Neurobehavioral Changes Following Spaceflight Stressors
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age21-60
SponsorUniversity of Pennsylvania
About this trial
This study aims to investigate the impairing effects of known central nervous system (CNS) stressors in a controlled environment in order to predict and mitigate analogous risks in spaceflight. Up to 56 healthy individuals aged 25-60 will spend approx. 110 hours in a laboratory, where they will be exposed to 27 hours of sleep deprivation and will consume alcohol to reach a BAC of 0.08 on a separate day. They will perform cognitive and sensorimotor tasks and undergo MRIs and blood draws.
Eligibility criteria
This trial accepts healthy volunteersQualifiers
Age between 21-60 years.
Free of psychological, psychiatric or physical conditions that preclude participation.
BMI between 18.5 and 35.
Self-reported regular sleep schedule; able to maintain their sleep schedule during the course of the study.
Disqualifiers
Alcohol or drug abuse in the past year based upon history and urine toxicology screen.
Potential alcohol abuse or heavy drinking in the past year, based on self-report (AUDIT-C Q2 score above 1 or Q3 score above 2).
Alcohol-naive based on self-report (AUDIT-C Q1 score of 0).
Allergies, conditions or circumstances that preclude alcohol consumption, including use of medication or supplements (prescription or over the counter) that could interfere with study participation or make it hazardous for a subject to partake (e.g., anticholinergics; antipsychotics; lithium; psychotropic drugs not otherwise specified), or for which alcohol consumption should be limited or avoided (e.g. items identified on NIAAA's 'Harmful Interactions' list).
Trial design
Design model
Crossover
Treatments tested in this trial
Alcohol Administration
Other interventionFor the alcohol administration condition (ALC), subjects will consume alcohol within a window of approximately fifteen minutes in the morning in order to induce a blood alcohol content (BAC) level of 0.08%, in the form of 80-proof vodka mixed with fruit juice or clear, noncaffeinated soda at a 1:3 ratio. The specific dosage is determined by the Widmark formula, factoring in each individual's body weight and sex. BAC will be measured by a NHTSA-approved evidential breath testing (EBT) device, which measures breath alcohol content (BrAC, in grams per 210 liters of breath) and converts it to BAC (in g/100ml or g/dl). BAC will be measured before and after every task until subjects go to bed at 11 PM, at which point their BAC is expected to be at or close to 0.00%. Subjects will undergo an MRI (shortly after alcohol consumption at what is anticipated to be their highest level of intoxication to capture the impairing effects) and two blood draws (in the morning and afternoon).
Sleep Deprivation
BehavioralFor the sleep deprivation condition (SD1\&2), subjects will remain awake for 27 hours from 8 AM until 11 AM the following morning (SD1). They will perform testing at regular intervals throughout the day and overnight, and they have two blood draws during the extended wake period. Subjects will undergo an MRI after approximately 25 hours of wakefulness, followed by a three-hour nap opportunity from 11 AM until 2 PM. They will then remain awake from 2 PM until 11 PM for testing and meals before returning to the standard sleep period of 11 PM to 8 AM (SD2). Caffeine will not be available to subjects during this period nor will it be available at any other time during the study.
Control
Other interventionDuring the control condition (CTRL), subjects will have no stressor intervention. They will not consume alcohol and they will sleep during the standard period of 11 PM to 8 AM. They will perform testing at regular intervals throughout the day. They will undergo an MRI in the morning, and have two blood draws (in the morning and afternoon).
Treatment groups
56 Participants
are divided into 6 treatment groups6
Treatment groupsSee each treatment group below.
Group A: Group A: CTRL - ALC - SD1&2Experimental treatment 3 interventions
Group B: Group B: ALC - CTRL - SD1&2Experimental treatment 3 interventions
Group C: Group C: SD1&2 - CTRL - ALCExperimental treatment 3 interventions
Group D: Group D: CTRL - SD1&2 - ALCExperimental treatment 3 interventions
Group E: Group E: ALC - SD1&2 - CTRLExperimental treatment 3 interventions
Group F: Group F: SD1&2 - ALC - CTRLExperimental treatment 3 interventions
Trial outcomes
Primary outcomes
1
Psychomotor Vigilance Task (PVT) lapses
The number of lapses in the Psychomotor Vigilance Task (PVT) in the Cognition battery, a 3-minute task that records reaction times to visual stimuli and has been validated as a sensitive measure of vigilant attention. Subjects are instructed to monitor a blank box on the screen, and to hit the space bar once a millisecond counter appears in the box and starts incrementing. The box displays the reaction time for one second then resets, with random interstimulus intervals between 2-5 seconds. Lapses are defined as response times greater than or equal to 355 milliseconds. The results are reported as the number of lapses with a standard deviation for the impaired condition and the non-impaired control state. More lapses suggest greater impairment.
Time frame
From Study Day 2 through Study Day 6 (to include each of the three conditions: ALC, CTRL, SD1&2).Secondary outcomes
1
Cognition Test Battery Speed
A single variable representing response time across 10 Cognitive tasks that cover a range of cognitive domains with known cerebral representation. Subjects complete this approximately every three hours during wake. Test scores are adjusted for practice and stimulus set effects, and z-transformed based on average and standard deviation across all tests taken. Speed across cognitive domains is calculated by averaging z-scores across the 10 tests. Higher scores reflect faster speed. The final measure is reported as the least square means of the z-score. Scores between -0.2 and +0.2 suggest no effect on speed (0=population mean). More negative scores suggest larger negative effects (i.e. scores between -0.2 to -0.5 mean slightly slower; -0.5 to -0.8 moderately slower; scores beyond -0.8 significantly slower). Greater positive scores suggest larger positive effects (i.e. scores between +0.2 to +0.5 mean slightly faster; +0.5 to +0.8 moderately faster; above +0.8 significantly faster).
Time frame
From Study Day 2 through Study Day 6 (to include each of the three conditions: ALC, CTRL, SD1&2).2
Cognition Test Battery Accuracy
A single variable representing accuracy across 10 Cognitive tasks that cover a range of cognitive domains with known cerebral representation. Test scores are adjusted for practice and stimulus set effects, and z-transformed based on average and standard deviation across all tests taken. Accuracy across cognitive domains is calculated by averaging z-scores across the 10 tests. Higher scores reflect better accuracy. The final measure is reported as the least square means of the z-score. Scores between -0.2 and +0.2 suggest no effect on accuracy (0=population mean). More negative scores suggest larger negative effects (i.e. scores between -0.2 to -0.5 mean slightly less accurate; -0.5 to -0.8 moderately less accurate; scores beyond -0.8 significantly less accurate). Greater positive scores suggest larger positive effects (i.e. scores between +0.2 to +0.5 mean slightly more accurate; +0.5 to +0.8 moderately more accurate; above +0.8 significantly more accurate).
Time frame
From Study Day 2 through Study Day 6 (to include each of the three conditions: ALC, CTRL, SD1&2).Sponsors and contacts
Click on the lead sponsor to view all of their trials.
University of Pennsylvania
Lead sponsor
Uniformed Services University of the Health Sciences
Collaborator
University of Florida
Collaborator
Cornell University/Weill Cornell Medical Center
Collaborator
National Aeronautics and Space Administration (NASA)
Collaborator
University of Nevada, Las Vegas
Collaborator
Loma Linda University
Collaborator
Source ClinicalTrials.gov