Patients with chronic back pain
Conditions
Interventions
Group 1: Patients with chronic back pain participate in an effort task. This task examines decision-making behavior, reaction time, and the degree of effort, and records subjective assessments of empa
Sponsors
Universitätsklinikum Essen, Klinik für Neurologie
Eligibility
Sex/Gender
All
Age
18 Years to 80 Years
Inclusion criteria
Inclusion criteria: *Group 1: patients with chronic back pain - Upper, middle, and/or lower back pain - Specific and/or unspecific pain - Eligibility for patients without a valid diagnosis will be confirmed by a study physician to ensure that they meet the inclusion criteria for Group 1 *Group 2: healthy participants who have never before experienced chronic pain * Fluent in German * Written voluntary consent to participate * Abstinence from consuming alcohol 24h before each session
Exclusion criteria
Exclusion criteria: General exclusion criteria: *Active and past use of psychoactive substances (Required abstinence at least 3 months prior to testing session) *Serious medical conditions (e.g. illnesses of the cardiovascular system, respiratory system, nervous system, gastrointestinal system, metabolism, etc.) *Allergies (e.g., contact allergies) *Allergy medication intake on the day of testing *Injuries/scars, skin damage (e.g., sunburn), tattoos, open wounds or inflammation/eczema of the skin at the site of thermal stimulation *Participation in an experimental study on the topics of 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 *Surgical interventions in the last 3 months, especially if not fully healed/currently painful *Impaired or uncorrected vision that cannot be corrected by contact lenses or glasses *Astigmatism that cannot be corrected by contact lenses or glasses *Acute infections *For all MRI measurements: Any contraindication for an MRI measurement (metal or electrical implants, pregnancy, claustrophobia, working with metal, etc.); If a patient does not fulfil the MRI safety criteria, they will be invited to complete Day 1 in the lab and receive an aliquote payment. Further exclusion criteria for healthy participants : *Use of over-the-counter pain medication 72 hours before participation *Regular intake of over-the-counter pain medication (No more than 1x per month) *Regular intake of medication in the last 7 days (Except for: hormonal contraceptives or medication such as anti-allergic drugs) *Acute or history of mental disorders (e.g. manifest depression, schizophrenia, substance use disorders) - Depression: minimum of one year post therapy, no remission *Chronic or acute pain (headaches, backpain, radicular pain, neuropathic pain, unspecific pain indicating a pain disorder) - No more than 1x per month Further exclusion criteria for patients with chronic pain: *Intake of high-dose pain medication (in particular, high-dose opioids > 100mg morphine equivalent per day) *Chronic pain disorders other than chronic back pain (especially headaches, radicular pain, neuropathic pain) and disorders that might cause chronic back pain but are more associated with a specific illness (e.g., multiple sclerosis or Parkinson’s) *Acute or history of mental disorders not associated with chronic pain (e.g. schizophrenia)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The study includes two sessions conducted on separate days. Day 1 takes place at the MR scanner and includes one questionnaire time point (T1), and Day 2 takes place in the laboratory and includes four questionnaire time points (T2–T5). ------ For each trial of the 'effort task', we will measure the following variables: * Empathy for pain H1 Pain intensity ratings: of the perceived intensity of pain felt by the other person, to measure the more cognitive-evaluative aspect of empathy for pain / ‘How painful do you think was this stimulus for the other person?’ / VAS rating 0-100 (‘not painful at all’ - ‘extremely painful’) H2 Unpleasantness ratings: of participants’ own subjective feeling of unpleasantness when seeing another person in pain, to measure the more affective aspect of empathy for pain / ‘How unpleasant did it feel for you when the other person was stimulated?’ / VAS rating 0-100 (‘not unpleasant at all’ - ‘extremely unpleasant) * Prosocial behavior H3: Choice: to measure if participants choose to help the other person or not / Logged per trial (0 or 1), based on participants decision (0 = not helping / 1 = helping) H4: Exerted force: to measure how much physical strength participants invest when helping the other person (only for trials in which participants chose the helping option) / Calculated as AUC (area under the curve) of the effort exerted during the 3-sec window | — |
Secondary
| Measure | Time frame |
|---|---|
| Additionally, for each trial of the 'effort task', we will measure the following variable: * Reaction time: trial-by-trial to measure motivation to help, based on how long it takes participants to make a choice / calculated as the time (in milliseconds) from stimulus onset to button press during the decision phase * Heat pain duration: (in seconds) that measures how long the heat pain stimulus was that the other person received / Logged per trial (2-20s), based on participants decision and performance ------ On Day 1 - T1 we will measure the degree of chronicity of pain in the group with patients with chronic pain with the DSF questionnaire (German pain questionnaire / ‘Deutscher Schmerzfragebogen’; Nagel et al., 2002): * Chronic pain duration: to measure how long participants have been experiencing chronic pain. / Assessed using an adapted version of item 7.a) from the DSF, replacing the original single choice categories with an open numeric response field (months/years) to allow for more precise reporting / ‘How long have you been experiencing this pain?’ * Chronic pain severity: graded into 4 hierarchical classes according to von Korff et al. (1992) to measure the severity of the chronic pain. / Assessed using multiple questions from the DSF that measure the pain intensity (e.g., ‘Please rate your current pain intensity.’), the disability caused by pain (e.g., ‘To what extent has pain interfered with your leisure and social activities in the last 3 months?’) and the amount of disability days in the last 3 month. The questions and calculation scheme can be found in the DSF handbook (Petzke et al., 2020). ------ Before and after the 'effort task' on day 2 , we will measure three variables adapted from the NASA Task Load Index (Hart & Staveland, 1988) / Questions regarding how effortful, unpleasant and physical demanding it was to exert effort (e.g., ‘How physically strenuous was it to stay above the yellow line?’) / VAS ratings 0-100 (‘not at all’ - ‘ext | — |
Countries
Germany
Contacts
Public ContactHelena Hartmann
Universitätsklinikum Essen, Klinik für Neurologie
Outcome results
None listed