196 were used to induce moderate pain and median temperatures rated as NRS 6 to 8 were used to induce high pain. Baseline, acquisition, and evocation phases During baseline, 2 moderate and 6 high pain trials were administered on both arms, with an ISI of 5 seconds. During acquisition, 16 nocebo and 16 control stimuli were administered in alternating order. During evocation, 8 nocebo and 8 control stimuli were administered in alternating order. During nocebo acquisition and evocation, the ISI was 10 seconds. In all phases the thermode was moved to a more proximal site on the arm after each pain trial, in order to avoid habituation or sensitization to heat-pain. Nocebo manipulation A commercial moisturizing gel that was given the name “Trans-Dermal Aspartate” or “TDA” was used as the nocebo treatment in the procedure; participants were told it was a capsaicin gel used on the skin for research purposes only. Half of the participants received the gel from a blue jar and the other half from a brown jar, both featuring sham pharmaceutical labels. Negative suggestions were used to create expectations regarding the pain enhancing effects of the gel. Participants were told that the gel is a capsaicin-based gel that is known for its painincreasing properties. Participants’ arms were marked with medical tape to create four 3x3 cm thermode-placement sites on both arms. Prior to the start of the acquisition phase, the gel was rubbed into the two nocebo sites (the first and third most proximal sites on the right arm). Messages displayed on a computer screen via E-Prime 2.0 (Psychology Software
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