Right or left wing? The electricity in your brain can show your preference
A new study published in Scientific Reports, a prestigious journal of the Nature group, shows how specific electrical activity in the brain can predict one's voting behaviour. The research is the result of the work of an interdisciplinary group of neuroscientists, psychologists and political scientists, a collaboration between researchers of Sapienza University of Rome and Giulia Galli of Kingston University London, first author of the study, in collaboration with Guido Carli Free International University of Social Sciences (LUISS), University of Rome 'Tor Vergata' and the University of Melbourne.
The study was carried out in the five weeks leading up to the 2019 European elections when the political debate was dominated by the contrast between populist and mainstream parties. Research participants took part in a pre-election survey with sentences expressing more or less populist positions about various issues, from immigration to the economy to the European Union. However, unlike a traditional pre-election poll, participants answered the survey while their brain activity was being recorded at the laboratory directed by Viviana Betti of the Department of Psychology at Sapienza University.
Authors used an electroencephalograph (EEG), an instrument that records electrical activity in the brain. In particular, the focus was on the N400, electrical activity that manifests as a wave produced by the brain whenever we are confronted with information that goes against our beliefs. In the week following the vote, all participants were contacted again and asked which party they had voted for. The researchers' expectation, later confirmed by the results, was that the participants' brains would respond with an N400 wave to any sentence that disagreed with their political beliefs and that the amplitude of the N400 wave would predict the vote.
Indeed, the results showed that the brain responded differently depending on the participants' political beliefs: the N400 wave manifested itself strongly to political disagreement, for example, in response to populist content in participants sympathetic to non-populist parties. Not only that. The amplitude of this brain response was able to predict, with a high level of accuracy, whether participants subsequently cast a populist vote or a vote for a mainstream party, with a predictive ability superior to classical vote predictors typically used in electoral predictions. A surprising finding was that the N400 brain signal was evident in response to phrases concerning economic issues, such as citizens’ basic income (also called universal basic income). In essence, the brain was activated differently for populist and non-populist content, but only when this content was related to economic issues rather than issues traditionally associated with populism, such as nationalism or aversion to the Establishment.
What do this study's results tell us? First of all, that the recording of brain activity, in addition to direct responses to surveys, increases the predictive power of surveys. It is not difficult to understand why, given that the so-called social desirability bias often influences responses to surveys of all kinds. In this sense, recording brain activity allows one to 'bypass' people's direct response and access more truthful opinions or attitudes.
Another potential benefit of brain activity recording concerns undecided voters. In an earlier study in 2016, conducted by one of the authors in the days leading up to the Brexit referendum, the brain responses of undecided voters were predictive of the subsequent 'Leave' or 'Remain' vote, proving that undecided voters may have 'embryonic' preferences, not yet conscious, which can nevertheless be detected through brain activity.
Traditional pre-election polling certainly has advantages over measuring brain activity, not least the ability to collect information from a large number of people at a reduced cost in less time. However, the results of this new study demonstrate how the use of neuroscientific methods allows for more accurate and detailed predictions. In the wake of neuroeconomics studies, which have shown how individual brain responses can predict collective choices, one can assume that this study is the first step towards 'neuroprediction' of electoral choices.
Early EEG responses to pre-electoral survey items reflect political attitudes and predict voting behavior - Giulia Galli, Davide Angelucci, Stefan Bode, Chiara De Giorgi, Lorenzo De Sio, Aldo Paparo, Giorgio Di Lorenzo & Viviana Betti - Scientific Report. DOI https://doi.org/10.1038/s41598-021-96193-y
Department of Psychology