Brain Substrates for Cardiovascular Stress Physiology

Study Overview
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Brief Summary
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Transcranial infrared laser stimulation is a non-invasive neuromodulation technique. The study will examine the effect of transcranial infrared laser stimulation on cardiovascular and metabolic responses to stress.

Detailed Description
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Physiological responses to stress may be a potential pathway by which psychological stress relates to cardiovascular disease. Disproportionate (metabolically exaggerated) stressor-evoked cardiovascular reactions may accelerate atherosclerosis or influence risk of greater cardiovascular disease endpoints. The aim of this project is to use an experimental approach to examine if neuromodulation (transcranial infrared laser stimulation) alters stressor-evoked metabolic and cardiovascular responses.

Official Title
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Brain Substrates for Cardiovascular Stress Physiology

Conditions
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Stress Reaction

Intervention / Treatment
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* Other: Low-level laser therapy (LLLT)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-30 years old Exclusion Criteria: History of a diagnosed chronic medical or neurological disorder Current pregnancy Current illness or infection (e.g., cold, flu) Any condition that would prohibit them from engaging in physical exercise

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 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: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Sham<br>Participants will receive sham laser to the right forehead. | Other: Low-level laser therapy (LLLT)<br>* Sham Comparator: Participants will receive 8 counts of 60 seconds of the same laser to the right forehead, however the laser power will be turned off and will be 0 Watts. Transcranial infrared laser stimulation: Participants will receive 8 counts of 60 seconds of transcranial infrared laser stimulation to the right forehead. The wavelength will be 1064 nm and the laser power will be 3.4 Watts.<br>|
| Active Comparator: Transcranial infrared laser stimulation<br>Participants will receive transcranial infrared laser stimulation to the right forehead. | Other: Low-level laser therapy (LLLT)<br>* Sham Comparator: Participants will receive 8 counts of 60 seconds of the same laser to the right forehead, however the laser power will be turned off and will be 0 Watts. Transcranial infrared laser stimulation: Participants will receive 8 counts of 60 seconds of transcranial infrared laser stimulation to the right forehead. The wavelength will be 1064 nm and the laser power will be 3.4 Watts.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Oxygen consumption in response to acute psychological stress | This measurement takes into account oxygen consumption at baseline and during the stress task. | Immediately following intervention (up to 60 minutes) | 
| Heart rate in response to acute psychological stress | This measurement takes into account heart rate at baseline and during the stress task. | Immediately following intervention (up to 60 minutes) | 
| Additional heart rate in response to acute psychological stress | This measurement takes into account additional heart rate at baseline and during stress. | Immediately following intervention (up to 60 minutes) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perceived stress | Ratings of perceived stressfulness (1 = not at all stressful, 7 = very stressful) of the acute psychological stress task | Immediately following intervention (up to 60 minutes) |