PUB - Publikationen an der Universität Bielefeld

As people are social beings, they are inclined to infer the emotions and intentions of their counterpart in order to adapt their behavior. This capacity, which is often referred to as forming a cognitive and emotional theory of mind (ToM), can consolidate social relations and also helps protecting people’s well-being. In this process, body language, such as facial expressions and gestures, is an important source of information, in particular, since it develops beyond voluntary control. Based on current research, this dissertation aimed at exploring the brain activation patterns related to different aspects of nonverbal body language used as a source of empathic evaluation such as dynamics, ambiguity, subjective relevance and accessibility to conscious evaluation. Based on reports of a ToM deficit associated with older age, empathic reasoning based on affective states seen in photographs was compared in young and old adults. Taken together, our experiments highlight the role of the inferior frontal cortex, the adjacent anterior insula cortex and the dorsomedial frontal cortex in empathic evaluation based on facial expressions and gestures. Brain areas associated with the putative human mirror neuron system were recruited regardless whether the seen emotional expression was ambiguous due to its dynamics or its low degree of emotional expressiveness, not consciously accessible or of varying degree of social impact. Within correspondence to previous research on emotional contagion, empathy and ToM, this finding highlights the relevance of perception-action-coupling in social life. In addition, parts of the DMFC became activated either with or without an explicit instruction to empathize. The DMFC has been implicated in affective ToM, primarily with a self-referential component. Areas in the DMFC, as well as parts of the hMNS were shown to be recruited in young, as well as in old adults but at different time points. In contrast to the young adults who accurately inferred the origin of an emotional state seen in a face, the old adults’ deficit in efficiently forming a ToM was related to a too early engagement of anterior prefrontal higher order control areas. This was likely to bind cognitive resources due to upregulation of other top-down modulated ToM associated areas at a time point when not all relevant information for efficient reasoning was available. Finally, we consistently found activation within the DLFC supporting the notion that it is not only crucially involved in social decision-making but that there is some degree of functional specialization within this large frontal area. While activation in posterior parts of the DLFC became activated during the preparatory stage of the decision when some but not all decision-relevant information were present, the actual decision was reflected by activation of a more anterior portion of the DLFC being interconnected with premotor, and dorsomedial frontal areas.