Universitätsbibliothek

The present dissertation aims to shed light on different mechanisms of socio-emotional feedback in social decision-making situations. The objective is to evaluate emotional facial expressions as feedback stimuli, i.e., responses of interaction partners to certain social decisions. In addition to human faces, artificial emojis are also examined due to their relevance for modern digital communication. Previous research on the influence of emotional feedback suggests that a person's behavior can be effectively reinforced by rewarding stimuli. In the context of this dissertation, the differences in the feedback processing of human photographs and emojis, but also the evaluation of socially expected versus socially unexpected feedback were examined in detail in four studies. In addition to behavioral data, we used the electroencephalogram (EEG) in all studies to investigate neural correlates of social decision-making and emotional feedback. As the central paradigm, all studies were based on a modified ultimatum game. The game is structured as follows: there is a so-called proposer who holds a specific amount of money (e.g., 10 cents) and offers the responder a certain amount (e.g., 3 cents). The responder then decides whether to accept or reject the offer. In the version of the ultimatum game presented here, different types of proposers are introduced. After the participants have accepted or rejected in the role of the responder, the different proposers react to the participant’s decision with specific emotional facial expressions. Different feedback patterns are used for the individual experiments conducted in the course of this dissertation. In the first study, we investigated the influence of emotional feedback on decision-making in the modified version of the ultimatum game. We were able to show that a proposer who responds to the acceptance of an offer with a smiling face achieves more accepted offers overall than a control proposer who responds to both accepted and rejected offers with a neutral facial expression. Consequently, the smile served as a positive reinforcement. Similarly, a sad expression in response to a rejected offer also resulted in higher acceptance rates as compared to the control identity, which could be considered an expression of compassion for that proposer. On a neuronal level, we could show that there are differences between simply looking at negative emotional stimuli (i.e., sad and angry faces) and their appearance as feedback stimuli after rejected offers in the modified ultimatum game. The so-called feedback-related negativity was reduced (i.e., more positive) when negative emotions appeared as feedback from the proposers. We argued that these findings might show that the participants wanted to punish the proposers by rejecting an offer for its unfairness and therefore the negative feedback met their expectations. The altered processing of negative emotional facial expressions in the ultimatum game could therefore indicate that the punishment is interpreted as successful. This includes the expectation that the interaction partner will change his behavior in the future and eventually make fairer offers. In the second study we wanted to show that smiling and sad emojis as feedback stimuli in the modified ultimatum game can also lead to increased acceptance rates. Contrary to our assumptions, this effect could not be observed. At the neural level as well, the findings did not correspond to our assumptions and differed strongly from those of the first study. One finding, however, was that the neural P3 component showed how the use of emojis as feedback stimuli particularly characterizes certain types of proposers. This is supported by the fact that the P3 is increased for the proposer who rewards an acceptance with a smile as well as for the proposer who reacts to rejection with a sad emoji compared to the neutral control proposer. The third study examined the discrepancy between the findings of the first and second study. Accordingly, both humans and emojis representing the different proposers were presented in the ultimatum game. In addition, emojis were selected that showed a higher similarity to known emojis from common messenger services compared to the second study. We were able to replicate that the proposers in the ultimatum game, who reward an acceptance of the offer with a smile, led to an increased acceptance rate compared to the neutral control proposers. This difference is independent of whether the proposers are represented by emojis or human faces. With regard to the neural correlates, we were able to demonstrate that emojis and human faces differ strongly in their neural processing. Emojis showed stronger activation than human faces in the face-processing N170 component, the feedback-related negativity and the P3 component. We concluded that the results of the N170 and feedback-related negativity could indicate a signal for missing social information of emojis compared to faces. The increased P3 amplitude for emojis might imply that emojis appear unexpectedly as reward stimuli in a social decision task compared to human faces. The last study of this project dealt with socially unexpected feedback. In comparison to the first three studies, new proposer identities were implemented. In particular, the focus was on a proposer who reacted to the rejection of an offer unexpectedly with a smile and to the acceptance with a neutral facial expression. According to the results, participants approach this unexpected smile through increased rejection, although it is accompanied by financial loss. In addition, as reported in studies one and three, we were able to show that proposers who respond to the acceptance of an offer with a smiling face and thus meet the expectations of the participants have higher offer acceptance rates than the control proposer. At the neuronal level, especially the feedback from the socially unexpected proposer led to an increased P3 amplitude, which indicates that smiling after rejection is attributed a special subjective importance. The experiments provide new insights into the social influence through emotional feedback and the processing of relevant social cues. Due to the conceptual similarity of the studies, it was possible to differentiate between stable findings and potentially stimulus-dependent deviations, thus creating a well-founded contribution to the current research. Therefore, the novel paradigm presented here, and the knowledge gained from it could also play an important role in the future for clinical questions dealing with limited social competencies.

Sharing stories has become increasingly popular as a means to foster young children’s vocabulary development and to target early vocabulary gaps between disadvantaged children and their better-equipped peers. Although, in general, the beneficial effects of story interventions have been demonstrated (Marulis & Neuman, 2010, 2013), many factors possibly moderating those effects – including method of story delivery as well as questioning style – merit further examination (R. L. Walsh & Hodge, 2018). The aim of the present doctoral thesis was to test predictions from different theories on methods of story delivery and questioning styles regarding their influence on children’s vocabulary learning from listening to stories. Method of story delivery refers to the general way of how stories can be conveyed, with reading aloud and free-telling of stories (i.e., the narrator telling stories without reading from text) representing different approaches that are assumed to differ regarding narrator behavior and linguistic complexity. Questioning styles refer to different combinations of questions’ cognitive demand level (low vs. high vs. scaffolding-like increasing from low to high) and/or placement (within the story vs. after the story) during story sessions. In the present doctoral thesis, the first two studies (Studies 1 and 2) compared reading aloud and free-telling of stories as different methods of story delivery. Study 1 consisted of two experiments utilizing a within-subjects design with 3- to 6-year-old preschool children (Nexperiment1 = 83; Nexperiment2 = 48) listening to stories once either presented read aloud or freely told. Study 2 extended the first study by examining effects on story comprehension and additionally including audiotape versions of both story-delivery methods as experimental conditions, which allowed separating narrator behavior and linguistic complexity. With the second study being conducted as a between-subjects design, 4- to 6-year-old preschool children (N = 60) heard each of the stories twice, but listened only to one type of story delivery. The results of Study 1 indicated that no differences between methods of story delivery regarding word learning and child engagement were observable when narrator behavior in terms of eye contact and gesticulation was similar. However in Study 2, when free-telling was operationalized in a more naturalistic way, marked by higher rates of eye contact and gesticulation, it resulted in better child engagement, greater vocabulary learning, and better story comprehension than reading aloud. In contrast, as indicated by both studies, differences in linguistic complexity had no short-term impact on learning and comprehension. The studies, however, could not isolate the influence of eye contact versus gesture usage and could not distinguish between different types of gestures. The second set of studies (Studies 3 and 4) contrasted the effects of different types of question demand level (low vs. high vs. scaffolding-like increasing from low to high) and placement (within the story vs. after the story) and examined potential interactions with children’s cognitive skills. In one-to-one reading sessions (Study 3; N = 86) or small-group reading sessions (Study 4; N = 91) 4- to 6-year-old preschool children heard stories three times marked by different types of question demand level and placement or simply read-aloud without questions. The adult narrators encouraged the children to reflect on and answer questions (Study 1) and to give feedback on other children’s comments (Study 2), but in both studies, to ensure fidelity of the experimental conditions, the adult narrators did not provide corrective feedback or elaborate on the children’s answers. Results on measures of different facets of word learning indicated that asking questions resulted in better vocabulary learning than simply reading the stories aloud. However, in contrast to proposed hypotheses and across both studies, different types of question demand level and placement did not exert differential effects and they did not interact with children’s general vocabulary knowledge or memory skills. Thus, both studies suggest that those two types of questions features have no impact on children’s vocabulary learning, if questions are not followed up by narrator feedback and elaborations. However, whether different types of question placement and demand level produce differential learning gains through adult-child discussion following different questioning styles has still to be determined. Taken together, the four studies of the present doctoral thesis underline the central role that adults play for successful story sessions with young children not only for engaging children in the story but also for extending and for correcting their utterances. Although the presented studies extend existing knowledge about methods of story delivery and questioning styles during story sessions, further research needs to examine the impact of questioning styles on word learning through subsequent adult-child discussion and to gain a better understanding of the role of nonverbal narrator behavior during story delivery.

BACKGROUND: Thigmotaxis refers to a specific behavior of animals (i.e., to stay close to walls when exploring an open space). Such behavior can be assessed with the open field test (OFT), which is a well-established indicator of animal fear. The detection of similar open field behavior in humans may verify the translational validity of this paradigm. Enhanced thigmotaxis related to anxiety may suggest the relevance of such behavior for anxiety disorders, especially agoraphobia. METHODS: A global positioning system was used to analyze the behavior of 16 patients with agoraphobia and 18 healthy individuals with a risk for agoraphobia (i.e., high anxiety sensitivity) during a human OFT and compare it with appropriate control groups (n = 16 and n = 19). We also tracked 17 patients with agoraphobia and 17 control participants during a city walk that involved walking through an open market square. RESULTS: Our human OFT triggered thigmotaxis in participants; patients with agoraphobia and participants with high anxiety sensitivity exhibited enhanced thigmotaxis. This behavior was evident in increased movement lengths along the wall of the natural open field and fewer entries into the center of the field despite normal movement speed and length. Furthermore, participants avoided passing through the market square during the city walk, indicating again that thigmotaxis is related to agoraphobia. CONCLUSIONS: This study is the first to our knowledge to verify the translational validity of the OFT and to reveal that thigmotaxis, an evolutionarily adaptive behavior shown by most species, is related to agoraphobia, a pathologic fear of open spaces, and anxiety sensitivity, a risk factor for agoraphobia.

Immersive virtual reality is a powerful method to modify the environment and thereby influence experience. The present study used a virtual hand illusion and context manipulation in immersive virtual reality to examine top-down modulation of pain. Participants received painful heat stimuli on their forearm and placed an embodied virtual hand (co-located with their real one) under a virtual water tap, which dispensed virtual water under different experimental conditions. We aimed to induce a temperature illusion by a red, blue or white light suggesting warm, cold or no virtual water. In addition, the sense of agency was manipulated by allowing participants to have high or low control over the virtual hand’s movements. Most participants experienced a thermal sensation in response to the virtual water and associated the blue and red light with cool/cold or warm/hot temperatures, respectively. Importantly, the blue light condition reduced and the red light condition increased pain intensity and unpleasantness, both compared to the control condition. The control manipulation influenced the sense of agency, but did not influence pain ratings. The large effects revealed in our study suggest that context effects within an embodied setting in an immersive virtual environment should be considered within VR based pain therapy.

Objectives Virtual reality exposure therapy (VRET) is a promising treatment for patients with fear of driving. The present pilot study is the first one focusing on behavioral effects of VRET on patients with fear of driving as measured by a post-treatment driving test in real traffic. Methods The therapy followed a standardized manual including psychotherapeutic and medical examination, two preparative psychotherapy sessions, five virtual reality exposure sessions, a final behavioral avoidance test (BAT) in real traffic, a closing session, and two follow-up phone assessments after six and twelve weeks. VRE was conducted in a driving simulator with a fully equipped mockup. The exposure scenarios were individually tailored to the patients’ anxiety hierarchy. A total of 14 patients were treated. Parameters on the verbal, behavioral and physiological level were assessed. Results The treatment was helpful to overcome driving fear and avoidance. In the final BAT, all patients mastered driving tasks they had avoided before, 71% showed an adequate driving behavior as assessed by the driving instructor, and 93% could maintain their treatment success until the second follow-up phone call. Further analyses suggest that treatment reduces avoidance behavior as well as symptoms of posttraumatic stress disorder as measured by standardized questionnaires (Avoidance and Fusion Questionnaire: p < .10, PTSD Symptom Scale–Self Report: p < .05). Conclusions VRET in driving simulation is very promising to treat driving fear. Further research with randomized controlled trials is needed to verify efficacy. Moreover, simulators with lower configuration stages should be tested for a broad availability in psychotherapy.