The Effects of a Brief Mindfulness Intervention on Emotional Responses and the Moderating Role of Interoception

Study Overview
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Brief Summary
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This study examines the effects of a brief mindfulness intervention (body scan) on emotional responses (e.g., affect, heart rate variability (HRV)) compared to an active control group. Another aim is to assess whether the effects of the mindfulness intervention can be augmented by optimizing positive expectations. The moderating role of interception on the mindfulness intervention's effects will also be examined.

Detailed Description
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This 3-armed study examines the effects of a brief mindfulness intervention (audio-guided body scan) on emotional responses (e.g., affect, and heart rate variability (HRV)) compared to an active control group (listening to an audio-book). Another aim is to assess whether the effects of the mindfulness intervention can be augmented by optimizing positive expectations. The moderating role of interception (i.e., interoceptive accuracy as assessed by the Schandry task) on the mindfulness intervention's effects will also be examined.

Official Title
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The Effects of a Brief Mindfulness Intervention on Emotional Responses and the Moderating Role of Interoception

Conditions
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Healthy Participants

Intervention / Treatment
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* Behavioral: Body Scan
* Other: Audio-book


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: fluent in the German language ability to give informed consent Exclusion Criteria: cardiovascular disease (previous myocardial infarction, hypertension) neurological disorders (epilepsy, stroke, multiple sclerosis) continuous medication intake (exceptions: contraceptives, nutritional supplements, L-thyroxine for hypothyroidism are allowed) pregnancy

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: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Audio-guided mindfulness-based intervention (body scan)<br> | Behavioral: Body Scan<br>* The body scan intervention aims to raise one's awareness of one's own body. It is considered a relaxation, meditation or mindfulness intervention. During the body scan participants will walk through his or her body by focusing their mind on specific body parts without analyzing, judging or reacting.<br>|
| Experimental: Enhanced Audio-guided mindfulness-based intervention (body scan)<br>Participants undergo the same audio-guided body scan intervention. However, in this arm the instruction focuses on the positive effects of mindfulness-based interventions and body scan aiming to optimize participants' interventions outcome expectations of the intervention. The idea of this arm is to assess whether the effects of the mindfulness-based intervention can be augmented by boosting participants positive expectations prior to the intervention. | Behavioral: Body Scan<br>* The body scan intervention aims to raise one's awareness of one's own body. It is considered a relaxation, meditation or mindfulness intervention. During the body scan participants will walk through his or her body by focusing their mind on specific body parts without analyzing, judging or reacting.<br>|
| Active Comparator: Audio-Book<br>Participants in this group listen to an audio-book for the same duration as the participants in the two experimental groups. | Other: Audio-book<br>* Participants listen to an audio book for the same amount of time as the body scan groups<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in affect | Participants are asked to rate adjectives regarding their current mood (positive and negative) at two time points (baseline and after body scan or active control intervention) on a questionnaire. Change scores are calculated (post- minus pre-scores). Instrument: Positive and Negative Affect Scale (PANAS) by Watson, Clark, and Tellegen (1988) is a self-report questionnaire that consists of two 10-item scales to measure both positive and negative affect. Each item is rated on a 5-point scale of 1 (not at all) to 5 (very much). Range for sum score of positive/negative affect: 10-50. For positive affect higher scores are better; for negative affect lower scores are better. | Change from pre (baseline) to post scores (30 minutes later) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in perceived stress | Participants are asked to rate how stressed they feel at the moment at two time points (baseline and after body scan or active control intervention) on a questionnaire (VAS: item ranges from 0 (not stressed at all) - 100 (very stressed). Change scores are calculated (post- minus pre-scores). More negative change scores are better since it indicates a stronger stress reduction (maximum reduction: -100). Higher positive change scores are worse since this indicates an increase in perceived stress (maximum increase: +100). Range of change scores: -100 - +100). | Change from pre (baseline) to post scores (30 minutes later) | 
| Change in heart rate variability (HRV) | Heart rate variability (HRV) describes the variations between two successive heart beats and is considered a measure for cardiac adaptation to internal and external stimuli. HRV is considered an important transdiagnostic biomarker of health. HRV is frequently quantified using time- domain measures such as the standard deviation of NN intervals (SDNN) and the root mean square of successive differences between normal heartbeats (RMSSD). For HRV levels higher scores are better | Change from pre (baseline) to post scores (30 minutes later) | 
| Change in interoceptive accuracy | The heartbeat perception task (Schandry, 1981) encompasses several trials in which participants are instructed to silently count their heartbeats and report the number they counted after each trial. Reported and actual number of heart beats (as assessed by ECG) will be used to calculate a heartbeat detection index (error score). | Change from pre (baseline) to post scores (30 minutes later) | 
| Change in state anxiety and depression | The State-Trait-Anxiety-Depression-Inventory (STADI) (Laux, L. Hock, M., Bergner-Köther, R., Hodapp, V. & Renner, K., 2013) measures participants' state anxiety (10 items) and state depression (10 items) severity. Each item can be answered on a 4-point-scale from 1 (not at all) - 4 (very much). Sum scores are calculated and range from 10-40 for each scale (depression and anxiety). Lower scores indicate lower severity (i.e., less negative mood). | Change from pre (baseline) to post scores (30 minutes later) |