PT  - JOURNAL ARTICLE
AU  - Tibor M. Szikszay
AU  - Wacław M. Adamczyk
AU  - Janina Panskus
AU  - Lotte Heimes
AU  - Carolin David
AU  - Philip Gouverneur
AU  - Kerstin Luedtke
TI  - Psychological mechanisms of offset analgesia: The effect of expectancy manipulation
AID  - 10.1101/2022.08.09.503102
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.08.09.503102
4099  - http://biorxiv.org/content/early/2022/08/11/2022.08.09.503102.short
4100  - http://biorxiv.org/content/early/2022/08/11/2022.08.09.503102.full
AB  - A frequently used paradigm to quantify endogenous pain modulation is offset analgesia, which is defined as a disproportionate large reduction in pain following a small decrease in a heat stimulus. The aim of this study was to determine whether suggestion influences the magnitude of offset analgesia in healthy participants. A total of 97 participants were randomized into three groups (hypoalgesic group, hyperalgesic group, control group). All participants received four heat stimuli (two constant trials and two offset trials) to the ventral, non-dominant forearm while they were asked to rate their perceived pain using a computerized visual analogue scale. In addition, electrodermal activity was measured during each heat stimulus. Participants in both intervention groups were given a visual and verbal suggestion about the expected pain response in an hypoalgesic and hyperalgesic manner. The control group received no suggestion. In all groups, significant offset analgesia was provoked, indicated by reduced pain ratings (p < 0.001) and enhanced electrodermal activity level (p < 0.01). A significant group difference in the magnitude of offset analgesia was found between the three groups (F[2,94] = 4.81, p < 0.05). Participants in the hyperalgesic group perceived significantly more pain than the hypoalgesic group (p = 0.031) and the control group (p < 0.05). However, the electrodermal activity data did not replicate this trend (p > 0.05). The results of this study indicate that suggestion can be effective to reduce but not increase endogenous pain modulation quantified by offset analgesia in healthy participants.Competing Interest StatementThe authors have declared no competing interest.