How Trust in Science Shapes Belief Updating in Individuals Exposed to Scientific Evidence: A Psychological Perspective

In previous studies, Rosman and Grösser (2024) showed that individuals with high trust in science are more likely to update their beliefs on a certain topic if they are confronted with scientific information on that topic. While this effect itself is intuitively plausible, the psychological mechanisms behind it are still unclear. The present study aims to investigate two things: First, it will test whether individuals with high trust in science are more likely to update their beliefs when the evidence in question comes from a reputable source (i.e., higher author expertise), which would suggest that second-hand evaluations (i.e., source evaluations) play an important role in this effect. Second, it investigates whether cognitive dissonance drives belief updating in individuals with high trust in science. I assume that individuals with high trust in science are more likely to experience cognitive dissonance when presented with scientific evidence that contradicts their prior beliefs. This is because high trust in science makes it harder to dismiss or devalue science-based information. As a result, such dissonance may influence how these individuals update their beliefs. Furthermore, I expect that this potential effect of dissonance is particularly pronounced when the evidence comes from a reputable scientific source, compared to a source with low scientific expertise. In the present study, I will test these assumptions by deliberately exposing participants to scientific evidence (in the form of short study descriptions) on the effects of acupuncture in the treatment of back pain. The evidence will be experimentally manipulated with regard to the expertise of the alleged study author (in terms of author descriptions which precede the study descriptions), and with regard to the direction of the evidence (studies speaking for the efficacy of acupuncture vs. unclear / diverging evidence). Consequently, a 2x2 design (author expertise: high vs. low, evidence direction: pro acupuncture vs. diverging evidence) will be employed; acupuncture-related beliefs will be measured pre-post.