The study, from Neuro-Insight, involved investigating the subconscious associations that voters make between key words typically used in the referendum campaign, as well as the logos for the two official campaigns: Britain Stronger in Europe and Vote Leave. It featured over 100 participants aged 18-65; a mix of people intending to vote to leave, to vote to remain, and undecided voters. 

The findings suggested that there are significant drawbacks to this reliance on negative messaging. It claims that this association of risk with the ‘remain’ side, as opposed to its intended target of the Vote Leave campaign, could be especially detrimental. 

The Vote Leave campaign was found to have weaker links with ‘fearmongering’ and stronger links with ‘informative’ (though this was not true of voters who had already decided to vote ‘in'). 

“The rationale behind this study is that our brains work by association," said Heather Andrew, CEO of Neuro-Insight. "If we hear a word or see an image, our existing associations with that word or image mean that our brains are already cued to have certain expectations of what might come next.

"Our study shows that while the Britain Stronger In Europe campaign has been successful in getting ‘risk’ across to voters, ironically there is a danger that at a subconscious level ‘risk’ is associated with the ‘In’ campaign, rather than with the ‘Vote Leave’ campaign – the intended target.

"Given the likely number of undecided voters, the ‘In’ campaign may want to think about the subconscious impact of any messaging that focuses heavily on ‘risk'.”