The Effect of Gender on Dorsolateral Prefrontal Cortex Transcranial DC Stimulation-Induced Disruption of Moral Judgment

There is a growing interest to understand the neural underlying mechanisms of moral judgment. Some evidence suggests that various areas of Prefrontal Cortex (PFC) such as right Dorsolateral PFC (DLPFC) might be involved in moral judgment and that these areas can play an important role in cognitive control processes of utilitarian/nonutilitarian choices. Non-invasive brain stimulation techniques such transcranial Direct Current Stimulation (tDCS) have opened new windows to explore the neural substrates of those cognitive functions. The possible regulatory effect of DLPFC on moral judgment elicited by personal (low conflict/high conflict) and impersonal moral delimmas has been investigated using tDCS. Two groups of university students (n=60, female=30) were enrolled in the current investigation. Two parallel moral judgment tasks were randomly presented to subjects when DLPFC was being stimulated (right anode/ left cathode or right cathode/left anode) or subjects were receiving sham tDCS. Each task series comprised personal, impersonal and non-moral dilemmas. Repeated measure analysis of variance indicated a significant interaction between dilemmas× gender × montage (F(116.699,2.084)= 4.346, P=0.014). Based on the results, while DLPFCtDCS induced different effects on moral judgment between two sexes, the differences between two types of stimulation were insignificant. This study extends the results of the previous investigations using anon-invasive brain stimulation technique to modulate utilitarian moral judgment with the effects being greater in women as compared tomen. Current insights support the notion that the effects of tDCS on moral utilitarianism (judgment) might be related to emotional integration of moral information conducted by the right DLPFC. Taken together, one may conclude that the disruption of DLPFC may influence moral utilitarianism possibly through modulating emotional cues rather than cognitive control of moral information alone in the face ofhigh conflict delimmas.