Cognitive Enhancement Through Transcranial Laser Therapy

Study Overview
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Brief Summary
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This is a mechanism-driven translational project to test the efficacy of transcranial low-level light/laser therapy (LLLT), for enhancing cognitive function in middle-aged and older adults and participants with Mild Cognitive Impairment.

Detailed Description
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The goal of this project is to test the efficacy of LLLT to enhance neurocognitive function in middle-aged adults and examine the modulating influences of carotid atherosclerosis. The specific aims will be accomplished in a randomized controlled trial (RCT) by examining cognitive test performance and blood oxygen level-dependent (BOLD) response to a working memory task in middle-aged and older adults and participants with Mild Cognitive Impairment pre- and post- six-week long intervention of LLLT or placebo. In addition, the investigators will examine if carotid artery intima-media thickness (IMT) moderates the therapeutic effects of LLLT.

Official Title
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Cognitive Enhancement Through Transcranial Laser Therapy

Conditions
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Healthy Participants, Mild Cognitive Impairment

Intervention / Treatment
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* Device: LLLT
* Device: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and postmenopausal women, aged 45 and older Participants with Mild Cognitive Impairment Exclusion Criteria: neurological disease (e.g., large vessel stroke, seizure disorder, Parkinson's disease, Alzheimer's disease, clinically significant traumatic brain injury with loss of consciousness > 30 minutes, multiple sclerosis, or brain infection/meningitis baseline IQ < 85 placing them below the average range of intellectual functioning major psychiatric illness (e.g., schizophrenia, bipolar disorder) or substance abuse (diagnosed abuse and/or previous hospitalization for substance abuse) severe cardiovascular disease (e.g., pacemaker), chronic obstructive pulmonary disease, liver or kidney disease, inflammatory illness

Ages Eligible for Study
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Minimum Age: 45 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: LLLT<br>Six weekly sessions of LLLT. The treatment will consist of applying light of a specific wavelength (1064 nm) using a laser diode supplied by Cell Gen Therapeutics, LLC (CG-5000 laser, HD Laser Center, Dallas, TX, USA). Each laser stimulation session will consist of total 8 min, with eight 1 min/cycle treatments alternating between two locations on the right forehead. | Device: LLLT<br>* The treatment will consist of applying light of a specific wavelength (1064 nm) using a laser diode supplied by Cell Gen Therapeutics, LLC (CG-5000 laser, HD Laser Center, Dallas, TX, USA).<br>|
| Active Comparator: Placebo<br>The control group will undergo the same procedure as the treatment group, but will receive brief (5-s) stimulation to the intended site on the forehead, followed by 55 s of no stimulation, for each 1-min cycle. Thus the control group will receive approximately 1/12th of the cumulative energy density as the treatment group. This is sufficient to provide a brief sensation of slight heat (as active placebo) at the onset of each one-minute cycle, using a fraction of the energy received by the experimental group. | Device: Placebo<br>* The treatment will consist of applying light of a specific wavelength (1064 nm) using a laser diode supplied by Cell Gen Therapeutics, LLC (CG-5000 laser, HD Laser Center, Dallas, TX, USA). However, the placebo group will receive approximately 1/12th of the cumulative energy density as the treatment group.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Psychomotor Vigilance Task (PVT) | The psychomotor vigilance task (PVT) is a sustained-attention, reaction-timed task that measures the consistency with which subjects respond to a visual stimulus. | Time 1 represents PVT performance (reaction time in msec) at baseline, Time 2 represents PVT performance (reaction time in msec) six weeks later. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brain Blood Oxygen Level Dependent Response to Working Memory (2Back) Task | The outcome represents a score on a scale - brain activation in response to a working memory task (t-statistic). The range is approximately -15 to +15. Positive scores reflect greater engagement of working memory brain regions and better performance. | T1 represents score at baseline; T2 represents follow-up score, 6 weeks later | 
| Working Memory (2 Back Task) | 2Back task performance (%Correct) | T1 represents 2back % Correct at baseline; T2 represents 2back % Correct 6 weeks later | 
| Working Memory (2 Back Task) | 2Back task performance (Reaction Time in msec) | T1 represents 2back Reaction Time (RT) in msec at baseline; T2 represents Reaction Time (RT) in msec 6 weeks later |