Social frame and tax compliance modulate electrophysiological and autonomic responses following tax-related decisions.

Given the intrinsic complexity of cognitive and affective processes affecting how people reason about taxes and their decisions to be compliant with such social duty, we aimed at exploring those latent processes by combining the analysis of their central and peripheral physiological correlates. We asked participants to make realistic economic decisions concerning tax-payment and manipulated the social vs. individual decisional frame. In addition, we took into account the potential role of tax-compliance trait. Thirty self-employed professionals took part in the study and completed a public good game while their autonomic (skin conductance - SC - and heart rate - HR) and neural brain (electroencephalography - EEG) activities were recorded. The analysis of physiological responses during the feedback phase - where participants could be presented or not with a fiscal audit - highlighted: (i) increased tonic SC levels and theta activity in the social condition than in the individual one; (ii) increased HR values when a fiscal audit did not take place, especially in participants who presented an enforced tax-compliance trait. Present findings support the idea that classic economic theories of tax behaviour developed under the assumption that taxpayers act as rational and individualist agents do not provide a comprehensive account for the decision-making process. They add to available evidence highlighting the contribution of psychological and social-affective variables to individuals' decision-making processes to pay or evade taxes and to their appraisal of the consequences of such choice, as suggested by the 'slippery slope' framework.