Fig 1.
Overview of the experimental design and procedures.
The vicarious fear conditioning paradigm consisted of a learning stage, in which the participant watched videos of a demonstrator receiving electric shocks paired with a predictive visual cue, followed by a test stage, in which an increased skin conductance response (SCR) to the cue compared to a control stimulus, in the absence of the demonstrator, indexed vicarious fear learning. Each participant completed this paradigm under two different hypnotic suggestions, which were administered before each learning stage to induce high or low affect sharing with the demonstrator (order counterbalanced across participants). Each suggestion was revoked (so-called “cancellation”) after the learning stage to bring the participants back to their habitual level of affect sharing before the start of the test stage. Eye tracking was used to assess eye gaze during the learning stages. The demonstrators’ heads have been masked in this Figure to protect their identity; participants saw their full face and expressions.
Fig 2.
Effects of hypnotic suggestions for high versus low affect sharing on skin conductance response (SCR) in the learning (A, B) and test stage (C) and on tonic skin conductance level (SCL) across both stages (D), expressed as z-scores. A) SCR to seeing the colored square (CS+ or CS-) in the learning stage. B) SCR to seeing the demonstrator receive shocks (US) or no shocks (US absence) in the learning stage. The difference in responses to US and US absence indicates the unconditioned response. C) SCR to seeing the colored square (CS+ or CS-) in the test stage. The difference in responses to CS+ and CS- indicates the conditioned response. D) Tonic skin conductance level (SCL) observed in the learning and test stage. Error bars reflect 95% confidence intervals corrected for within-subject designs (see Methods). Results of individual participants are shown laterally as semi-transparent dots.
Fig 3.
Effects of hypnotic suggestions for high versus low affect sharing on skin conductance response (SCR) (panel A, B, C) and tonic skin conductance level (SCL) (panel D), shown separately for the two groups receiving the high affect sharing condition in round 1 (group 1) or in round 2 (group 2). The thick vertical arrows (“Round 1”) indicate which suggestion was delivered first in this group. Results are expressed as z-scores. A) SCR to seeing the colored square (CS+ or CS-) in the learning stage. B) SCR to seeing the demonstrator receive shocks (US+) or no shocks (No US+) in the learning stage. C) SCR to seeing the colored square (CS+ or CS-) in the test stage. D) Tonic SCL in the learning and test stage. Error bars reflect 95% confidence intervals corrected for within-subject designs (see Methods). Results of individual participants are shown laterally as semi-transparent dots.
Fig 4.
Results of the post-hypnosis interview showing the effects of hypnotic suggestions for high / low affect sharing on ratings of affect sharing, emotion recognition and declarative memory of the contingency between CS (colored square) and US (shock / no shock to demonstrator).
a) Participants rated how unpleasant the shocks were for the demonstrator in the video (emotion recognition–blue / dark lines) and how unpleasant it was for themselves to watch the shocks being delivered to the demonstrator (affect sharing–red / bright lines). b) Participants indicated how many shocks the demonstrator had received following the CS+ and CS-, respectively. Error bars reflect 95% confidence intervals corrected for within-subject designs (see Methods). CS–conditioned stimulus; US–unconditioned stimulus. Results of individual participants are shown laterally as semi-transparent dots.
Fig 5.
Eye tracking results of the learning stage.
Average fixation times at the cue (CS) and face area of interest, expressed as % of total fixation time, recorded during the presentation of (a) the CS and (b) the US are shown separately for the high / low affect sharing condition. Error bars reflect 95% confidence intervals corrected for within-subject designs. Results of individual participants are shown laterally as semi-transparent dots.
Table 1.
Spearman correlations among the differences in SCL, SCR and eye gaze observed between hypnotically induced high and low affect sharing in N = 36 participants (controlling for order).