Stimulating the Right Temporoparietal Junction with tDCS Decreases Deception in Moral Hypocrisy and Unfairness

Abstract

Self-centered and other-regarding concerns play important roles in decisions of deception. To investigate how these two motivations affect deception in fairness related moral hypocrisy, we modulated the brain activity in the right temporoparietal junction (rTPJ), the key region for decision making involved in self-centered and other-regarding concerns. After receiving brain stimulation with transcranial direct current stimulation (tDCS), participants finished a modified dictator game. In the game, they played as proposers to make allocations between themselves and recipients and had a chance to deceive by misreporting their totals for allocations. Results show that deception in moral hypocrisy was decreased after anodal stimulation than sham and cathodal stimulation, only when participants know that their reported totals (appearing fair) would be revealed to recipients rather than being unrevealed. Anodal stimulation also increased offers to recipients than cathodal stimulation regardless of the revelation of reported totals. These findings suggest that enhancing the activity of rTPJ decreased deception caused by impression management rather than self-deception in moral hypocrisy and unfairness through facilitating other-regarding concerns and weakening non-material self-centered motivations. They provide causal evidence for the role of rTPJ in both other-regarding concerns and non-material self-centered motivations, shedding light on the way to decrease moral hypocrisy.

The Neural Mechanism of the Social Framing Effect: Evidence from fMRI and tDCS Studies

“…Consequently, behavioral preference varied as a function of the sensitivity to physical pain of the victim across conditions. While follow-up research is needed to determine which interpretation is more appropriate, both of them are in line with the finding that activating the rTPJ decreases antisocial behavior (e.g., deception) (see Tang et al, 2017).…”

“…Both electrodes were positioned firmly on the scalp with a plastic headband. The electrode montage and tDCS parameters were identical to those that successfully modulated cortical excitability of the rTPJ in previous studies (Jurcak et al, 2007;Santiesteban et al, 2012;Tang et al, 2017).…”

The Effect of High-Definition Transcranial Direct Current Stimulation of the Right Inferior Frontal Gyrus on Empathy in Healthy Individuals

“…Under the active HD-tDCS condition, a relatively weak current (1.5 mA) was delivered for 20 min. For sham stimulation, a 1.5 mA current stimulus was delivered and lasted only 30 s consistent with previous research (Civai et al, 2015 ; Mai et al, 2016 ; Tang et al, 2017 ). For all three stimulation conditions, the stimulation commenced with the delivery of a current that slowly increased from 0 mA to 1.5 mA (ramp-up duration of 15 s) and that slowly dropped from 1.5 mA to 0 mA at the end of the stimulation (ramp-down duration of 15 s; Cerruti and Schlaug, 2008 ; Holland et al, 2011 ).…”

Are Proselfs More Deceptive and Hypocritical? Social Image Concerns in Appearing Fair

“…These findings also provide implications for decreasing deception in moral hypocrisy. As previous studies show, great fraction of people show moral hypocrisy [i.e., 90% in Baston et.al.’s Study 2 (C. Daniel Batson et al, 1997 ), 100% in Lönnqvist et al’s Study 1 ( Lönnqvist et al, 2014 ), about 90% in our previous study ( Tang et al, 2017 )]. However, research about how to decrease it is still at the early stage.…”

“…Although increasing the concerns of self-image could decrease moral hypocrisy (C Daniel Batson et al, 1999 ; Lönnqvist et al, 2014 ), self-deception was found to be hardly diminished and quickly recovered even after repeatedly presenting the reality to people ( Chance et al, 2015 ). Our previous study found that facilitating prosocial motives could effectively decrease deception in moral hypocrisy ( Tang et al, 2017 ). Results in the current study support this finding by showing that prosocials were less deceptive and hypocritical than proselfs.…”