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Completed

NCT Number: NCT02882529

Systematically Assessing Effects of Colored Light on Humans With a Multi-modal Approach (Substudy 2 of 7)

NOTE: This is the second of in total 7 sub-studies related to the Ethics Committee of the Canton of Bern Ref. No. KEK-BE 2016-00674. This sub-study includes 50 participants and 6 arms, in total 350 participants will be assessed in all 7 sub-studies.

General study information: This is a randomized, cross-over, quantitative study, which investigates physiological variables, mood, and affect of healthy participants in response to colored light exposure. The Participants take part in 5-8 arms and are exposed to colored light only, or are additionally asked to solve cognitive tasks during the colored light exposure. Primary aim is to measure the change in several physiological variables, mood, and affect during colored light exposure of 15 or 45 minutes. The risk for the participants is negligible and comparable to the risk during daily life.

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Key information

Conditions

Exposure to Man-made Visible Light Pathologic Processes Pathological Conditions, Signs and Symptoms Respiration Disorders Respiratory Aspiration Respiratory Tract Diseases

Age range

18 year–50 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University of Bern, Institute of Complementary Medicine

Bern, 3012, Switzerland

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Normal color vision
  • Right handed
  • Written informed consent

Exclusion criteria

  • Smoking
  • Any kind of diagnosed sleep disorder or neurological or psychiatric disorder in the last 3 months
  • Acute severe traumas
  • Chronic diseases with the necessity for medication
  • Use of recreational drugs
  • Regular intake of medication that would affect the outcome measures
  • Regular excessive alcohol use (> 18 standard units / week)
  • Transmeridian travel in the last month (crossed > 1 time zone border)
  • Night shift word during the last month

Treatment and study plan

Visible light exposure

Other

Subjects will be exposed to visible colored light for 15 minutes. The visible light will be generated by red-green-blue light emitting diodes light cans.

Primary outcomes

  1. Change in cerebral tissue oxygen saturation during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

  2. Change in cerebral hemoglobin concentration during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

    3 hemoglobin concentrations will be analyzed: of oxygenated hemoglobin, of deoxygenated hemoglobin, and of total hemoglobin.

  3. Change in variables of the heart rate variability during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

    Heart rate variability variables are: the standard deviation of the NN intervals (SDNN), the square root of the mean of the sum of the squares of differences between adjacent NN intervals (RMSSD), the power of the high-frequency component (HF, 0.15-0.4 Hz), the power of the low-frequency component (LF, 0.04-0.15 Hz), the power of the very low-frequency component (VLF, <0.04 Hz), normalized LF and HF components, and the LF/HF ratio.

  4. Change in variables of the electro-dermal activity during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

    The tonic and phasic parts of the electro-dermal activity will be analyzed.

  5. Change of the blood pressure during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

    The systolic, diastolic, and mean arterial pressure will be analyzed.

  6. Change of the partial pressure of carbon dioxide during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

    The partial pressure of carbon dioxide will be assessed by the end-tidal partial pressure of carbon dioxide of the exhalation air.

  7. Change of the respiration rate during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

  8. Change of the heart rate during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

  9. Change of the pulse-respiratory quotient during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

    The pulse-respiratory quotient will be calculated as heart rate divided by the respiration rate.

  10. Change of the arterial oxygen saturation during colored light exposure compared with a baseline and a recovery period

    Time frame: 43 minutes (8 min baseline, 15 min colored light exposure, 20 min recovery)

Sponsors and collaborators

Lead sponsor

University of Bern

Other

Registry information

Official study title

Systematically Assessing Effects of Colored Light on Humans With a Multi-modal Approach

Important dates

Study start
2017
Primary completion
2018
Study completion
2021
First posted
Aug 30, 2016
Registry last updated
Sep 17, 2021

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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