Study: NCT04197154

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Threat manipulation (control, no threat)
Description: Before the start of conditioning, a mock skin-sensitivity test informs participants that their skin reacts to heat normally and it is safe for them to participate. A skin-sensitivity reading shows participants a scale that is in the green (no danger) zone.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Threat manipulation (control, no threat)
Description: Before the start of conditioning, a mock skin-sensitivity test informs participants that their skin reacts to heat normally and it is safe for them to participate. A skin-sensitivity reading shows participants a scale that is in the green (no danger) zone.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Threat manipulation
Description: Before the start of conditioning, a mock skin-sensitivity test informs participants that their skin is very sensitive and their nerve fibers are very responsive and they may have adverse reactions to the heat-pain application. A skin-sensitivity reading shows participants a scale that is in the red (higher danger) zone.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Conditioning of moderate pain
Description: During nocebo trials of the acquisition phase, conditioned stimuli (i.e., on-screen visual cues ON signaling the activation of sham electrical stimulation) are paired to unconditioned moderate-pain stimuli, to induce a negative association between the activation of electrical stimuli and an increase in pain. During control trials of the acquisition phase, the deactivation of the sham electrical stimulation (i.e., on-screen message OFF) is paired to 'baseline' pain of lower intensity.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Conditioning of moderate pain
Description: During nocebo trials of the acquisition phase, conditioned stimuli (i.e., on-screen visual cues ON signaling the activation of sham electrical stimulation) are paired to unconditioned moderate-pain stimuli, to induce a negative association between the activation of electrical stimuli and an increase in pain. During control trials of the acquisition phase, the deactivation of the sham electrical stimulation (i.e., on-screen message OFF) is paired to 'baseline' pain of lower intensity.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Conditioning of high pain
Description: During nocebo trials of the acquisition phase, conditioned stimuli (i.e., on-screen visual cues ON signaling the activation of sham electrical stimulation) are paired to unconditioned high-pain stimuli, to induce a negative association between the activation of electrical stimuli and an increase in pain. During control trials of the acquisition phase, the deactivation of the sham electrical stimulation (i.e., on-screen message OFF) is paired to pain of lower intensity.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Extinction
Description: During extinction, the previously conditioned nocebo effects on pain are attenuated by pairing the nocebo and control visual cues (i.e., on-screen messages ON and OFF) to pain stimuli of only lower intensity.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Extinction
Description: During extinction, the previously conditioned nocebo effects on pain are attenuated by pairing the nocebo and control visual cues (i.e., on-screen messages ON and OFF) to pain stimuli of only lower intensity.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Extinction
Description: During extinction, the previously conditioned nocebo effects on pain are attenuated by pairing the nocebo and control visual cues (i.e., on-screen messages ON and OFF) to pain stimuli of only lower intensity.