life activities known to modulate working memory performance. We used a within-subject design where young adults listened to music and played a video game during breaks interleaved with trials of a sequential two-step Markov decision task, designed to assess habitual as well as goal-directed decision making. Based on a neurocomputational model of task performance, we observed that for individuals with a rather limited working memory capacity video gaming as compared to music reduced reliance on the goal-directed decision-making system, while a rather large working memory capacity prevented such a decline. Our findings suggest differential effects of everyday activities on key decision-making processes.}, language = {en} } @article{GarbusowSchadSommeretal.2014, author = {Garbusow, Maria and Schad, Daniel and Sommer, Christian and Juenger, Elisabeth and Sebold, Miriam and Friedel, Eva and Wendt, Jean and Kathmann, Norbert and Schlagenhauf, Florian and Zimmermann, Ulrich S. and Heinz, Andreas and Huys, Quentin J. M. and Rapp, Michael A.}, title = {Pavlovian-to-instrumental transfer in alcohol dependence: a pilot study}, series = {Neuropsychobiology : international journal of experimental and clinical research in biological psychiatry, pharmacopsychiatry, Biological Psychology/Pharmacopsychology and Pharmacoelectroencephalography}, volume = {70}, journal = {Neuropsychobiology : international journal of experimental and clinical research in biological psychiatry, pharmacopsychiatry, Biological Psychology/Pharmacopsychology and Pharmacoelectroencephalography}, number = {2}, publisher = {Karger}, address = {Basel}, issn = {0302-282X}, doi = {10.1159/000363507}, pages = {111 -- 121}, year = {2014}, abstract = {Background: Pavlovian processes are thought to play an important role in the development, maintenance and relapse of alcohol dependence, possibly by influencing and usurping ongoing thought and behavior. The influence of pavlovian stimuli on ongoing behavior is paradigmatically measured by pavlovian-to-instrumental transfer (PIT) tasks. These involve multiple stages and are complex. Whether increased PIT is involved in human alcohol dependence is uncertain. We therefore aimed to establish and validate a modified PIT paradigm that would be robust, consistent and tolerated by healthy controls as well as by patients suffering from alcohol dependence, and to explore whether alcohol dependence is associated with enhanced PIT. Methods: Thirty-two recently detoxified alcohol-dependent patients and 32 age- and gender-matched healthy controls performed a PIT task with instrumental go/no-go approach behaviors. The task involved both pavlovian stimuli associated with monetary rewards and losses, and images of drinks. Results: Both patients and healthy controls showed a robust and temporally stable PIT effect. Strengths of PIT effects to drug-related and monetary conditioned stimuli were highly correlated. Patients more frequently showed a PIT effect, and the effect was stronger in response to aversively conditioned CSs (conditioned suppression), but there was no group difference in response to appetitive CSs. Conclusion: The implementation of PIT has favorably robust properties in chronic alcohol-dependent patients and in healthy controls. It shows internal consistency between monetary and drug-related cues. The findings support an association of alcohol dependence with an increased propensity towards PIT.}, language = {en} } @article{SchadGarbusowFriedeletal.2018, author = {Schad, Daniel and Garbusow, Maria and Friedel, Eva and Sommer, Christian and Sebold, Miriam and H{\"a}gele, Claudia and Bernhardt, Nadine and Nebe, Stephan and Kuitunen-Paul, S{\"o}ren and Liu, Shuyan and Eichmann, Uta and Beck, Anne and Wittchen, Hans-Ulrich and Walter, Henrik and Sterzer, Philipp and Zimmermann, Ulrich S. and Smolka, Michael N. and Schlagenhauf, Florian and Huys, Quentin J. M. and Heinz, Andreas and Rapp, Michael A.}, title = {Neural correlates of instrumental responding in the context of alcohol-related cues index disorder severity and relapse risk}, series = {European archives of psychiatry and clinical neuroscience : official organ of the German Society for Biological Psychiatry}, volume = {269}, journal = {European archives of psychiatry and clinical neuroscience : official organ of the German Society for Biological Psychiatry}, number = {3}, publisher = {Springer}, address = {Heidelberg}, issn = {0940-1334}, doi = {10.1007/s00406-017-0860-4}, pages = {295 -- 308}, year = {2018}, abstract = {The influence of Pavlovian conditioned stimuli on ongoing behavior may contribute to explaining how alcohol cues stimulate drug seeking and intake. Using a Pavlovian-instrumental transfer task, we investigated the effects of alcohol-related cues on approach behavior (i.e., instrumental response behavior) and its neural correlates, and related both to the relapse after detoxification in alcohol-dependent patients. Thirty-one recently detoxified alcohol-dependent patients and 24 healthy controls underwent instrumental training, where approach or non-approach towards initially neutral stimuli was reinforced by monetary incentives. Approach behavior was tested during extinction with either alcohol-related or neutral stimuli (as Pavlovian cues) presented in the background during functional magnetic resonance imaging (fMRI). Patients were subsequently followed up for 6 months. We observed that alcohol-related background stimuli inhibited the approach behavior in detoxified alcohol-dependent patients (t = -3.86, p < .001), but not in healthy controls (t = -0.92, p = .36). This behavioral inhibition was associated with neural activation in the nucleus accumbens (NAcc) (t((30)) = 2.06, p < .05). Interestingly, both the effects were only present in subsequent abstainers, but not relapsers and in those with mild but not severe dependence. Our data show that alcohol-related cues can acquire inhibitory behavioral features typical of aversive stimuli despite being accompanied by a stronger NAcc activation, suggesting salience attribution. The fact that these findings are restricted to abstinence and milder illness suggests that they may be potential resilience factors.}, language = {en} } @article{SekutowiczGuggenmosKuitunenPauletal.2019, author = {Sekutowicz, Maria and Guggenmos, Matthias and Kuitunen-Paul, S{\"o}ren and Garbusow, Maria and Sebold, Miriam and Pelz, Patricia and Priller, Josef and Wittchen, Hans-Ulrich and Smolka, Michael N. and Zimmermann, Ulrich S. and Heinz, Andreas and Sterzer, Philipp and Schmack, Katharina}, title = {Neural Response Patterns During Pavlovian-to-Instrumental Transfer Predict Alcohol Relapse and Young Adult Drinking}, series = {Biological psychiatry : a journal of psychiatric neuroscience and therapeutics ; a publication of the Society of Biological Psychiatry}, volume = {86}, journal = {Biological psychiatry : a journal of psychiatric neuroscience and therapeutics ; a publication of the Society of Biological Psychiatry}, number = {11}, publisher = {Elsevier}, address = {New York}, issn = {0006-3223}, doi = {10.1016/j.biopsych.2019.06.028}, pages = {857 -- 863}, year = {2019}, abstract = {BACKGROUND: Pavlovian-to-instrumental transfer (PIT) describes the influence of conditioned stimuli on instrumental behaviors and is discussed as a key process underlying substance abuse. Here, we tested whether neural responses during alcohol-related PIT predict future relapse in alcohol-dependent patients and future drinking behavior in adolescents. METHODS: Recently detoxified alcohol-dependent patients (n = 52) and young adults without dependence (n = 136) underwent functional magnetic resonance imaging during an alcohol-related PIT paradigm, and their drinking behavior was assessed in a 12-month follow-up. To predict future drinking behavior from PIT activation patterns, we used a multivoxel classification scheme based on linear support vector machines. RESULTS: When training and testing the classification scheme in patients, PIT activation patterns predicted future relapse with 71.2\% accuracy. Feature selection revealed that classification was exclusively based on activation patterns in medial prefrontal cortex. To probe the generalizability of this functional magnetic resonance imaging-based prediction of future drinking behavior, we applied the support vector machine classifier that had been trained on patients to PIT functional magnetic resonance imaging data from adolescents. An analysis of cross-classification predictions revealed that those young social drinkers who were classified as abstainers showed a greater reduction in alcohol consumption at 12-month follow-up than those classified as relapsers (Delta = -24.4 +/- 6.0 g vs. -5.7 +/- 3.6 g; p = .019). CONCLUSIONS: These results suggest that neural responses during PIT could constitute a generalized prognostic marker for future drinking behavior in established alcohol use disorder and in at-risk states.}, language = {en} } @misc{GarbusowSommerNebeetal.2018, author = {Garbusow, Maria and Sommer, C. and Nebe, S. and Sebold, Miriam and Kuitunen-Paul, S{\"o}ren and Wittchen, H. U. and Smolka, M. and Zimmermann, U. and Rapp, Michael A. and Huys, Q. and Schlagenhauf, Florian and Heinz, A.}, title = {Pavlovian-instrumental transfer in the course of alcohol use disorder}, series = {European psychiatry : the journal of the Association of European Psychiatrists}, volume = {48}, journal = {European psychiatry : the journal of the Association of European Psychiatrists}, publisher = {Elsevier}, address = {ISSY-LES-MOULINEAUX}, issn = {0924-9338}, pages = {S546 -- S546}, year = {2018}, abstract = {Background: Pavlovian processes are thought to play an important role in the development, maintenance and relapse of alcohol dependence, possibly by influencing and usurping on- going thought and behavior. The influence of Pavlovian stimuli on on-going behavior is paradigmatically measured by Pavlovian-to-instrumental-transfer (PIT) tasks. These involve multiple stages and are complex. Whether increased PIT is involved in human alcohol dependence is uncertain. We therefore aimed to establish and validate a modified PIT paradigm that would be robust, consistent, and tolerated by healthy controls as well as by patients suffering from alcohol dependence, and to explore whether alcohol dependence is associated with enhanced Pavlovian-Instrumental transfer. Methods: 32 recently detoxified alcohol-dependent patients and 32 age and gender matched healthy controls performed a PIT task with instrumental go/no-go approach behaviours. The task involved both Pavlovian stimuli associated with monetary rewards and losses, and images of drinks. Results: Both patients and healthy controls showed a robust and temporally stable PIT effect. Strengths of PIT effects to drug-related and monetary conditioned stimuli were highly correlated. Patients more frequently showed a PIT effect and the effect was stronger in response to aversively conditioned CSs (conditioned suppression), but there was no group difference in response to appetitive CSs. Conclusion: The implementation of PIT has favorably robust properties in chronic alcohol- dependent patients and in healthy controls. It shows internal consistency between monetary and drug-related cues. The findings support an association of alcohol dependence with an increased propensity towards PIT.}, language = {en} } @article{SeboldSchadNebeetal.2016, author = {Sebold, Miriam and Schad, Daniel and Nebe, Stephan and Garbusow, Maria and Juenger, Elisabeth and Kroemer, Nils B. and Kathmann, Norbert and Zimmermann, Ulrich S. and Smolka, Michael N. and Rapp, Michael A. and Heinz, Andreas and Huys, Quentin J. M.}, title = {Pavlovian-to-Instrumental Transfer Effects Rely Less on Model-based Reinforcement Learning}, series = {Journal of cognitive neuroscience}, volume = {28}, journal = {Journal of cognitive neuroscience}, publisher = {MIT Press}, address = {Cambridge}, issn = {0898-929X}, doi = {10.1162/jocn_a_00945}, pages = {985 -- 995}, year = {2016}, abstract = {Behavioral choice can be characterized along two axes. One axis distinguishes reflexive, model-free systems that slowly accumulate values through experience and a model-based system that uses knowledge to reason prospectively. The second axis distinguishes Pavlovian valuation of stimuli from instrumental valuation of actions or stimulus-action pairs. This results in four values and many possible interactions between them, with important consequences for accounts of individual variation. We here explored whether individual variation along one axis was related to individual variation along the other. Specifically, we asked whether individuals' balance between model-based and model-free learning was related to their tendency to show Pavlovian interferences with instrumental decisions. In two independent samples with a total of 243 participants, Pavlovian-instrumental transfer effects were negatively correlated with the strength of model-based reasoning in a two-step task. This suggests a potential common underlying substrate predisposing individuals to both have strong Pavlovian interference and be less model-based and provides a framework within which to interpret the observation of both effects in addiction.}, language = {en} } @article{KuschpelLiuSchadetal.2015, author = {Kuschpel, Maxim S. and Liu, Shuyan and Schad, Daniel and Heinzel, Stephan and Heinz, Andreas and Rapp, Michael A.}, title = {Differential effects of wakeful rest, music and video game playing on working memory performance in the n-back task}, series = {Frontiers in psychology}, journal = {Frontiers in psychology}, number = {6}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2015.01683}, year = {2015}, abstract = {The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on working memory performance. Young adults were exposed to breaks involving (i) eyes-open resting, (ii) listening to music and (iii) playing the video game "Angry Birds" before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the "Angry Birds" video game during a short learning break led to a decline in task performance over the course of the task as compared to eyes-open resting and listening to music, although overall task performance was not impaired. This effect was associated with high levels of daily mind wandering and low self-reported ability to concentrate. These findings indicate that video games can negatively affect working memory performance over time when played in between learning tasks. We suggest further investigation of these effects because of their relevance to everyday activity.}, language = {en} } @article{SchadJuengerSeboldetal.2014, author = {Schad, Daniel and Juenger, Elisabeth and Sebold, Miriam and Garbusow, Maria and Bernhardt, Nadine and Javadi, Amir-Homayoun and Zimmermann, Ulrich S. and Smolka, Michael N. and Heinz, Andreas and Rapp, Michael A. and Huys, Quentin J. M.}, title = {Processing speed enhances model-based over model-free reinforcement learning in the presence of high working memory functioning}, series = {Frontiers in psychology}, volume = {5}, journal = {Frontiers in psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2014.01450}, pages = {10}, year = {2014}, abstract = {Theories of decision-making and its neural substrates have long assumed the existence of two distinct and competing valuation systems, variously described as goal-directed vs. habitual, or, more recently and based on statistical arguments, as model-free vs. model-based reinforcement-learning. Though both have been shown to control choices, the cognitive abilities associated with these systems are under ongoing investigation. Here we examine the link to cognitive abilities, and find that individual differences in processing speed covary with a shift from model-free to model-based choice control in the presence of above-average working memory function. This suggests shared cognitive and neural processes; provides a bridge between literatures on intelligence and valuation; and may guide the development of process models of different valuation components. Furthermore, it provides a rationale for individual differences in the tendency to deploy valuation systems, which may be important for understanding the manifold neuropsychiatric diseases associated with malfunctions of valuation.}, language = {en} } @article{SeboldGarbusowJetzschmannetal.2019, author = {Sebold, Miriam and Garbusow, Maria and Jetzschmann, P. and Schad, Daniel and Nebe, S. and Schlagenhauf, Florian and Heinz, A. and Rapp, Michael A. and Romanczuk-Seiferth, Nina}, title = {Reward and avoidance learning in the context of aversive environments and possible implications for depressive symptoms}, series = {Psychopharmacology}, volume = {236}, journal = {Psychopharmacology}, number = {8}, publisher = {Springer}, address = {New York}, issn = {0033-3158}, doi = {10.1007/s00213-019-05299-9}, pages = {2437 -- 2449}, year = {2019}, abstract = {Background Aversive stimuli in the environment influence human actions. This includes valence-dependent influences on action selection, e.g., increased avoidance but decreased approach behavior. However, it is yet unclear how aversive stimuli interact with complex learning and decision-making in the reward and avoidance domain. Moreover, the underlying computational mechanisms of these decision-making biases are unknown. Methods To elucidate these mechanisms, 54 healthy young male subjects performed a two-step sequential decision-making task, which allows to computationally model different aspects of learning, e.g., model-free, habitual, and model-based, goal-directed learning. We used a within-subject design, crossing task valence (reward vs. punishment learning) with emotional context (aversive vs. neutral background stimuli). We analyzed choice data, applied a computational model, and performed simulations. Results Whereas model-based learning was not affected, aversive stimuli interacted with model-free learning in a way that depended on task valence. Thus, aversive stimuli increased model-free avoidance learning but decreased model-free reward learning. The computational model confirmed this effect: the parameter lambda that indicates the influence of reward prediction errors on decision values was increased in the punishment condition but decreased in the reward condition when aversive stimuli were present. Further, by using the inferred computational parameters to simulate choice data, our effects were captured. Exploratory analyses revealed that the observed biases were associated with subclinical depressive symptoms. Conclusion Our data show that aversive environmental stimuli affect complex learning and decision-making, which depends on task valence. Further, we provide a model of the underlying computations of this affective modulation. Finally, our finding of increased decision-making biases in subjects reporting subclinical depressive symptoms matches recent reports of amplified Pavlovian influences on action selection in depression and suggests a potential vulnerability factor for mood disorders. We discuss our findings in the light of the involvement of the neuromodulators serotonin and dopamine.}, language = {en} } @article{FriedelSeboldKuitunenPauletal.2017, author = {Friedel, Eva and Sebold, Miriam and Kuitunen-Paul, S{\"o}ren and Nebe, Stephan and Veer, Ilya M. and Zimmermann, Ulrich S. and Schlagenhauf, Florian and Smolka, Michael N. and Rapp, Michael A. and Walter, Henrik and Heinz, Andreas}, title = {How Accumulated Real Life Stress Experience and Cognitive Speed Interact on Decision-Making Processes}, series = {Frontiers in human neuroscienc}, volume = {11}, journal = {Frontiers in human neuroscienc}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-5161}, doi = {10.3389/fnhum.2017.00302}, pages = {1 -- 9}, year = {2017}, abstract = {Rationale: Advances in neurocomputational modeling suggest that valuation systems for goal-directed (deliberative) on one side, and habitual (automatic) decision-making on the other side may rely on distinct computational strategies for reinforcement learning, namely model-free vs. model-based learning. As a key theoretical difference, the model-based system strongly demands cognitive functions to plan actions prospectively based on an internal cognitive model of the environment, whereas valuation in the model-free system relies on rather simple learning rules from operant conditioning to retrospectively associate actions with their outcomes and is thus cognitively less demanding. Acute stress reactivity is known to impair model-based but not model-free choice behavior, with higher working memory capacity protecting the model-based system from acute stress. However, it is not clear which impact accumulated real life stress has on model-free and model-based decision systems and how this influence interacts with cognitive abilities. Methods: We used a sequential decision-making task distinguishing relative contributions of both learning strategies to choice behavior, the Social Readjustment Rating Scale questionnaire to assess accumulated real life stress, and the Digit Symbol Substitution Test to test cognitive speed in 95 healthy subjects. Results: Individuals reporting high stress exposure who had low cognitive speed showed reduced model-based but increased model-free behavioral control. In contrast, subjects exposed to accumulated real life stress with high cognitive speed displayed increased model-based performance but reduced model-free control. Conclusion: These findings suggest that accumulated real life stress exposure can enhance reliance on cognitive speed for model-based computations, which may ultimately protect the model-based system from the detrimental influences of accumulated real life stress. The combination of accumulated real life stress exposure and slower information processing capacities, however, might favor model-free strategies. Thus, the valence and preference of either system strongly depends on stressful experiences and individual cognitive capacities.}, language = {en} }