Public facilities that have NIMBY (not in my backyard) structure involve both a social dilemma, in which individuals' decisions to prevent the worst outcomes for themselves undermine the public interest, and a moral dilemma focused on the majority versus the minority. This study examined the cognitive-neural processes in judging whether to prioritize the site residents or the citizenry as a whole within the context of NIMBY. Our ROIs were the right angular gyrus being related to concern about the worst possible outcomes for others and oneself, the amygdala associating with emotional aversion to prioritizing the majority, and the vmPFC, which integrates the aversion into "all things considered" judgments. As a result of comparing ingroup conditions for which a NIMBY facility may make participants worst-off position and outgroup conditions for which this possibility is denied, the right angular gyrus was activated in both conditions. The amygdala was activated only in the ingroup, and the vmPFC exhibited a stronger tendency in the ingroup. We concluded that the cognitive-neural processes in judgments on NIMBY facilities are common to both decision-making to avoid the worst-off position for others and for oneself and moral judgments between the majority and the minority.
Keywords: NIMBY; amygdala; right angular gyrus; vmPFC.