Research related to uncertainty communication remains contradictory, with some authors providing arguments of why it should be communicated, whereas others arguing that we should not do so. Practically, though, the decision on whether or not to openly communicate uncertainties remains on the level of experts of a certain field. That is why, in this article we analyze the psychophysiological reaction of experts when exposed to uncertainty as well as their willingness to participate in decision-making procedures about nuclear decommissioning (a salient issue, in which many uncertainties prevail) and using a sample of N = 134 participants which are employees of nuclear-related institutions in Belgium (divided in 2 groups: familiar and unfamiliar with decommissioning). By using the Uncertainty Reduction Theory (URT) and Uncertainty Management Theory (UMT), we study for the first time (1) whether communicating uncertainty influences participation intention directly and (2) whether this impact is mediated by emotional arousal. The method consists of an experimental design, combining a survey with psychophysiological measurement of emotional arousal. Results show that participation intention is directly influenced by attitudes toward participation, moral norm and time constraints, whereas familiarity with the topic of decommissioning influences participation intention indirectly, through attitude toward participation. Uncertainty communication, our main variable of interest, does not influence participation intention. It does influence, though, emotional arousal (concerning the public acceptance of the remaining radioactivity resulting from decommissioning), but it does not generate negative feelings such as anger or fear. Given that in the literature there is a debate on whether or not uncertainties should be communicated, the findings of this study imply that the concern that uncertainty communication leads to negative feelings should not be used as a reason not to communicate uncertainty anymore. Further implications and limitations are discussed in the article.