Do Emotions Affect Mechanical Pain Thresholds?

Study Overview
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Brief Summary
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The purpose of this study is to investigate if different emotional states could influence mechanical pain thresholds.

Detailed Description
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Participants will be randomized into 4 different groups watching different short video-clips (2.20 min). The negative emotions group will watch an uncomfortable short video containing violence and blood, the positive emotions group will watch a video containing a stand-up comedy show, the neutral emotions group will watch a video with Swedish nature, and the control group will just wait for 2.20 min, without any instructions about what to think about. Pressure pain thresholds will be measured with an algometer before and after the video-clip interventions.

Official Title
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Do Emotions Affect Mechanical Pain Thresholds?

Conditions
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Pain

Intervention / Treatment
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* Behavioral: Emotion induction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Above 18 years of age, fluent in Swedish. Exclusion Criteria: Pain anywhere in body during the test session, known neurological disease.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Negative emotional condition<br>The participant will watch a short video-clip with negative emotional content. | Behavioral: Emotion induction<br>* The participants will receive different emotion inductions through short video clips.<br>* Other names: Negative emotion induction, positive emotions induction, neutral emotions induction, control.;|
| Experimental: Positive emotional condition.<br>The participant will watch a short video-clip with positive emotional content. | Behavioral: Emotion induction<br>* The participants will receive different emotion inductions through short video clips.<br>* Other names: Negative emotion induction, positive emotions induction, neutral emotions induction, control.;|
| Experimental: Neutral condition.<br>The participant will watch a short video-clip with neutral emotional content. | Behavioral: Emotion induction<br>* The participants will receive different emotion inductions through short video clips.<br>* Other names: Negative emotion induction, positive emotions induction, neutral emotions induction, control.;|
| Experimental: Control condition.<br>The participant will not watch a video-clip, but will wait without specific instructions about what to think about. | Behavioral: Emotion induction<br>* The participants will receive different emotion inductions through short video clips.<br>* Other names: Negative emotion induction, positive emotions induction, neutral emotions induction, control.;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pressure pain threshold | Pressure pain threshold value after each different emotion intervention and control compared to before each emotion intervention and control. | Measurements will be conducted at the test session, which will have a duration of approximately 20 minutes for each participant. |