Reward mechanisms and artefacts fruition: neurophysiological and personality components

Artefacts appreciation, including artworks as well as handicraft and industrial products, involves the audience by an emotional point of view, guides motivational level and affects decision making. Moreover, it is well known that individual differences based on personality correlates play a key role in determining evaluation, preference and subjective responsiveness to specific features of a good. Emerging evidence suggests that these behaviors could rely on reward mechanisms, according to the approach-withdrawal motivational model of emotion, and that the left prefrontal brain activity may reflect the strength of the reward-related behavioral activation system (BAS and BAS-reward). Although it has been demonstrated that the DLPFC is a key structure in processing rewarding information, little is known about the relationship between neurophysiological and personality correlates supporting artefact appreciation and preference. Therefore, the present study aimed to explore the impact of reward mechanisms and their prefrontal correlates to support cognitive and emotive processes during the presentation of different artefacts (videos). Inhibitory rTMS (1 Hz) was applied on DLPFC to 24 participants, while electrocortical activity (EEG) and behavioral self-report evaluation were recorded. Two control conditions were included in the experimental design to control the simple stimulation effect (sham condition with absence of TMS stimulation) and the localization effect (control site condition, F3/F4 stimulation). Results showed that, in comparison to sham and control condition, F3 low-frequency stimulation (inhibitory effect) induced increased prefrontal alpha activity (brain activity reduction) during the processing of emotionally involving videos, suggesting a decreased interest due to the deactivation of reward-related mechanisms. In addition, theta activity was modulated by BAS-reward component. In conclusion, this study supported the prefrontal approach-withdrawal motivational model of emotion applied to artefacts processing, and suggested that some goods may elicit a stronger subjective response in terms of rewarding-power, resulting in a greater modulation of the prefrontal system. These results were revealed in both electrocortical responses and explicit subjective evaluation, and were supported by personality attitudes.