The distractor-response binding effect (Frings & Rothermund, 2011; Frings, Rothermund, & Wentura, 2007; Rothermund, Wentura, & De Houwer, 2005) is based on the idea that irrelevant information will be integrated with the response to the relevant stimuli in an episodic memory trace. The immediate re-encounter of any aspect of this saved episode " be it relevant or irrelevant " can lead to retrieval of the whole episode. As a consequence, the previously executed and now retrieved response may influencing the response to the current relevant stimulus. That is, the current response may either be facilitated or be impaired by the retrieved response, depending on whether it is compatible or incompatible to the currently demanded response. Previous research on this kind of episodic retrieval focused on the influence on action control. I examined if distractor response binding also plays a role in decision making in addition to action control. To this end I adapted the distractor-to-distractor priming paradigm (Frings et al., 2007) and conducted nine experiments in which participants had to decide as fast as possible which disease a fictional patient suffered from. To infer the correct diagnosis, two cues were presented; one did not give any hint for a disease (the irrelevant cue), whereas the other did (the relevant cue). Experiments 1a to 1c showed that the distractor-response binding effect is present in deterministic decision situations. Further, experiments 2a and 2b indicate that distractor-response binding also influences decisions under uncertainty. Finally, experiments 3a to 3d were conducted to test some constraints and underlying mechanisms of the distractor-response binding effect in decision making under uncertainty. In sum, these nine experiments provide strong evidence that distractor-response binding influences decision making.

Every day we are exposed to a large set of appetitive food cues, mostly of high caloric, high carbohydrate content. Environmental factors like food cue exposition can impact eating behavior, by triggering anticipatory endocrinal responses and reinforcing the reward value of food. Additionally, it has been shown that eating behavior is largely influence by neuroendocrine factors. Energy homeostasis is of great importance for survival in all animal species. It is challenged under the state of food deprivation which is considered to be a metabolic stressor. Interestingly, the systems regulating stress and food intake share neural circuits. Adrenal glucocorticoids, as cortisol, and the pancreatic hormone insulin have been shown to be crucial to maintain catabolic and anabolic balance. Cortisol and insulin can cross the blood-brain barrier and interact with receptors distributed throughout the brain, influencing appetite and eating behavior. At the same time, these hormones have an important impact on the stress response. The aim of the current work is to broaden the knowledge on reward related food cue processing. With that purpose, we studied how food cue processing is influenced by food deprivation in women (in different phases of the menstrual cycle) and men. Furthermore, we investigated the impact of the stress/metabolic hormones, insulin and cortisol, at neural sites important for energy metabolism and in the processing of visual food cues. The Chapter I of this thesis details the underlying mechanisms of the startle response and its application in the investigation of food cue processing. Moreover, it describes the effects of food deprivation and of the stress-metabolic hormones insulin and cortisol in reward related processing of food cues. It explains the rationale for the studies presented in Chapter II-IV and describes their main findings. A general discussion of the results and recommendations for future research is given. In the study described in Chapter II, startle methodology was used to study the impact of food deprivation in the processing of reward related food cues. Women in different phases of the menstrual cycle and men were studied, in order to address potential effects of sex and menstrual cycle. All participants were studied either satiated or food deprived. Food deprivation provoked enhanced acoustic startle (ASR) response during foreground presentation of visual food cues. Sex and menstrual cycle did not influence this effect. The startle pattern towards food cues during fasting can be explained by a frustrative nonreward effect (FNR), driven by the impossibility to consume the exposed food. In Chapter III, a study is described, which was carried out to explore the central effects of insulin and cortisol, using continuous arterial spin labeling to map cerebral blood flow patterns. Following standardized periods of fasting, male participants received either intranasal insulin, oral cortisol, both, or placebo. Intranasal insulin increased resting regional cerebral blood flow in the putamen and insular cortex, structures that are involved in the regulation of eating behavior. Neither cortisol nor interaction effects were found. These results demonstrate that insulin exerts an action in metabolic centers during resting state, which is not affected by glucocorticoids. The study described in Chapter IV uses a similar pharmacological manipulation as the one presented in Chapter III, while assessing processing of reward related food cues through the startle paradigm validated in Chapter II. A sample of men was studied during short-term food deprivation. Considering the importance of both cortisol and insulin in glucose metabolism, food pictures were divided by glycemic index. Cortisol administration enhanced ASR during foreground presentation of "high glycemic" food pictures. This result suggests that cortisol provokes an increase in reward value of high glycemic food cues, which is congruent with previous research on stress and food consumption. This thesis gives support to the FNR hypothesis towards food cues during states of deprivation. Furthermore, it highlights the potential effects of stress related hormones in metabolism-connected neuronal structures, and in the reward related mechanisms of food cue processing. In a society marked by increased food exposure and availability, alongside with increased stress, it is important to better understand the impact of food exposition and its interaction with relevant hormones. This thesis contributes to the knowledge in this field. More research in this direction is needed.

Stress has been considered one of the most relevant factors promoting aggressive behavior. Animal and human pharmacological studies revealed the stress hormones corticosterone in rodents and cortisol in humans to constitute a particularly important neuroendocrine determinate in facilitating aggression and beyond that, assumedly in its continuation and escalation. Moreover, cortisol-induced alterations of social information processing, as well as of cognitive control processes, have been hypothesized as possible influencing factors in the stress-aggression link. So far, the immediate impact of a preceding stressor and thereby stress-induced rise of cortisol on aggressive behavior as well as higher-order cognitive control processes and social information processing in this context have gone mostly unheeded. The present thesis aimed to extend the hitherto findings of stress and aggression in this regard. For this purpose two psychophysiological studies with healthy adults were carried out, both using the socially evaluated-cold pressor test as an acute stress induction. Additionally to behavioral data and subjective reports, event related potentials were measured and acute levels of salivary cortisol were collected on the basis of which stressed participants were divided into cortisol-responders and "nonresponders. Study 1 examined the impact of acute stress-induced cortisol increase on inhibitory control and its neural correlates. 41 male participants were randomly assigned to the stress procedure or to a non-stressful control condition. Beforehand and afterwards, participants performed a Go Nogo task with visual letters to measure response inhibition. The effect of acute stress-induced cortisol increase on covert and overt aggressive behavior and on the processing of provoking stimuli within the aggressive encounter was investigated in study 2. Moreover, this experiment examined the combined impact of stress and aggression on ensuing affective information processing. 71 male and female participants were either exposed to the stress or to the control condition. Following this, half of each group received high or low levels of provocation during the Taylor Aggression Paradigm. At the end of the experiment, a passive viewing paradigm with affective pictures depicting positive, negative, or aggressive scenes with either humans or objects was realized. The results revealed that men were not affected by a stress-induced rise in cortisol on a behavioral level, showing neither impaired response inhibition nor enhanced aggressive behavior. In contrast, women showed enhanced overt and covert aggressive behavior under a surge of endogenous cortisol, confirming previous results, albeit only in case of high provocation and only up to the level of the control group. Unlike this rather moderate impact on behavior, cortisol showed a distinct impact on neural correlates of information processing throughout inhibitory control, aggression-eliciting stimuli, and emotional pictures for both men and women. At this, stress-induced increase of cortisol resulted in enhanced N2 amplitudes to Go stimuli, whereas P2 amplitudes to both and N2 to Nogo amplitudes retained unchanged, indicating an overcorrection and caution of the response activation in favor of successful inhibitory control. The processing of aggression-eliciting stimuli during the aggressive encounter was complexly altered by stress differently for women and men. Under increased cortisol levels, the frontal or parietal P3 amplitude patterns were either diminished or reversed in the case of high provocation compared to the control group and to cortisol-nonresponders, indicating a desensitization towards aggression-eliciting stimuli in males, but a more elaborate processing of those in women. Moreover, stress-induced cortisol and provocation jointly altered subsequent affective information processing at early as well as later stages of the information processing stream. Again, increased levels of cortisol led opposite directed amplitudes in the case of high provocation relative to the control group and cortisol-nonresponders, with enhanced N2 amplitudes in men and reduced P3 and LPP amplitudes in men and women for all affective pictures, suggesting initially enhanced emotional reactivity in men, but ensuing reduced motivational attention and enhanced emotion regulation in both, men and women. As a result, these present findings confirm the relevance of HPA activity in the elicitation and persistence of human aggressive behavior. Moreover, they reveal the significance of compensatory and emotion regulatory strategies and mechanisms in response to stress and provocation, indorsing the relevance of social information and cognitive control processes. Still, more research is needed to clarify the conditions which lead to the facilitation of aggression and by which compensatory mechanisms this is prevented.

Evaluative conditioning (EC) refers to changes in liking that are due to the pairing of stimuli, and is one of the effects studied in order to understand the processes of attitude formation. Initially, EC had been conceived of as driven by processes that are unique to the formation of attitudes, and that occur independent of whether or not individuals engage in conscious and effortful propositional processes. However, propositional processes have gained considerable popularity as an explanatory concept for the boundary conditions observed in EC studies, with some authors going as far as to suggest that the evidence implies that EC is driven primarily by propositional processes. In this monograph I present research which questions the validity of this claim, and I discuss theoretical challenges and avenues for future EC research.