Participants
A total of 95 undergraduate students at the Erasmus university Rotterdam
were recruited in exchange for course credit. Based on previous
literature (Kastner et al., 2015; Stegmann et al., 2020; Talmi et al.,
2019), the smallest effect size we expected was for ssVEPs for the
comparison between CS+ and CS-. We used G*power 3.1.9.7 to calculate the
interaction between the two CSs and the three groups, with a small to
moderate effect size f = .20, alpha set at .05 and power at 85.
The power analysis indicated a total sample of 72 participants would be
sufficient, however we collected 95 to account for exclusions due to
technical problems. Seven participants were excluded (two from the High
Uncertainty and five from the Low Uncertainty group) due to technical
problems, resulting in a final sample of 88 (17 male, 1 non-binary) with
a mean age of 20.54 years (SD = 3.45). All participants had
normal or corrected-to-normal vision and no family history of photic
epilepsy. Participants were randomly assigned to one of the three
groups. The groups did not differ in age, sex ratio, depression, state
anxiety, or intolerance of uncertainty levels (see Table 1). However,
the LU group had higher levels of trait anxiety and social anxiety than
the MU group. The experimental procedure of the current study was
approved by the Ethical Committee of the Erasmus University Rotterdam in
accordance with the declaration of Helsinki. The study has been
registered in Open Science Framework
(https://osf.io/tdqj3/?view_only=fb8ca7beabb444d38aadd8a999249a44).