Early EEG responses to pre-electoral survey items reflect political attitudes and predict voting behavior

Giulia Galli,Stefan Bode,Viviana Betti,Giorgio Di Lorenzo,Lorenzo De Sio,Aldo Paparo,Davide Angelucci,Chiara De Giorgi

doi:10.1038/s41598-021-96193-y

Abstract

Self-reports are conventionally used to measure political preferences, yet individuals may be unable or unwilling to report their political attitudes. Here, in 69 participants we compared implicit and explicit methods of political attitude assessment and focused our investigation on populist attitudes. Ahead of the 2019 European Parliament election, we recorded electroencephalography (EEG) from future voters while they completed a survey that measured levels of agreement on different political issues. An Implicit Association Test (IAT) was administered at the end of the recording session. Neural signals differed as a function of future vote for a populist or mainstream party and of whether survey items expressed populist or non-populist views. The combination of EEG responses and self-reported preferences predicted electoral choice better than traditional socio-demographic and ideological variables, while IAT scores were not a significant predictor. These findings suggest that measurements of brain activity can refine the assessment of socio-political attitudes, even when those attitudes are not based on traditional ideological divides.

Highlights

Self-reports are conventionally used to measure political preferences, yet individuals may be unable or unwilling to report their political attitudes
The investigation of political attitudes using measurements of brain activity has gained popularity in recent years11–13. Functional Magnetic Resonance Imaging (fMRI) and EEG studies have revealed differences in brain structure and function depending on political preferences[12,13,14,15,16,17,18,19,36]
As the extant literature has mainly focused on the liberal-conservative political spectrum, it is unclear whether other political divides would be reflected in different patterns of brain activity

Summary

Introduction

Self-reports are conventionally used to measure political preferences, yet individuals may be unable or unwilling to report their political attitudes. The combination of EEG responses and self-reported preferences predicted electoral choice better than traditional socio-demographic and ideological variables, while IAT scores were not a significant predictor These findings suggest that measurements of brain activity can refine the assessment of socio-political attitudes, even when those attitudes are not based on traditional ideological divides. This component is traditionally considered an index of semantic incongruency[26], but several social neuroscience studies have demonstrated that this component is responsive to incongruencies with one’s moral values, stereotypes[27,28,29] and violations of social norms[30] Consistent with this functional interpretation, in our previous study we found that the N400 was larger for information that contradicted participants’ views on the EU, and its modulation predicted future referendum voting b ehavior[19]. In the current investigation, we used the N400 as an index of political preferences and as a brain-based predictor of voting behavior

Methods

Results

Conclusion