Social steerability modulates perceptual biases

Abstract Verbal hints can bias perceptual decision-making, even when the information they provide is false. Whether individuals may be more or less susceptible to such perceptual influences, however, remains unclear. We asked naive participants to indicate the dominant color in a series of stimuli, after giving them a false statement about which color would likely dominate. As anticipated, this statement biased participants’ perception of the dominant color, as shown by a correlated shift of their perceptual decisions, confidence judgments and response times. Crucially, this perceptual bias was more pronounced in participants with higher levels of susceptibility to social influence, as measured by a standard suggestibility scale. Together, these results indicate that even without much apparatus, simple verbal hints can affect our perceptual reality, and that social steerability can determine how much they do so. Susceptibility to suggestion might thus be considered an integral part of perceptual processing. Statement of relevance At a time when fake news soar, understanding the role that simple verbal descriptions play in how we perceive the world around us is paramount. Extensive research has shown that perception is permeable to well-orchestrated manipulation. Comparatively less attention has been paid to the perceptual impact of false information when the latter is imparted simply and straightforwardly, through short verbal hints and instructions. Here we show that even a single sentence suffices to bias perceptual decision-making, and that critically, this bias varies across individuals as a function of susceptibility to social influence. Considering how here perception was biased by a single, plain sentence, we argue that researchers, communicators and policy-makers should pay careful attention to the role that social suggestibility plays in how we build our perceptual reality.