Figure 4
Schemata of the behavioural paradigms employed in the main experiments. (A) Behavioural paradigm. After a general instruction on the first day, we measured the participants’ heat pain thresholds, then performed a stimulus calibration to allow for an experimental temperature that elicited pain sensitivity ratings of 60 to 65 on a visual analogue scale (VAS; 0–100) and used that temperature for 20 consecutive pain stimuli. The participants were asked to rate their pain experience after each pain stimulus. On the second day, heat pain threshold measures and pain sensitivity ratings (same temperature as on day 1) were assessed anew. Note that no expectancy manipulation took place here, because only participants in the Control group were tested in this basic design. (B) fMRI paradigm. Participants were positioned in the MRI scanner prior to the heat pain threshold measurements on both days to assure a similar experimental environment for all pain measures obtained. However, functional imaging measurements were only acquired for the pain sensitivity ratings (20 consecutive pain stimuli). Note that all participants in the fMRI experiment received a gender-related expectancy manipulation at the beginning of the second day, as all participants were either part of the MLPS or the FLPS group. (C) Cortisol paradigm (for physiological results, see Supplementary Results I). At six time points over the two experimental days (three time points per day, T1–T3), saliva samples were taken for subsequent cortisol concentration analysis. Additionally, to elicit stronger cortisol responses, a Cold Pressor Test (CPT) was added at the end of the second experimental day.
