The sense of agency and the attribution of responsibility in human behavior

Abstract

The sense of agency refers to subjective experience of controlling external environment through voluntary actions. When individuals interact with the outside world through their behaviors, the feeling of "I am the initiator of this action" may induce a self-attributed responsibility. Moreover, a sense of agency may allow individuals to choose between different options by predicting their consequences. Therefore, the ability to control one's own behavior can be used as an index for responsibility attribution in moral and legal fields. Here, we review the factors influencing sense of agency and responsibility attribution. Some empirical studies highlight the intention of actions and the value of outcomes. The intention is a prerequisite for sense of agency and responsibility, and the characteristics of subsequent events affect how we perceive our behaviors. Other studies support the internal comparator model, which suggests that the match between prediction based on efferent copy of motor command and actual sensory feedback is the premise of sense of agency. In joint actions, the generation and level of sense of agency and responsibility are related to group identity, social status and other factors. When two individuals cooperate as equals in the management of an event, the new identity of "we" is a force that results in a sense of control over their partners' behavior. But participating as a follower in the teamwork, being in the presence of another agent (even if it has no causal effect on the outcome) will lead to a reduction in or disappearance of the sense of agency. The fundamental assumption of law is that individuals have the ability to control their own behaviors and are responsible for their actions and the consequences of those actions. Following this supposition, the factors that affect sense of agency can also have effect on the responsibility attribution. The level of sense of agency can be used to explain individuals' responsibility. For instance, people with abnormal agency, such as schizophrenia patients, can have their sentences pardoned or commuted. Therefore, disorders of brain activities could be taken into account by the court in sentencing. Neuroimaging studies have highlighted the role of fronto-parietal network, including pre-supplementary motor area (pre-SMA), posterior parietal cortex (PPC), temporo-parietal junction (TPJ), dorsolateral prefrontal cortex (DLPFC) and etc. One possible mechanism may be that the frontal cortex generates the action signals of selection, intent and initiation, while the parietal lobe, acting as a comparator model, monitors and compares these signals with the actual feedbacks. The TPJ and DLPFC play important roles in self-referential processing and the theory of mind task, and are also involved in the judgement of moral and criminal responsibility. Future investigations need to explore the activation patterns and functional connectivity of these brain regions under different levels of sense of agency and responsibility, to qualify and quantify the levels of individuals' control over their behaviors.