Does Choice Matter? Exploring Generalisation of Socially Induced Nocebo Effects and the Potential of Choice as an Intervention

Abstract

The nocebo effect is a powerful psychobiological phenomenon, where negative expectancies exacerbate symptoms unattributable to any active component of an intervention. Social modelling has been proposed as a strong predictor of nocebo effects. However, research has yet to explore whether social information concerning similar, but not identical, treatments facilitate the nocebo effect. This study employed a Virtual Reality (VR) model to investigate strength of nocebo cybersickness when a social model described symptoms resulting either from an identical, or similar, VR experience. Choice was explored as a potential intervention to attenuate any socially-induced nocebo effects. Prior to their own VR experience, 134 participants were quasi-randomised to a social modelling condition: Social Modelling Consistent (social model reports cybersickness during the same VR activity subsequently undergone by the participant); Social Modelling Inconsistent (model undertakes a different VR activity); No Social Modelling (Control). All participants were further assigned to a choice condition: Choice (participants choose their VR environment); No Choice (participants assigned). A social modelling effect was found; cybersickness was significantly greater in the groups that viewed the social model prior to their experience. Cybersickness was also significantly exacerbated in the ‘Inconsistent’, compared to ‘Consistent’, social modelling groups. Choice significantly mitigated the social modelling effect, but only in the Inconsistent group, suggesting the effect of choice depends on the social information communicated. Social modelling increased expectancy and state anxiety and these measures were significantly correlated with increased cybersickness. However, choice had no effect on sense of control or affect, despite being theoretically linked. These findings demonstrate that socially modelled nocebo effects can generalise across contexts, and that choice can mitigate this effect. However, further research is required to unravel the mechanisms driving group differences.