Impact of treatment expectations on pain and pain empathy.
Conditions
Interventions
Group 1: Healthy volunteers and another (alleged) study participant alternately receive heat pain stimuli in three experimental conditions, which vary trial-by-trial (within-subject design).
Brief su
Sponsors
Universitätsklinikum Essen, Klinik für Neurologie
Eligibility
Sex/Gender
All
Age
18 Years to 80 Years
Inclusion criteria
Inclusion criteria: - Healthy - Fluent in German - Written voluntary consent to participate in this study - Abstain from alcohol 24 hours before each testing day - Normal or corrected-to-normal sight (glasses, contact lenses) - Normal hearing ability
Exclusion criteria
Exclusion criteria: - Active use of psychoactive substances 3 months prior to testing session Cannabis: required abstinence at least 3 months prior to testing session - Regular intake of medication in the last 7 days (except hormonal contraceptives or medications such as antihistamines or L-thyroxine) - Allergy medication intake the day of testing - Use of over-the-counter pain medication 72 hours before participation - Regular intake of over-the-counter pain medication (> 2 times per month) - Chronic or acute pain (headaches, backpain, radicular pain, neuropathic pain, unspecific pain indicating a pain disorder): No more than 2 occurrences per month - Other severe medical conditions (e.g., cardiovascular, respiratory, nervous, gastrointestinal, or metabolic diseases, etc.) - Acute, or history of, mental disorders (e.g. manifest depression, schizophrenia, substance use disorders). For Depression, Anxiety: minimum of one year post therapy, no remission - Allergies (e.g., contact allergies) - Skin diseases (e.g. atopic dermatitis), injuries (e.g. sunburn, scars), tattoos open wounds or inflammation/eczema of the skin at the site of stimulation. - Participation in an experimental study on empathy, or prosocial behavior - Participation in an experimental study including medication intake within the last 3 months - Current participation in other experimental/clinical studies at the time of testing - Color blindness or red-green color deficiency - Surgical procedures within the last 3 months, especially if not fully healed/currently painful - Impaired vision that cannot be corrected with contact lenses or glasses - Astigmatism that cannot be corrected with contact lenses or glasses - Consumption of alcohol the day of, or the day prior to testing - Acute infections - BMI 30
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Ratings of self-experienced and empathic pain associated with positive and negative expectations regarding pain during the conditioning and empathy sessions. Both sessions take place at the same day, the whole experiment takes approximately four hours. The following outcomes will be measured to test specific hypotheses: H1a: The conditioning procedure will lead to expectations of pain relief in the placebo condition and expectations of pain worsening in the nocebo condition, as compared to the control condition. • Treatment expectations (measured during the conditioning session): - Expectancy ratings ragerding the pain intensity of a stimulus after a green/yellow/red cross (“How painful do you expect the stimulation to be after the green/yellow/red cross?”, VAS-scale, 0 = not painful at all, 100 = unbearably painful) H1b: The conditioning procedure will lead to a decrease in pain intensity ratings in the placebo condition and an increase in pain intensity ratings in the nocebo condition, as compared to the control condition. • Self-experienced pain (measured during the conditioning session): - Pain intensity ratings ("How painful was this stimulation for you?", VAS-scale, 0 = not painful at all, 100 = unbearably painful) H2a: Subjective first-hand and empathic pain intensity ratings in the Empathy session will vary by condition, with a decrease in the placebo condition and increase in the nocebo condition, as compared to the control condition. • Self-experienced pain (measured during the empathy session): - Pain intensity ratings ("How painful was this stimulation for you?", VAS-scale, 0 = not painful at all, 100 = unbearably painful) • Pain empathy (measured during the empathy session): - Pain intensity ratings ("How painful was this stimulation for the other person?", VAS-scale, 0 = not painful at all, 100 = unbearably painful) H2b: Subjective empathic unpleasantness ratings in the Empathy session will vary by condition, with a decrease in the placebo co | — |
Secondary
| Measure | Time frame |
|---|---|
| Note that some of the secondary outcomes mentioned here are collected for the Collaborative Research Center. Those used for exploratory analyses in this study are marked with an asterisk (*). Extent of subjective placebo analgesia and nocebo hyperalgesia (difference in ratings of actual pain intensity between experimental and control conditions during the empathy session). * Questionnaires (Timepoints of administration can be taken from the short summary of the study procedure): T1: • Sociodemographics • Menstrual cycle (only for menstruating participants) • DSF – Acute Pain + Medication (Petzke et al., 2021) • Body Mindset Inventory (BMI; Zion, 2021) • Pain Catastrophizing Scale (PCS, Sullivan et al., 1995)* • Fear of Pain Questionnaire (FPQ-III, Flack et al., 2017)* • Perceived Stress Scale (PSS-10, Cohen et al., 1983) • Somatosensory Amplification Scale (SSAS, Barsky et al., 1990) • State-Trait-Anxiety-Depression Inventory (STADI trait; Renner et al., 2018)* • 10-item-Big-Five-Inventory (BFI-10, Rammstedt, 2007)* • Interoceptive Awareness and Sensitivity Questionnaire (ISAQ, Bogaerts et al., 2022) T2: • State-Trait-Anxiety-Depression Inventory (STADI state; Renner et al., 2018)* • Positive and Negative Affect Schedule (PANAS; Breyer & Bluemke, 2016; Watson et al., 1988)* • Generic Rating for Treatment Pre-Experiences, Treatment Expectations, and Treatment Effects (G-EEE) (expectation, before Conditioning session; Rief et al., 2021) T3: • G-EEE (current effects, after Conditioning session) • G-EEE (expectation, before Empathy session, block 1) • STADI state* T4: • G-EEE (current effects, after Empathy session, block 1) • G-EEE (expectation, before Empathy session, block 2) • STADI state* T5: • “Please think back to the experiment – how often did you experience any bodily sensations of pain yourself while witnessing the administration of painful heat stimuli to the other person?” (101 VAS, never – always)* • “Please rate ho | — |
Countries
Germany
Contacts
Public ContactHelena Hartmann
Universitätsklinikum Essen, Klinik für Neurologie
Outcome results
None listed