Cognitive Mechanism Of Influence Of Self-relevance On Moral Decision-making:Effects Of Risk Level And Empathy

Moral decision-making is the process to choose an optimal course of action from multiple alternatives within a system of norms and values that guide our behavior within a community.It usually involves a trade-off between maintaining personal benefits and preventing harm to others,and which can elicit strong cognitive conflicts and emotional responses.Based on previous studies,the behavioral and neural responses during moral decision-making would vary with the different degrees of association between decision maker and receivers(i.e.,self-relevance).On the basis of reviewing and summarizing the relevant research,the present study aimed to combine with behavioral measures,subjective reports and event-related potential technology,through six ERPs experiments to investigate influence of self-relevance on moral decision-making,the roles of external decision risk and internal empathy ability during moral decision-making,as well as the variation and neural mechanism of moral decision-making under helpful and harmful contexts.Experiment 1 adopted the dilemma scenario-priming paradigm to examine the time course of the different intimate self-relevance impacts on the emotional and cognitive processes during moral decision-making.Results showed that participants made less altruistic decisions with increased decision times and experienced more unpleasant for strangers versus friends and acquaintances,which showing an obvious'egoistic tendency'.Moreover,at the early moral intuitional process,there was no significance difference observed at N1 under different intimate IR;however,at the emotional process,larger P260 which reflects the dilemma conflicts and negative emotional responses,was elicited when moral decision-making for strangers;at the later cognitive process,such difference was also observed at LPP(300-450 ms)which indexes the later top-down cognitive appraisal and reasoning processes.However,such differences were not observed between friends and acquaintances.Experiment 2 utilized a seminal moral decision task to investigate behavioral responses and neural processes during moral decision involving with different self-relevance.Event-related potentials were measured while participants were instructed to trade-off different amounts of money gains for themselves against different numbers of painful electric shocks experienced by the receivers(self,friend,or stranger).When making decisions about whether to shock others to gain money for themselves,participants were altruistic to forego more their self-interests to restrain harm directed to others than themselves.The early frontal Nl,indexing fast and automatic moral intuitional process was increased along with increased both intensities of painful electric shocks and amounts of money gains.Low self-relevance enhanced the intensity of moral conflict and aversive experience and added the subsequent mental cost of resolving this conflict,reflected by a larger P260-LPP(350 ms)effect in the harmful decisions toward strangers.Experiment 3 adopted the same dilemma scenario-priming paradigm,in which the level of decision risk was firstly presented,and then participants were asked moral decision-making task,to explore the modulation of decision risk on moral decision involving with different intimate self-relevance.Results indicated that proportions of helping were larger under the high level of decision risk than that under the low level of decision risk,as well as the slower speed of decision making.The proportions of helping friends were higher than that of helping acquaintances,as well as that of helping acquaintance higher than that of helping strangers,which showing an obvious'egoistic tendency'.Moreover,compared with friends and strangers,moral decisions toward acquaintances took longer times,and elicited larger P260 and LPP(300-450 ms),which suggesting an interesting 'acquaintance effect'.However,such effect in decision times and neural responses was eliminated under high level of decision risk.Experiment 4 adopted the same 'shock-gain' task to investigate the interaction between self-relevance and decision risk on the behavioral and neural responses during moral decision.Results showed that proportions of shocking were larger under the high level of decision risk than that under the low level of decision risk,as well as the slower speed of decision making.The proportions of shocking friends were higher than that of helping acquaintances,as well as that of shocking acquaintance higher than that of shocking strangers,which showing a similar 'egoistic tendency'.Moreover,compared with friends and strangers,moral decisions toward acquaintances took longer times,and elicited larger P260 and LPP(300-450 ms),which suggesting a similar 'acquaintance effect'.However,such effect in decision times and neural responses was eliminated under high level of decision risk.Experiment 5 sequentially adopted the same dilemma scenario-priming paradigm,to uncover the modulation of empathy ability on moral decision involving with both different intimate self-relevance and different levels of decision risk under the helpful situations.Results indicated that individuals with high empathy ability made more helping choices compare to individuals with low empathy ability.Moreover,individuals with low empathy ability made similar egoistic helping choices under the low levels of decision risk,and appeared similar 'acquaintance effect',and whereas these differences were disappeared under the high levels of decision risk.However,moral decision made by individuals with high empathy was not modulated by both self-relevance and decision risk under the helpful situation.Experiment 6 sequentially adopted the same 'shock-gain' task to uncover the modulation of empathy ability on moral decision involving with both different intimate self-relevance and different levels of decision risk under the harmful situations.Results indicated that individuals with high empathy ability made less shocking choices compare to individuals with low empathy ability.Moreover,individuals with low empathy ability made similar egoistic shocking choices under the low levels of decision risk,and appeared similar 'acquaintance effect',and whereas these differences were disappeared under the high levels of decision risk.However,moral decision made by individuals with high empathy was not modulated by both self-relevance and decision risk under the harmful situation.These results suggested that the higher the self-relevance in moral dilemmas is,the weaker the dilemma conflicts and emotional responses are,and the more efficient this conflicts are solved.External decision risk could suppress the egoistic moral selections through reputation mechanism,and decreased intensities of both emotional response and cognitive conflict evoked by different degree of both self-relevance and decision risk,which appearing at the early emotional and later cognitive process of moral decision-making.The behavioral responses,subjective reports and neural representations of moral decision making were significant different between high and low empathy ability individuals.Compared to individuals with low empathy ability,individuals with high empathy ability made less egoistic moral choices,and consumed less emotional and cognitive costs to solve moral conflicts.However,individuals with low empathy ability allocated more emotional and cognitive costs to solve this conflicts under moral decision-making toward acquaintances,and which was modulated by external decision risk.Taken together,moral decision-making under helpful and harmful situations would vary with different social situations,and'situational model of moral decision-making' can help clarify the interactions and internal mechanisms between various factors.