Filtern
Volltext vorhanden
- ja (5)
Gehört zur Bibliographie
- ja (5)
Dokumenttyp
- Dissertation (5) (entfernen)
Sprache
- Englisch (5) (entfernen)
Schlagworte
- emotion (5) (entfernen)
Institut
Are there emotional reactions towards social robots? Could you love a robot? Or, put the other way round: Could you mistreat a robot, tear it apart and sell it? Media reports people honoring military robots with funerals, mourning the “death” of a robotic dog, and granting the humanoid robot Sophia citizenship. But how profound are these reactions? Three experiments take a closer look on emotional reactions towards social robots by investigating the subjective experience of people as well as the motor expressive level. Contexts of varying degrees of Human-Robot Interaction (HRI) sketch a nuanced picture of emotions towards social robots that encompass conscious as well as unconscious reactions. The findings advance the understanding of affective experiences in HRI. It also turns the initial question into: Can emotional reactions towards social robots even be avoided?
In addition to bradykinesia and tremor, patients with Parkinson’s disease (PD) are known to exhibit non-motor symptoms such as apathy and hypomimia but also impulsivity in response to dopaminergic replacement therapy. Moreover, a plethora of studies observe differences in electrocortical and autonomic responses to both visual and acoustic affective stimuli in PD subjects compared to healthy controls. This suggests that the basal ganglia (BG), as well as the hyperdirect pathway and BG thalamocortical circuits, are involved in affective processing. Recent studies have shown valence and dopamine-dependent changes in synchronization in the subthalamic nucleus (STN) in PD patients during affective tasks. This thesis investigates the role of dopamine, valence, and laterality in STN electrophysiology by analyzing event-related potentials (ERP), synchronization, and inter-hemispheric STN connectivity. STN recordings were obtained from PD patients with chronically implanted electrodes for deep brain stimulation during a passive affective picture presentation task. The STN exhibited valence-dependent ERP latencies and lateralized ‘high beta’ (28–40 Hz) event-related desynchronization. This thesis also examines the role of dopamine, valence, and laterality on STN functional connectivity with the anterior cingulate cortex (ACC) and the amygdala. The activity of these limbic structures was reconstructed using simultaneously recorded electroencephalographic signals. While the STN was found to establish early coupling with both structures, STN-ACC coupling in the ‘alpha’ range (7–11 Hz) and uncoupling in the ‘low beta’ range (14–21 Hz) were lateralized. Lateralization was also observed at the level of synchrony in both reconstructed sources and for ACC ERP amplitude, whereas dopamine modulated ERP latency in the amygdala. These results may deepen our current understanding of the STN as a limbic node within larger emotional-motor networks in the brain.
Just do it! Guilt as a moral intuition to cooperate - A parallel constraint satisfaction approach
(2011)
After a long dominance of rational models of judgment and decision-making in moral psychology (e.g. Kohlberg, 1969) there is now a strong interest in how intuitions and emotions influence moral judgments and decisions (e.g. Greene, 2007; Haidt, 2001; Monin, Pizarro, & Beer, 2007). In the literature, the influence of emotions on moral decisions is explained by heuristic or non-compensatory information processing (e.g. Sinnott-Armstrong, Young, & Cushman, 2010; Sunstein, 2005; Tobler, Kalis, & Kalenscher, 2008). However, the process of emotion elicitation is ignored. Appraisal theories postulate that emotion elicitation is due to the incoherence (or discrepancy) of behavioral representations like goals and actions (Moors, 2009). Emotion elicitation and intuitive decision-making can be combined if both processes apply a connectionist information processing structure (e.g. Barnes & Thagard, 1996). The current work contrasts both perspectives of intuitive-emotional decision-making with respect to guilt and cooperation.
The present work investigated the neural mechanisms underlying cognitive inhibition/thought suppression in Anderson’s and Green’s Think/No-Think paradigm (TNT), as well as different variables influencing these mechanisms at the cognitive, the neurophysiological, the electrophysiological and the molecular level. Neurophysiological data collected with fNIRS and fMRI have added up to the existing evidence of a fronto-hippocampal network interacting during the inhibition of unwanted thoughts. Some evidence has been presented suggesting that by means of external stimulation of the right dlPFC through iTBS thought suppression might be improved, providing further evidence for an implication of this region in the TNT. A combination of fNIRS with ERP has delivered evidence of a dissociation of early condition-independent attentional and later suppression-specific processes within the dlPFC, both contributing to suppression performance. Due to inconsistencies in the previous literature it was considered how stimulus valence would influence thought suppression by manipulating the emotional content of the to-be-suppressed stimuli. Findings of the current work regarding the ability to suppress negative word or picture stimuli have, however, been inconclusive as well. It has been hypothesized that performance in the TNT might depend on the combination of valence conditions included in the paradigm. Alternatively, it has been suggested that inconsistent findings regarding the suppression of negative stimuli or suppression at all might be due to certain personality traits and/or genetic variables, found in the present work to contribute to thought inhibition in the TNT. Rumination has been shown to be a valid predictor of thought suppression performance. Increased ruminative tendencies led to worse suppression performance which, in the present work, has been linked to less effective recruitment of the dlPFC and in turn less effective down-regulation of hippocampal activity during suppression trials. Trait anxiety has also been shown to interrupt thought suppression despite higher, however, inefficient recruitment of the dlPFC. Complementing the findings regarding ruminative tendencies and decreased thought inhibition a functional polymorphism in the KCNJ6 gene, encompassing a G-to-A transition, has been shown to disrupt thought suppression despite increased activation of the dlPFC. Through the investigation of thought suppression at different levels, the current work adds further evidence to the idea that the TNT reflects an executive control mechanism, which is sensitive to alterations in stimulus valence to some extent, neurophysiological functioning as indicated by its sensitivity to iTBS, functional modulations at the molecular level and personality traits, such as rumination and trait anxiety.
Humans have the tendency to react with congruent facial expressions when looking at an emotional face. Interestingly, recent studies revealed that several situational moderators can modulate strength and direction of these reactions. In current literature, congruent facial reactions to emotional facial expressions are usually described in terms of “facial mimicry” and interpreted as imitative behavior. Thereby, facial mimicry is understood as a process of pure motor resonance resulting from overlapping representations for the perception and the execution of a certain behavior. Motor mimicry, however, is not the only mechanism by which congruent facial reactions can occur. Numerous studies have shown that facial muscles also indicate valence evaluations. Furthermore, facial reactions are also determined by our current emotional state. These thoughts suggest that the modulation of congruent facial reactions to emotional expressions can be based on both motor and affective processes. However, a separation of motor and affective processes in facial reactions is hard to make. None of the published studies that tried that could show a clear involvement of one or the other process so far. Therefore, the aim of the present line of experiments is to shed light on the involvement of motor and affective processes in the modulation of congruent and incongruent facial reactions. Specifically, the experiments are designed to test the assumptions of a working model on mechanisms underlying the modulation of facial reactions and to examine the neuronal correlates involved in such modulations with a broad range of methods. Experiments 1 and 2 experimentally manipulate motor and affective mechanisms by using specific contexts. In the chose settings, motor process models and affective models of valence evaluations make competing predictions about resulting facial reactions. The results of Experiment 1 did not support the involvement of valence evaluations in the modulation of congruent and incongruent facial reactions to facial expressions. The results of Experiments 2a and 2b suggest that emotional reactions are the predominant determinant of facial reactions. Experiment 3 aimed at identifying the psychological mediators that indicate motor and affective mechanisms. Motor mechanisms are assessed via the psychological mediator empathy. Additionally, as a psychological mediator for clarifying the role of affective mechanisms subjective measures of the participants’ current emotional state in response to the presented facial expressions were taken. Mediational analyses show that the modulation of congruent facial reactions can be explained by a decrease of state cognitive empathy. This suggests that motor processes mediate the effects of the context on congruent facial reactions. However, such a mechanism could not be observed for incongruent reactions. Instead, it was found that affective processes in terms of emotional reactions are involved in incongruent facial reactions. Additionally, the involvement of a third class of processes, namely strategic processes, was observed. Experiment 4 aimed at investigating whether a change in the strength of perception can explain the contextual modulation of facial reactions to facial expressions. According to motor process models the strength of perception is directly related to the strength of the spread of activation from perception to the execution of an action and thereby to the strength of the resulting mimicry behavior. The results suggest that motor mechanisms were involved in the modulation of congruent facial reactions by attitudes. Such an involvement of motor mechanisms could, however, not be observed for the modulation of incongruent reactions. In Experiment 5 the investigation of neuronal correlates shall be extended to the observation of involved brain areas via fMRI. The proposed brain areas depicting motor areas were prominent parts of the mirror neuron system. The regions of interest depicting areas involved in the affective processing were amygdala, insula, striatum. Furthermore, it could be shown that changes in the activity of parts of the MNS are related to the modulation of congruent facial reactions. Further on, results revealed the involvement of affective processes in the modulation of incongruent facial reactions. In sum, these results lead to a revised working model on the mechanisms underlying the modulation of facial reactions to emotional facial expressions. The results of the five experiments provide strong support for the involvement of motor mechanisms in congruent facial reactions. No evidence was found for the involvement of motor mechanisms in the occurrence or modulation of incongruent facial reactions. Furthermore, no evidence was found for the involvement of valence evaluations in the modulation of facial reactions. Instead, emotional reactions were found to be involved in the modulation of mainly incongruent facial reactions.