@article{RieplMusselOsinskyetal.2016, author = {Riepl, Korbinian and Mussel, Patrick and Osinsky, Roman and Hewig, Johannes}, title = {Influences of State and Trait Affect on Behavior, Feedback-Related Negativity, and P3b in the Ultimatum Game}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {11}, doi = {10.1371/journal.pone.0146358}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147386}, pages = {e0146358}, year = {2016}, abstract = {The present study investigates how different emotions can alter social bargaining behavior. An important paradigm to study social bargaining is the Ultimatum Game. There, a proposer gets a pot of money and has to offer part of it to a responder. If the responder accepts, both players get the money as proposed by the proposer. If he rejects, none of the players gets anything. Rational choice models would predict that responders accept all offers above 0. However, evidence shows that responders typically reject a large proportion of all unfair offers. We analyzed participants' behavior when they played the Ultimatum Game as responders and simultaneously collected electroencephalogram data in order to quantify the feedback-related negativity and P3b components. We induced state affect (momentarily emotions unrelated to the task) via short movie clips and measured trait affect (longer-lasting emotional dispositions) via questionnaires. State happiness led to increased acceptance rates of very unfair offers. Regarding neurophysiology, we found that unfair offers elicited larger feedback-related negativity amplitudes than fair offers. Additionally, an interaction of state and trait affect occurred: high trait negative affect (subsuming a variety of aversive mood states) led to increased feedback-related negativity amplitudes when participants were in an angry mood, but not if they currently experienced fear or happiness. We discuss that increased rumination might be responsible for this result, which might not occur, however, when people experience happiness or fear. Apart from that, we found that fair offers elicited larger P3b components than unfair offers, which might reflect increased pleasure in response to fair offers. Moreover, high trait negative affect was associated with decreased P3b amplitudes, potentially reflecting decreased motivation to engage in activities. We discuss implications of our results in the light of theories and research on depression and anxiety.}, language = {en} } @article{PeperkornDiemerAlpersetal.2016, author = {Peperkorn, Henrik M. and Diemer, Julia E. and Alpers, Georg W. and M{\"u}hlberger, Andreas}, title = {Representation of Patients' Hand Modulates Fear Reactions of Patients with Spider Phobia in Virtual Reality}, series = {frontiers in Psychology}, volume = {7}, journal = {frontiers in Psychology}, number = {268}, doi = {10.3389/fpsyg.2016.00268}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165307}, year = {2016}, abstract = {Embodiment (i.e., the involvement of a bodily representation) is thought to be relevant in emotional experiences. Virtual reality (VR) is a capable means of activating phobic fear in patients. The representation of the patient's body (e.g., the right hand) in VR enhances immersion and increases presence, but its effect on phobic fear is still unknown. We analyzed the influence of the presentation of the participant's hand in VR on presence and fear responses in 32 women with spider phobia and 32 matched controls. Participants sat in front of a table with an acrylic glass container within reaching distance. During the experiment this setup was concealed by a head-mounted display (HMD). The VR scenario presented via HMD showed the same setup, i.e., a table with an acrylic glass container. Participants were randomly assigned to one of two experimental groups. In one group, fear responses were triggered by fear-relevant visual input in VR (virtual spider in the virtual acrylic glass container), while information about a real but unseen neutral control animal (living snake in the acrylic glass container) was given. The second group received fear-relevant information of the real but unseen situation (living spider in the acrylic glass container), but visual input was kept neutral VR (virtual snake in the virtual acrylic glass container). Participants were instructed to touch the acrylic glass container with their right hand in 20 consecutive trials. Visibility of the hand was varied randomly in a within-subjects design. We found for all participants that visibility of the participant's hand increased presence independently of the fear trigger. However, in patients, the influence of the virtual hand on fear depended on the fear trigger. When fear was triggered perceptually, i.e., by a virtual spider, the virtual hand increased fear. When fear was triggered by information about a real spider, the virtual hand had no effect on fear. Our results shed light on the significance of different fear triggers (visual, conceptual) in interaction with body representations.}, language = {en} }