Health complaints and wind turbines: The efficacy of explaining the nocebo response to reduce symptom reporting.

BACKGROUND A number of people are reporting an environmental sensitivity to sub-audible windfarm sound (infrasound), characterised by the experience of recurrent non-specific symptoms. A causal link between exposure and symptoms is not indicated by empirical evidence. Research indicates symptoms may be explained by the nocebo response, whereby health concerns and negative expectations, created from social discourse and media reports, trigger symptom reporting. OBJECTIVE The experimental aim was to test whether providing a nocebo explanation for symptoms, to individuals reporting symptomatic experiences during infrasound exposure, would ameliorate symptoms during further exposure. METHOD Sixty-six volunteers were randomly assigned to nocebo explanation or biological explanation groups. Participants were concurrently exposed to infrasound and audible windfarm sound, while reporting on current symptoms and mood, during two exposure sessions. Preceding session one, participants watched a presentation integrating media warnings about purported health risks posed by windfarm infrasound. Before session two, nocebo explanation participants viewed material outlining how nocebo responding could explain symptom reporting. Instead biological explanation participants watched material presenting pathophysiological theories for symptoms. RESULTS During session one, participants reported increased symptoms and mood deterioration from baseline assessment. During session two symptom reporting and mood deterioration was maintained by biological explanation participants, while mood and symptoms reported by nocebo explanation participants returned to baseline levels. CONCLUSION Results indicate that providing an explanation of the nocebo response, followed by exposure to infrasound, has the potential to operate as an intervention to reduce symptomatic experiences in people reporting symptoms attributed to windfarm generated infrasound.