@misc{GarbusowSommerNebeetal.2018, author = {Garbusow, Maria and Sommer, Christian and Nebe, Stephan and Sebold, Miriam Hannah and Kuitunen-Paul, S{\"o}ren and Wittchen, Hans-Ulrich and Smolka, Michael N. and Zimmermann, Ulrich S. and Rapp, Michael Armin and Huys, Quentin J. M. and Schlagenhauf, Florian and Heinz, Andreas}, title = {Multi-level evidence of general pavlovian-to-instrumental transfer in alcohol use disorder}, series = {Alcoholism : clinical and experimental research ; the official journal of the American Medical Society on Alcoholism and the Research Society on Alcoholism}, volume = {42}, journal = {Alcoholism : clinical and experimental research ; the official journal of the American Medical Society on Alcoholism and the Research Society on Alcoholism}, publisher = {Wiley}, address = {Hoboken}, issn = {0145-6008}, pages = {128A -- 128A}, year = {2018}, language = {en} } @article{FriedelSeboldKuitunenPauletal.2017, author = {Friedel, Eva and Sebold, Miriam Hannah 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 Armin 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} } @article{ObstSchadHuysetal.2018, author = {Obst, Elisabeth and Schad, Daniel and Huys, Quentin J. M. and Sebold, Miriam Hannah and Nebe, Stephan and Sommer, Christian and Smolka, Michael N. and Zimmermann, Ulrich S.}, title = {Drunk decisions}, series = {Journal of Psychopharmacology}, volume = {32}, journal = {Journal of Psychopharmacology}, number = {8}, publisher = {Sage Publ.}, address = {London}, issn = {0269-8811}, doi = {10.1177/0269881118772454}, pages = {855 -- 866}, year = {2018}, abstract = {Background: Studies in humans and animals suggest a shift from goal-directed to habitual decision-making in addiction. We therefore tested whether acute alcohol administration reduces goal-directed and promotes habitual decision-making, and whether these effects are moderated by self-reported drinking problems. Methods: Fifty-three socially drinking males completed the two-step task in a randomised crossover design while receiving an intravenous infusion of ethanol (blood alcohol level=80 mg\%), or placebo. To minimise potential bias by long-standing heavy drinking and subsequent neuropsychological impairment, we tested 18- to 19-year-old adolescents. Results: Alcohol administration consistently reduced habitual, model-free decisions, while its effects on goal-directed, model-based behaviour varied as a function of drinking problems measured with the Alcohol Use Disorders Identification Test. While adolescents with low risk for drinking problems (scoring <8) exhibited an alcohol-induced numerical reduction in goal-directed choices, intermediate-risk drinkers showed a shift away from habitual towards goal-directed decision-making, such that alcohol possibly even improved their performance. Conclusions: We assume that alcohol disrupted basic cognitive functions underlying habitual and goal-directed decisions in low-risk drinkers, thereby enhancing hasty choices. Further, we speculate that intermediate-risk drinkers benefited from alcohol as a negative reinforcer that reduced unpleasant emotional states, possibly displaying a novel risk factor for drinking in adolescence.}, language = {en} }