S18-2. Agency and responsibility

Abstract

Agency refers to the feeling that one’s voluntary actions caused external events, and is a source of human volition and responsibility. Past studies using Libet clock method showed that compression of the subjective temporal interval between actions and external events, called intentional binding, is closely linked to agency. Current theories postulate that the experience of agency is constructed via predictive and postdictive pathways. Here, one remaining problem is the source of human causality bias; people usually make misjudgments on the causality of voluntary actions and external events depending on rewarding or punishing outcomes. Furthermore, healthy subjects and depressive patients demonstrate different direction in causal attribution. This human causality bias is often problematic, since it can distort our responsibility for actions. To attend this issue, we investigated agency for rewarding and punishing outcomes following voluntary action in healthy subjects and depressive patients using intentional binding paradigm. Our results showed that healthy subjects show posdictive modulation of intentional binding in a consistent manner with self-serving bias. In contrast, depressive patients did not show such modulation of binding. Our study not only provides evidence for postdictive modification of agency, but also proposes a possible mechanism of human responsibility for actions.