Neural evidence for moral intuition and the temporal dynamics of interactions between emotional processes and moral cognition

Abstract

Behavioral and neurological studies have revealed that emotions influence moral cognition. Although moral stimuli are emotionally charged, the time course of interactions between emotions and moral judgments remains unknown. In the present study, we investigated the temporal dynamics of the interaction between emotional processes and moral cognition. The results revealed that when making moral judgments, the time course of the event-related potential (ERP) waveform was significantly different between high emotional arousal and low emotional arousal contexts. Different stages of processing were distinguished, showing distinctive interactions between emotional processes and moral reasoning. The precise time course of moral intuition and moral reasoning sheds new light on theoretical models of moral psychology. Specifically, the N1 component (interpreted as representing moral intuition) did not appear to be influenced by emotional arousal. However, the N2 component and late positive potential were strongly affected by emotional arousal; the slow wave was influenced by both emotional arousal and morality, suggesting distinct moral processing at different emotional arousal levels.

Colours’ Impact on Morality: Evidence from Event-related Potentials

“…This ERP effect was consistent with the behavioural findings that the reaction time differences between moral and immoral words only reached significance when the words were green rather than other colours. Previous studies have suggested that LPC is related to mental resource distribution41 and have considered it a representation of slow but controlled and elaborative processes, such as moral evaluation and reasoning313642. The larger LPC differences in green words in the present study showed that the conflict between immoral words and the metaphorical meanings of the colour green might lead people to devote more cognitive resources to completing moral evaluations and reasoning processes in late time windows.…”

“…Recently, neuroscientists demonstrated that there are many factors involved in moral processes (such as emotion28293031, culture32, and individual dispositions33) and identified the complex neural mechanisms underlying these factors. However, the neural mechanism responsible for the metaphorical connection between colours and moral concepts remains unknown.…”

“…A large body of ERP studies reported a late positive component (LPC) during a late time window from 300 to 800 ms post-stimulus. This component was related to mental resource distribution41 and was found to reflect controlled and elaborative processes, such as moral evaluation and reasoning3142.…”

“…As N300 may be related to the semantic integration of visual features40, we expected a significant influence of colour on moral judgement during the time window of N300. Given that LPC may reflect the elaborative processing and moral reasoning in late time windows3142, we predicted that the interaction between colours and morality would be significant for the LPC amplitude, which would reveal the specific distinctions of morality in different colours.…”

The time-course of moral perception: An electroencephalography investigation

“…In such studies, participants were recorded while processing morality-related words (e.g., Yang, Luo, & Zhang, 2017), behaviors (e.g., Yang, Li, Xiao, Zhang, & Tian, 2014), and images (e.g., Decety & Cacioppo, 2012), often in direct comparison to core disgust-related stimuli (e.g., Yang et al, 2014Yang et al, , 2017. Taken together, the extant ERP literature on morality is somewhat mixed: across this work, various researchers have observed morality-related changes in amplitudes in the N1 (Gui, Gan, & Liu, 2016;Yoder & Decety, 2014), N180 (successful versus attempted harm/help; Gan et al, 2016), recognition potential (versus neutral words; Yang et al, 2017), P200 (shame versus guilt; Zhu et al, 2019); P300 (versus neutral behaviors; Yang et al, 2014), N400 (versus neutral words; Luo et al, 2013), and late positive potential (LPP; Gui et al, 2016;Leuthold, Kunkle, Mackenzie, & Filik, 2015).…”