Nocebo effects on pain and itch
Conditions
Interventions
Trade Name: D-cycloserine
Product Name: D-cycloserine
Pharmaceutical Form: Capsule
Pharmaceutical form of the placebo: Capsule
Route of administration of the placebo: Oral use
Trade Name: Ketanest-S
Sponsors
Leiden University
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: To be eligible, participants must meet all of the following criteria: 1. Between 18 and 35 years of age 2. Good understanding of spoken and written English 3. Native Dutch speaker Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range 200 F.1.3 Elderly (>=65 years) no F.1.3.1 Number of subjects for this age range
Exclusion criteria
Exclusion criteria: A potential subject who meets any of the following exclusion criteria will be excluded from participation in this study: 1. History of serious or chronic medical or psychiatric conditions 2. History of chronic pain or itch conditions 3. Experiencing pain or itch on the day of testing 4. Currently using antihistamines, analgesic medication, or itch-reducing medication (in the 12 hours prior to testing) 5. Recent use of psychotropic drugs (including recreational drugs such as cannabis and psychotropic prescription-medication; in the past month) 6. Currently being (or intending to become) pregnant, or currently breastfeeding 7. Colour-blindness 8. Body Mass Index under 16 or over 30 9. Meeting any exclusion criteria for entering the MR scanner (e.g., permanent metal parts in the body) 10. Having a too high threshold for pain (where high pain cannot be induced with temperatures lower than 49.5 °C) or not responding to histamine (no itch response)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Primary end point(s): The main study parameter is the magnitude of induced nocebo effects on self-reported pain and itch in the first evocation phase as compared between the pharmacological groups. The magnitude of the induced nocebo effects on pain and itch is measured as the difference between self-reported pain and itch on a Numeric Rating Scales between conditioned and control evocation trials in early trials of the first evocation phase.;Timepoint(s) of evaluation of this end point: During the single experimental session, in early trials of the first evocation phase for each sub-study.;Main Objective: The primary objective is to test the role of NMDA receptor-dependent learning in an experimental model of conditioned nocebo effects on self-reported pain (sub-study 1) and itch (sub-study 2). Secondary objectives are to examine the role of NMDA manipulations and related neural correlates during the induction, evocation, and attenuation of nocebo effects using statistical learning models. We also aim to explore neural differences between control stimulations and nocebo-augmented pain and itch. Lastly, the moderating effects of psychological variables measured with questionnaires on the nocebo effect will also be explored. ;Secondary Objective: Secondary objectives for both sub-studies are: 1. To examine neural activations during the induction of nocebo effects on pain or itch. Multivariate pattern analysis will be used to investigate differences in BOLD responses during the induction of nocebo effects and thereby classify participants into pharmacological treatment groups. 2. To examine neural activations during the evocation of nocebo effects on pain or itch. 3. To explore neural activations between the experience of pain and itch. 4. To explore neural activations between the experience of nocebo-augmented sensations and the experience of control sensory stimulations. 5. To predict the magnitude of induced nocebo effects on pain or itch, based on patterns of B | — |
Secondary
| Measure | Time frame |
|---|---|
| Secondary end point(s): Secondary study endpoints for both sub-studies are: - The classification accuracy (into pharmacological groups), indicating that patterns of activation in the network of a priori ROIs form a model that can detect differences in neural activations during the induction of nocebo effects. - The classification accuracy (into pharmacological groups), indicating that patterns of activation in the network of a priori ROIs form a model that can detect differences in neural activations during the first evocation phase. - The classification accuracy, indicating that patterns of activation in the network of a priori ROIs form a model that can detect commonalities and differences in neural activations between the experience of pain and itch. - The classification accuracy, indicating that patterns of activation in the network of a priori ROIs form a model that can detect common neural activations between the experience of nocebo-augmented pain and nocebo-augmented itch, thereby indicating a signature of activations relevant to the manifestation of nocebo effects, independent from sensory input. - The prediction accuracy, indicating that patterns of activation in the network of a priori ROIs form a model that can predict the magnitude of induced nocebo effects based on patterns of activations during the induction of nocebo effects. - The moderation of the magnitude of induced nocebo effects in the first evocation phase by scores on the psychological questionnaires. Secondary parameters for the pain sub-study only: - The magnitude of nocebo effects on pain present after nocebo attenuation, between the pharmacological groups, as measured in early trials of the second evocation phase relative to early trials of the first evocation phase. - The classification accuracy (into pharmacological groups) indicating that patterns of activation in the network of a priori ROIs form a model that can detect differences in neural activations during the attenuation of noc | — |
Countries
Netherlands
Contacts
Public ContactInstitute of Psychology
Leiden University
Outcome results
None listed