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Bright Light Therapy for Treatment of Sleep Problems Following Mild Traumatic Brain Injury

Bright Light Therapy for Treatment of Sleep Problems Following Mild Traumatic Brain Injury

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02374918
Enrollment
77
Registered
2015-03-02
Start date
2014-12-31
Completion date
2019-12-31
Last updated
2021-06-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Concussion, Mild, Post-Concussion Symptoms, Sleep Problems

Keywords

Mild traumatic brain injury, Concussion, Sleep problems, Brain imaging, fMRI

Brief summary

The purpose of the research study is to understand the effectiveness of a six-week course of light exposure on cognitive functioning, mood, activity, and sleep in people that have suffered a head injury leading to a concussion.

Detailed description

Mild traumatic brain injuries (mTBI) or concussions are an increasingly prevalent injury in the investigators society. Patients with post-concussion syndrome have been shown to have deficits on tests of short term memory, divided attention, multi-tasking, information processing speed, and reaction time, as well as alteration in mood and emotional functioning. Many patients have other vague complaints including fatigue, dizziness, irritability, sleep disturbances, and chronic headaches. Furthermore, sleep disruption of one of the most common complaints in patients suffering from traumatic brain injuries, with as many as 40 to 65% of patients with mTBI complaining of insomnia. Sleep problems in these patients are associated with poorer outcome, while resolution of the sleep disturbance is associated with improvement in cognitive functioning. Despite recent evidence of the correlation between sleep quality and recovery from traumatic brain injury, and the well-established role of sleep in neural plasticity and neurogenesis, there have been virtually no direct studies of the causal effects of sleep on recovery following mTBI. However, it is quite likely that sleep plays a critical role in recovery following brain injury. A particularly promising non-pharmacologic approach that shows potential in improving/modifying abnormalities of the circadian rhythm and sleep-wake schedule is bright light therapy. For the proposed investigation, the investigators hypothesize that bright light therapy may be helpful in improving the sleep of patients with a recent history of mTBI and may also have other mood elevating effects, both of which should promote positive treatment outcome in these individuals. Bright light therapy may increase the likelihood that they will recover more quickly, benefit more extensively from other forms of therapy, and build emotional and cognitive resilience. This study will also have a healthy control (HC)/effect localization arm that will assist in identifying and mapping the brain systems before and after light exposure so that researchers may develop further insights into the relationship between concussion, light exposure, sleep, and brain function. This healthy control arm will also provide brain targets for study in the analysis of the Main Study Arm.

Interventions

DEVICEmTBI wavelength-1 bright light

6 weeks of daily light exposure, 30 minutes per morning

DEVICEmTBI wavelength-2 bright light

6 weeks of daily light exposure, 30 minutes per morning

DEVICEHC wavelength-1 bright light

30 minutes of light exposure

DEVICEHC wavelength-2 bright light

30 minutes of light exposure

Sponsors

U.S. Army Medical Research Acquisition Activity
CollaboratorFED
University of Arizona
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes

Inclusion criteria

* Age range between 18 and 50. * The primary language of the subjects must be English. * Subjects have experienced a concussion or mTBI within the preceding 18 months, but no sooner that 4 weeks prior to their screening. The occurrence of a concussion or mTBI must be documented by a medical report or other professional witness documentation. * If documented, Glasgow Coma Scale in the range of 13-15 following the injury. * Subjects must have complaints of sleep difficulties that emerged or worsened following the most recent head injury. * At least half of subjects must have evidence of sleep onset insomnia or delayed sleep phase disorder.

Exclusion criteria

* Any other history of neurological illness, current Diagnostic Statistical Manual (DSM-IV) Axis I disorder, lifetime history of psychotic disorder, or head injury with loss of consciousness \> 30 minutes * Complicating medical conditions that may influence the outcome of neuropsychological assessment or functional imaging (e.g., HIV, brain tumor, etc.) * Abnormal visual acuity that is not corrected by contact lenses * Metal within the body, claustrophobia, or other contraindications for neuroimaging * Less than 9th grade education * Excess current alcohol use (more than 2 instances of intake of 5+ drinks (men) when or 4+ drinks (women) when drinking in the past two months, and/or on average drinking \> 2 drinks per day (men); \> 1 drinks per day (women) during the past two months * History of alcoholism or substance use disorder * Significant use of illicit drugs * History of marijuana use within the past 6 weeks and/or use of marijuana before the age of 16. Subjects who engage in shift-work, night work, or who have substantially desynchronized work-sleep schedules (i.e., sleeping later than 10:00 a.m. more than once a week) will be excluded.

Design outcomes

Primary

MeasureTime frameDescription
Sleep Quality - Pittsburgh Sleep Quality Index (PSQI)Post 6-week interventionThe Pittsburgh Sleep Quality Index (PSQI) subscale measurement that was used is overall sleep quality, which is derived from question 6 on the assessment and uses a Likert scale of 0 to 3. A score of 0 represents very good sleep quality (better outcome), while a measurement of 3 represents very bad sleep quality (worse outcome).
Sleep Quality - Actigraphy Sleep EfficiencyPost 6-week interventionSleep Efficiency is the overall percentage of time that the participant was scored as sleeping during their night of sleep (range: 0-100%). Higher percentages suggest higher sleep quality and a better outcome.
Sleep Quality - Actigraphy Wake After Sleep OnsetPost 6-week interventionWake After Sleep Onset (WASO) is how many minutes the participant, during their night of sleep, was determined to be awake after their sleep onset. Sleep onset is defined as a state of at least 2 minutes of uninterrupted sleep. Higher values indicate a worse outcome (range: 1-125 minutes).
Executive Function Task - Multi-Source Interference Task (MSIT)Post 6-week interventionNeural activation during functional magnetic resonance imaging (fMRI) measuring executive functioning using the MSIT.
Performance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsPost 6-week interventionThe Automated Neuropsychological Assessment Metrics (ANAM) is a neuropsychological battery that uses individual tests to measure cognitive efficiency in areas including attention, concentration, reaction time, memory, processing speed, and decision making. Subscale scores are put in terms of a throughput score, which is calculated to be a ratio of correct responses per minute, as a way to measure cognitive efficiency in the participant; as such, the units for the throughput scores would be in terms of correct responses/minute. Higher throughput scores indicate increased levels of cognitive efficiency in the relevant subscale. The throughput score ranges for the ANAM subscales are: code substitution learning: 0-147 responses per minute procedural reaction time: 0-151 responses per minute mathematical processing: 0-145 responses per minute matching to sample: 0-97 responses per minute code substitution delayed: 0-155 responses per minute
Performance on Neuropsychological Assessment - Repeatable Battery for the Assessment of Neuropsychological StatusPost 6-week interventionThe Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) uses all of its subscales to calculate the RBANS total score (index). To obtain the RBANS total score (index), the raw scores of the subtests must first be computed into index scores for their relevant subscale (different subtest raw scores feed into specific subscales) using RBANS specific tables that have scaled scores embedded and are normed for the age of the participant. The index scores of each subscale are then summed together to get the Sum of Index Scores, which has a possible range of 200-800. Once the Sum of Index Scores is found, the total score (index) is then found using another RBANS specific table with scaled scores embedded within it. The total score (index) has a possible range of 40-160, with a higher total score (index) is related to a better outcome.
Performance on Neuropsychological Assessment - Psychomotor Vigilance TaskPost 6-week interventionThe Psychomotor Vigilance Task (PVT) is a task that tests alertness by having the participant press a button every time they see a stimulus image appear on a screen. This image is presented at random 2-10 second intervals throughout the entirety of the task. The reaction time (RT) is one of the PVT measurements and is the time, measured in milliseconds, that it takes for the participant to view the stimulus image and then press the button, confirming that they have indeed viewed the stimulus image at that time. The PVT measures speed using the following equation: 1/RT \* 1000. The PVT measurement used here is average speed, so all the calculated speeds were then averaged over the entire trial period to obtain the final value for that trial at that time point (post-tx 1,2,3). Since the PVT is a timed measurement of reaction times, lower scores are considered 'better' or indicate an increased level of vigilance.
Daytime Sleepiness - Epworth Sleepiness ScalePost 6-week interventionThe Epworth Sleepiness Scale (ESS) is an 8-item questionnaire that characterizes the likelihood of the participant 'dozing off' during typical daily activities over their last 2 weeks, and uses a 0-3 point Likert scale, where 0 corresponds to Would never doze and 3 corresponds to having a High chance of dozing during the activity in question. The ESS score is calculated by adding up all the scores for each question, which means that the ESS score has a range of 0-24, while a higher score indicates that the participant had more issues with daytime sleepiness (worse outcome).
Daytime Sleepiness - Functional Outcome of Sleep QuestionnairePost 6-week interventionThe Functional Outcome of Sleep Questionnaire (FOSQ) questions 1-26 use a 1-4 (ordinal) likert (1 = No difficulty with sleepiness, 4 = Yes, extreme difficulty with sleepiness) and the participant also has the option of putting 0 = I don't do this activity for other reasons. FOSQ questions 27-30 use a 1-4 Likert scale where 1 = Very low in terms of characterizing the level that sleepiness affects different aspects of their intimate romantic relations, while a 4 = High amount of impact on their intimate romantic relations. The FOSQ total score measurement is determined by calculating the mean of all 5 subscale scores and then multiplying that value by 5 (range: 0-24). A higher score indicates that the participant had more issues with daytime sleepiness.
Post-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)Post 6-week interventionThe Rivermead Post-Concussion Symptoms Questionnaire (RPCSQ) will be used to assess post-concussive symptoms related to sleep. All questions on the RPCSQ use a 0 to 4 Likert scale concerning the severity of experiencing differing symptoms, where 0 = not experienced and 4 = severe problem. As such, having a higher score is indicative that the participant is having more serious sleep issues related to their head injury. The RPCSQ subscale measurements that were used below are: RPQ3, which is the summed scores from the first 3 questions on the form, with the subscale total ranging from 0-12, and RPQ13, which is the summed scores from questions 4 to 16 on the form, with the subscale total ranging from 0-52. The RPQ3 subscale is associated with earlier symptom clusters of post-concussive symptoms as they relate to sleep disturbances, while the RPQ13 subscale is associated with later symptom clusters of post-concussive symptoms as they relate to sleep disturbances.

Countries

United States

Participant flow

Recruitment details

Participants were recruited from around the city of Tucson. The first participant was enrolled in December 2014. The Effect Localization Arm completed enrollment in April 2015 and the Treatment Arm completed enrollment in May 2019.

Pre-assignment details

No pre-assignment criteria were needed after enrollment but before study group assignment for the Effect Localization Arm. For the Treatment Arm, participants went through a screening visit before study group assignment and were excluded based on the inclusion/exclusion criteria.

Participants by arm

ArmCount
mTBI Wavelength-1 Bright Light
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
17
mTBI Wavelength-2 Bright Light
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
18
HC Wavelength-1 Bright Light
30 minutes of light exposure HC wavelength-1 bright light: 30 minutes of light exposure
18
HC Wavelength-2 Bright Light
30 minutes of light exposure HC wavelength-2 bright light: 30 minutes of light exposure
18
Total71

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003
Overall StudyLack of Efficacy0011
Overall StudyProtocol Violation2021
Overall StudyWithdrawal by Subject1110

Baseline characteristics

CharacteristicmTBI Wavelength-2 Bright LightmTBI Wavelength-1 Bright LightTotalHC Wavelength-1 Bright LightHC Wavelength-2 Bright Light
Actigraphy - Sleep Efficiency80.98 Percentage of time asleep
STANDARD_DEVIATION 4.71
82.53 Percentage of time asleep
STANDARD_DEVIATION 4.83
81.73 Percentage of time asleep
STANDARD_DEVIATION 4.63
Actigraphy - Wake After Sleep Onset (WASO)11.97 Minutes
STANDARD_DEVIATION 3.23
11.2 Minutes
STANDARD_DEVIATION 3.02
11.60 Minutes
STANDARD_DEVIATION 3.06
Age, Categorical
<=18 years
1 Participants3 Participants7 Participants1 Participants2 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
17 Participants14 Participants64 Participants17 Participants16 Participants
Age, Continuous26.23 years
STANDARD_DEVIATION 7.62
25.53 years
STANDARD_DEVIATION 8.65
23.95 years
STANDARD_DEVIATION 6.41
21.61 years
STANDARD_DEVIATION 2.86
22.28 years
STANDARD_DEVIATION 4.03
ANAM Code Substitution delay - thruput score52.88 correct responses/minute
STANDARD_DEVIATION 8.72
41.06 correct responses/minute
STANDARD_DEVIATION 13.11
46.8 correct responses/minute
STANDARD_DEVIATION 11.96
ANAM Code Substitution Learning - thruput score55.88 correct responses/minute
STANDARD_DEVIATION 12.39
46.78 correct responses/minute
STANDARD_DEVIATION 14.74
51.20 correct responses/minute
STANDARD_DEVIATION 13.79
ANAM Matching to Sample - thruput score33.29 correct responses/minute
STANDARD_DEVIATION 11.55
29.5 correct responses/minute
STANDARD_DEVIATION 8.05
31.34 correct responses/minute
STANDARD_DEVIATION 9.86
ANAM Mathematical Processing - thruput score21.18 correct responses/minute
STANDARD_DEVIATION 7.38
17.89 correct responses/minute
STANDARD_DEVIATION 8.44
19.49 correct responses/minute
STANDARD_DEVIATION 7.89
ANAM Procedural Reaction Time - thruput score97.06 correct responses/minute
STANDARD_DEVIATION 19.41
86.83 correct responses/minute
STANDARD_DEVIATION 19.55
95.26 correct responses/minute
STANDARD_DEVIATION 17.98
ESS total score8.18 units on a scale
STANDARD_DEVIATION 3.28
8.72 units on a scale
STANDARD_DEVIATION 3.32
8.46 units on a scale
STANDARD_DEVIATION 3.27
Ethnicity (NIH/OMB)
Hispanic or Latino
3 Participants2 Participants14 Participants3 Participants6 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
15 Participants15 Participants57 Participants15 Participants12 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants
FOSQ Total Score15.37 units on a scale
STANDARD_DEVIATION 3.82
17.10 units on a scale
STANDARD_DEVIATION 2.18
14.06 units on a scale
STANDARD_DEVIATION 10.86
Post-Concussive Symptoms - Rivermead Post-Concussion Symptoms Questionnaire
RPQ13
15.9 units on a scale
STANDARD_DEVIATION 8
12.3 units on a scale
STANDARD_DEVIATION 13
14.1 units on a scale
STANDARD_DEVIATION 10.9
Post-Concussive Symptoms - Rivermead Post-Concussion Symptoms Questionnaire
RPQ3
3.5 units on a scale
STANDARD_DEVIATION 2.5
3.3 units on a scale
STANDARD_DEVIATION 3
3.4 units on a scale
STANDARD_DEVIATION 2.7
PVT average speed - Run 13.52 responses/second
STANDARD_DEVIATION 0.35
3.27 responses/second
STANDARD_DEVIATION 0.41
3.39 responses/second
STANDARD_DEVIATION 0.39
PVT average speed - Run 23.45 responses/second
STANDARD_DEVIATION 0.42
3.22 responses/second
STANDARD_DEVIATION 0.51
3.33 responses/second
STANDARD_DEVIATION 0.48
PVT average speed - Run 33.50 responses/second
STANDARD_DEVIATION 0.59
3.17 responses/second
STANDARD_DEVIATION 0.43
3.33 responses/second
STANDARD_DEVIATION 0.53
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants1 Participants5 Participants1 Participants3 Participants
Race (NIH/OMB)
Black or African American
1 Participants0 Participants1 Participants0 Participants0 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants2 Participants2 Participants0 Participants
Race (NIH/OMB)
White
17 Participants16 Participants63 Participants15 Participants15 Participants
RBANS total score (index)96.1 units on a scale
STANDARD_DEVIATION 11.5
88.2 units on a scale
STANDARD_DEVIATION 10
92.53 units on a scale
STANDARD_DEVIATION 11.4
Region of Enrollment
United States
18 participants17 participants67 participants18 participants18 participants
Sex: Female, Male
Female
10 Participants12 Participants41 Participants9 Participants10 Participants
Sex: Female, Male
Male
8 Participants5 Participants30 Participants9 Participants8 Participants
Sleep Quality - PSQI1.76 units on a scale
STANDARD_DEVIATION 0.66
1.44 units on a scale
STANDARD_DEVIATION 0.7
1.60 units on a scale
STANDARD_DEVIATION 0.69

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 170 / 180 / 220 / 20
other
Total, other adverse events
0 / 170 / 180 / 220 / 20
serious
Total, serious adverse events
0 / 170 / 180 / 220 / 20

Outcome results

Primary

Daytime Sleepiness - Epworth Sleepiness Scale

The Epworth Sleepiness Scale (ESS) is an 8-item questionnaire that characterizes the likelihood of the participant 'dozing off' during typical daily activities over their last 2 weeks, and uses a 0-3 point Likert scale, where 0 corresponds to Would never doze and 3 corresponds to having a High chance of dozing during the activity in question. The ESS score is calculated by adding up all the scores for each question, which means that the ESS score has a range of 0-24, while a higher score indicates that the participant had more issues with daytime sleepiness (worse outcome).

Time frame: Post 6-week intervention

Population: ESS data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightDaytime Sleepiness - Epworth Sleepiness Scale9.33 units on a scaleStandard Deviation 3.74
mTBI Wavelength-1 Bright LightDaytime Sleepiness - Epworth Sleepiness Scale6.82 units on a scaleStandard Deviation 3.11
Primary

Daytime Sleepiness - Functional Outcome of Sleep Questionnaire

The Functional Outcome of Sleep Questionnaire (FOSQ) questions 1-26 use a 1-4 (ordinal) likert (1 = No difficulty with sleepiness, 4 = Yes, extreme difficulty with sleepiness) and the participant also has the option of putting 0 = I don't do this activity for other reasons. FOSQ questions 27-30 use a 1-4 Likert scale where 1 = Very low in terms of characterizing the level that sleepiness affects different aspects of their intimate romantic relations, while a 4 = High amount of impact on their intimate romantic relations. The FOSQ total score measurement is determined by calculating the mean of all 5 subscale scores and then multiplying that value by 5 (range: 0-24). A higher score indicates that the participant had more issues with daytime sleepiness.

Time frame: Post 6-week intervention

Population: FOSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightDaytime Sleepiness - Functional Outcome of Sleep Questionnaire16.28 units on a scaleStandard Deviation 1.88
mTBI Wavelength-1 Bright LightDaytime Sleepiness - Functional Outcome of Sleep Questionnaire17.33 units on a scaleStandard Deviation 2.39
Primary

Executive Function Task - Multi-Source Interference Task (MSIT)

Neural activation during functional magnetic resonance imaging (fMRI) measuring executive functioning using the MSIT.

Time frame: Post 6-week intervention

Population: Data was collected for this measure but was unable to be analyzed due to issues extracting the data from the computer it was stored on. In addition, MSIT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study 6-weeks after the inital visit.

Primary

Performance on Neuropsychological Assessment - Automated Neuropsychological Assessment Metrics

The Automated Neuropsychological Assessment Metrics (ANAM) is a neuropsychological battery that uses individual tests to measure cognitive efficiency in areas including attention, concentration, reaction time, memory, processing speed, and decision making. Subscale scores are put in terms of a throughput score, which is calculated to be a ratio of correct responses per minute, as a way to measure cognitive efficiency in the participant; as such, the units for the throughput scores would be in terms of correct responses/minute. Higher throughput scores indicate increased levels of cognitive efficiency in the relevant subscale. The throughput score ranges for the ANAM subscales are: code substitution learning: 0-147 responses per minute procedural reaction time: 0-151 responses per minute mathematical processing: 0-145 responses per minute matching to sample: 0-97 responses per minute code substitution delayed: 0-155 responses per minute

Time frame: Post 6-week intervention

Population: ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureGroupValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Procedural Reaction Time - thruput score89.8 correct responses/minuteStandard Deviation 19.5
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Matching to Sample - thruput score30.5 correct responses/minuteStandard Deviation 10.1
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Mathematical Processing - thruput score18 correct responses/minuteStandard Deviation 8.5
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Code substitution delay-thruput score43.3 correct responses/minuteStandard Deviation 14.2
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Code substitution learning -thruput score51.3 correct responses/minuteStandard Deviation 15.8
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Code substitution delay-thruput score56.2 correct responses/minuteStandard Deviation 8.9
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Code substitution learning -thruput score60.3 correct responses/minuteStandard Deviation 10.8
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Procedural Reaction Time - thruput score101.3 correct responses/minuteStandard Deviation 17.9
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Mathematical Processing - thruput score22.1 correct responses/minuteStandard Deviation 8.2
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Automated Neuropsychological Assessment MetricsANAM Matching to Sample - thruput score33 correct responses/minuteStandard Deviation 12.2
Primary

Performance on Neuropsychological Assessment - Psychomotor Vigilance Task

The Psychomotor Vigilance Task (PVT) is a task that tests alertness by having the participant press a button every time they see a stimulus image appear on a screen. This image is presented at random 2-10 second intervals throughout the entirety of the task. The reaction time (RT) is one of the PVT measurements and is the time, measured in milliseconds, that it takes for the participant to view the stimulus image and then press the button, confirming that they have indeed viewed the stimulus image at that time. The PVT measures speed using the following equation: 1/RT \* 1000. The PVT measurement used here is average speed, so all the calculated speeds were then averaged over the entire trial period to obtain the final value for that trial at that time point (post-tx 1,2,3). Since the PVT is a timed measurement of reaction times, lower scores are considered 'better' or indicate an increased level of vigilance.

Time frame: Post 6-week intervention

Population: PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study 6-weeks after the initial visit.

ArmMeasureGroupValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Psychomotor Vigilance TaskPVT average speed - Run 1 - post-tx3.3 responses/minuteStandard Deviation 0.4
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Psychomotor Vigilance TaskPVT average speed - Run 2 - post-tx3.3 responses/minuteStandard Deviation 0.7
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Psychomotor Vigilance TaskPVT average speed - Run 3 - post-tx3.3 responses/minuteStandard Deviation 0.6
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Psychomotor Vigilance TaskPVT average speed - Run 1 - post-tx3.4 responses/minuteStandard Deviation 0.3
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Psychomotor Vigilance TaskPVT average speed - Run 2 - post-tx3.4 responses/minuteStandard Deviation 0.4
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Psychomotor Vigilance TaskPVT average speed - Run 3 - post-tx3.4 responses/minuteStandard Deviation 0.5
Primary

Performance on Neuropsychological Assessment - Repeatable Battery for the Assessment of Neuropsychological Status

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) uses all of its subscales to calculate the RBANS total score (index). To obtain the RBANS total score (index), the raw scores of the subtests must first be computed into index scores for their relevant subscale (different subtest raw scores feed into specific subscales) using RBANS specific tables that have scaled scores embedded and are normed for the age of the participant. The index scores of each subscale are then summed together to get the Sum of Index Scores, which has a possible range of 200-800. Once the Sum of Index Scores is found, the total score (index) is then found using another RBANS specific table with scaled scores embedded within it. The total score (index) has a possible range of 40-160, with a higher total score (index) is related to a better outcome.

Time frame: Post 6-week intervention

Population: RBANs data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightPerformance on Neuropsychological Assessment - Repeatable Battery for the Assessment of Neuropsychological Status88.5 units on a scaleStandard Deviation 10.7
mTBI Wavelength-1 Bright LightPerformance on Neuropsychological Assessment - Repeatable Battery for the Assessment of Neuropsychological Status97.6 units on a scaleStandard Deviation 12.2
Primary

Post-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)

The Rivermead Post-Concussion Symptoms Questionnaire (RPCSQ) will be used to assess post-concussive symptoms related to sleep. All questions on the RPCSQ use a 0 to 4 Likert scale concerning the severity of experiencing differing symptoms, where 0 = not experienced and 4 = severe problem. As such, having a higher score is indicative that the participant is having more serious sleep issues related to their head injury. The RPCSQ subscale measurements that were used below are: RPQ3, which is the summed scores from the first 3 questions on the form, with the subscale total ranging from 0-12, and RPQ13, which is the summed scores from questions 4 to 16 on the form, with the subscale total ranging from 0-52. The RPQ3 subscale is associated with earlier symptom clusters of post-concussive symptoms as they relate to sleep disturbances, while the RPQ13 subscale is associated with later symptom clusters of post-concussive symptoms as they relate to sleep disturbances.

Time frame: Post 6-week intervention

Population: The RPCSQ was not administered to the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureGroupValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightPost-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)RPQ33 score on a scaleStandard Deviation 2.4
mTBI Wavelength-2 Bright LightPost-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)RPQ1312.8 score on a scaleStandard Deviation 11.1
mTBI Wavelength-1 Bright LightPost-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)RPQ32.7 score on a scaleStandard Deviation 2.7
mTBI Wavelength-1 Bright LightPost-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)RPQ1311.1 score on a scaleStandard Deviation 8.3
Primary

Sleep Quality - Actigraphy Sleep Efficiency

Sleep Efficiency is the overall percentage of time that the participant was scored as sleeping during their night of sleep (range: 0-100%). Higher percentages suggest higher sleep quality and a better outcome.

Time frame: Post 6-week intervention

Population: Actigraphy data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightSleep Quality - Actigraphy Sleep Efficiency82.57 percentage of time asleepStandard Deviation 4.2
mTBI Wavelength-1 Bright LightSleep Quality - Actigraphy Sleep Efficiency83.43 percentage of time asleepStandard Deviation 5.11
Primary

Sleep Quality - Actigraphy Wake After Sleep Onset

Wake After Sleep Onset (WASO) is how many minutes the participant, during their night of sleep, was determined to be awake after their sleep onset. Sleep onset is defined as a state of at least 2 minutes of uninterrupted sleep. Higher values indicate a worse outcome (range: 1-125 minutes).

Time frame: Post 6-week intervention

Population: Actigraphy data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightSleep Quality - Actigraphy Wake After Sleep Onset11.66 minutesStandard Deviation 2.91
mTBI Wavelength-1 Bright LightSleep Quality - Actigraphy Wake After Sleep Onset10.4 minutesStandard Deviation 3.32
Primary

Sleep Quality - Pittsburgh Sleep Quality Index (PSQI)

The Pittsburgh Sleep Quality Index (PSQI) subscale measurement that was used is overall sleep quality, which is derived from question 6 on the assessment and uses a Likert scale of 0 to 3. A score of 0 represents very good sleep quality (better outcome), while a measurement of 3 represents very bad sleep quality (worse outcome).

Time frame: Post 6-week intervention

Population: The PSQI was not administered to the HC wavelength-2 and HC wavelength-1 arms of this study.

ArmMeasureValue (MEAN)Dispersion
mTBI Wavelength-2 Bright LightSleep Quality - Pittsburgh Sleep Quality Index (PSQI)1.28 score on a scaleStandard Deviation 0.67
mTBI Wavelength-1 Bright LightSleep Quality - Pittsburgh Sleep Quality Index (PSQI)1.35 score on a scaleStandard Deviation 0.7

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026