Spaceflight Effects on Neurocognitive Performance: Extent, Longevity, and Neural Bases (NeuroMapping) - 12.03.13
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This research is being conducted to identify if there are any changes in brain structure, function, and network integrity as well as human motor control, spatial processing and multi-task performance abilities as a function of long-duration spaceflight. It will also determine how long it would take for the human body / brain to recover from such adaptations. This research will help generate relationships between structural and functional brain changes, correlated to human performance over time.
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OpNom: NeuroMappingPrincipal Investigator(s)
Johnson Space Center, Human Research Program, Houston, TX, United States
National Aeronautics and Space Administration (NASA)Sponsoring Organization
Human Exploration and Operations Mission Directorate (HEOMD)Research Benefits
Earth Benefits, Scientific Discovery, Space ExplorationISS Expedition Duration:
March 2014 - September 2014Expeditions Assigned
39/40,41/42,43/44Previous ISS Missions
- This study is needed to assess changes in elemental neurocognitive functions such as perception, motor control, memory, attention, and executive function following long duration spaceflight using both behavioral assessments and brain imaging technologies such as functional MRI. We propose to perform structural and functional MR brain imaging to identify the relationship between changes in crewmember neurocognitive function, neural structural alterations and its impact on indices of cognitive, sensory, and motor function in a neuroanatomically selective fashion during and following a six month International Space Station mission.
- Our interdisciplinary approach utilizes cutting edge neuroimaging techniques and a broad ranging battery of sensory, motor, and cognitive assessments that will be conducted pre flight, during flight, and post flight to investigate neuroplastic and maladaptive brain changes in crewmembers following long duration spaceflight. Success in this endeavor would 1) result in identification of the underlying neural mechanisms and operational risks of spaceflight-induced changes in behavior, and 2) identify whether a return to normative behavioral function following re-adaptation to Earth’s gravitational environment is associated with a restitution of brain structure and function or instead is supported by substitution with compensatory brain processes.
- The results of this project will have relevance not only to understanding the effects of spaceflight on the human brain and behavior, but also for delineating the capacity of the brain to remodel in response to exposure to microgravity, and how long it may take to recover as a result after a long duration space flight. As such, the results should prove informative for understanding the neural mechanisms of rehabilitation and adaptive behavioral change. This could have direct impacts on the designing of targeted cognitive and behavioral countermeasures for upcoming human spaceflight exploration missions in the future.
During spaceflight, the control of movement is altered to account for the fundamental change in gravity. This can lead to motion disturbances and difficulty controlling motion following transitions in gravity levels (e.g., transition to Earth, lunar or Martian surfaces). Spaceflight has also been anecdotally reported to affect cognition. This investigation proposes to perform structural and functional magnetic resonance brain imaging (MRI and FMRI) to identify the relationship between changes in crewmember neurocognitive function and neural structural alterations following a six month International Space Station (ISS) mission. Our interdisciplinary approach utilizes cutting-edge neuroimaging techniques and a broad ranging battery of sensory, motor, and cognitive assessments that will be conducted pre-flight, during flight, and post-flight to investigate neuroplastic and maladaptive brain changes in crewmembers following long-duration spaceflight. Success in this endeavor would result in identification of the underlying neural mechanisms and operational risks of spaceflight-induced changes in behavior, and also identify whether a return to normative behavioral function following re-adaptation to Earth's gravitational environment is associated with a restitution of brain structure and function or instead is supported by substitution with compensatory brain processes.
Each BDC session (pre- and post-flight) will consist of non-invasive brain structural and functional imaging tests in a magnetic resonance imaging (MRI) scanner (neuroimaging assessment) as well as several laboratory tests of sensory, motor, and cognitive function (behavioral assessment). The details of the tests are listed below.
Pre- and Post-flight Behavioral Assessment Tests include:
Assessments of spatial transformation:
- Card rotation: This is a timed pencil and paper test requiring participants to mentally rotate target shapes and indicate whether they are the same or different from a standard shape
- Mental rotation: Subjects need to memorize and subsequently identify a match to a re-oriented 3D cube assemblage.
- Rod and Frame test: Subjects align a rod to vertical within a tilted frame
Assessments of processing speed:
- Digit-symbol substitution task: This is a timed pencil and paper test requiring participants to decode shapes into numbers using a presented key
Assessments of motor control:
- Functional Mobility Test : Navigate obstacle course on a medium density foam surface.
- Bimanual Motor Control: Place 25 keyed pegs into their corresponding slots using both hands while seated.
Assessments of vestibular function:
- Vestibular Evoked Myogenic Potential (VEMP) test : A surface potential in response to otolith (auditory) stimulation is recorded from the muscle under the eyes (ocular VEMP) and from neck muscle while it is being contracted (colic VEMP).
- Vestibular contribution to Postural Stability: Maintain balance on sway-referenced support surface with eyes closed. This test will be performed with and without head movements.
Passive structural and functional scans (during which participants lay still and do not perform a task)
- Structural MRI scan: High-resolution anatomical images covering the whole brain including the cerebellum
- Resting state functional connectivity MRI: Strength of communications between “hubs” in the brain’s networks
- Diffusion weighted imaging: Quantify large white matter pathways in the brain and calculate their structural integrity specifically the corticospinal tract connecting motor brain regions and the spinal cord, in addition to other pathways.
Active structural and functional scans (during which participants perform a task)
- fMRI during auditory click-induced VEMP: Identify brain regions processing vestibular information which undergo plasticity as a function of microgravity exposure. Subjects will hear auditory clicks.
- fMRI during manual sensorimotor adaptation task: Identify brain regions supporting visuomotor plasticity. Subjects will move cursor from center to target locations using a joystick under normal or rotated visual feedback.
- fMRI during spatial working memory task: Identify brain regions engaged in spatial cognition. Subjects will indicate correct spatial rotation of a triad target set using button clicks.
- fMRI during dual tasking: Identify brain regions in dual task. Subjects will press buttons matched to a psudo-random pattern of highlighted positions of stimulus boxes while also monitoring for the occurrence of a target color.
In-flight Behavioral Assessments include:
The Behavioral assessments are a subset of the pre / post flight tests and include: mental rotation, sensorimotor adaptation, and motor-cognitive dual tasking
- Mental rotation task: Subjects need to memorize and subsequently identify a match to a re-oriented 3D cube assemblage.
- Sensorimotor adaptation task: Subjects will move cursor from center to target locations using a joystick under normal or rotated visual feedback.
- Dual tasking: Subjects will press buttons matched to a pseudo-random pattern of highlighted positions of stimulus boxes while also monitoring for the occurrence of a target color.
The crew will use and operate:
- ESA Control Pad
- HRF PC
- NeuroMapping Experiment Unique Software
- Tethers, foot loops
Changes in brain structure and function may play a direct role in spaceflight-associated sensorimotor and cognitive dual task deficits, and may further impact the long-term health of astronauts. NASA crewmembers may be at risk if substantial volumetric degeneration and/or functional reorganization in the brain occur during spaceflight.
Completion of this study will result in identification of the underlying neural mechanisms and operational risks of spaceflight-induced changes in behavior, and will identify whether a return to normative behavioral function following re-adaptation to Earth’s gravitational environment is associated with a restitution of brain structure and function or instead is supported by substitution with compensatory brain processes. Identification of neurocognitive changes occurring as a function of spaceflight is the first step towards development of targeted countermeasures, which could include programs such as targeted neurocognitive and sensorimotor adaptability training.
This study integrates high priority research topics in NASA’s Human Research Program (HRP) from the Behavioral Health and Performance (BHP) Element, Space Human Factors and Habitability (SHFH) Element and the Human Health and Countermeasures (HHC) Element (Sensorimotor Discipline).
This proposal addresses the following BHP Risk and Gaps: Risk of Adverse Behavioral Conditions and Psychiatric Disorders
- IRP GAP BMed3: What aspects, if any, of cognitive performance change in-flight? If there are changes, do they persist post mission? If so, for how long?
- IRP GAP BMed4: What are the most effective methods for detecting and assessing cognitive performance during exploration missions?
This proposal addresses the following SHFH Risk and Gap: Risk of Error Due To Inadequate Information
- IRP Gap: SHFE 126.96.36.199.2.1: Can crewmember spatiomotor abilities be more accurately predicted and countermeasures and training techniques developed to mitigate spatial disorientation during spaceflight?
This proposal addresses the following HHC Risk and Gap: Risk of Impaired Control of Spacecraft, Associated Systems and Immediate Vehicle Egress Due to Vestibular/Sensorimotor Alterations Associated with Space Flight
- IRP Gap SM26: Does exposure to long-duration spaceflight lead to neural structural alterations and does this remodeling impact cognitive and functional performance?
The results of this project will have relevance not only to understanding the effects of spaceflight on the human brain and behavior, but also for delineating the capacity of the brain to remodel in response to adaptive stimuli. As such, the results should prove informative for understanding the neural mechanisms associated with adaptive behavioral change and the rehabilitation of these changes during recovery periods.
- This experiment requires 13 subjects.
- Pre-flight sessions consists of behavioral and neuroimaging tests and will occur at L-180 (+/- 60 days) and L-60 days. Post-flight sessions will occur four times at R+1-5, R+30, R+90, and R+180 days. The preference is to perform both Behavioral and Neuroimaging tests on the same day. However, if both tests cannot be accommodated on the same day, the Behavioral Assessment Tests will precede the Neuroimaging Tests. The Neuroimaging Tests may be performed up to, but no more than, 2 days following the Behavioral Assessment Testing for each session. There should be at least 20 days in between the L-180 and L-60 BDC sessions and the first post-flight BDC session needs to be completed by R+5 for both the Behavioral and Neuroimaging Assessment Tests.
- In-flight tests will be performed on FD30, FD90, and FD150 (all sessions are ±10 days) and can be scheduled at any time of day, but should be consistent throughout the mission. During the in-flight sessions, the body should be tethered at the waist and with foot loops to maintain a ‘seated’ posture. The Control Pad should be adjacent to and in the same plane as the HRF PC keyboard. Subject will be oriented facing the screen, with the screen at eye level. One segment of the in-flight session will be performed in a ‘free floating’ position using the tether at the waist, but no foot loops. For this segment, the gamepad will still be in the same plane as the laptop keyboard while the subject faces the screen, with the screen at eye level. Photography of the experiment should be captured at least once per subject during the mission. Data downlink should occur at least one week prior to next scheduled session. This may be scheduled when the HRF Rack is already on for another activity (to save a console session).
In-flight, a subset of behavioral assessment tests will be performed to complement the pre- and post-flight testing, including a mental rotation test, dual task test, and a joystick-based sensorimotor adaptation test. Three (3) in-flight sessions are required on FDs 30, 90, and 150 (flexibility +/- 10 days). Each in-flight session will require 40 minutes of crew time. In-flight sessions will utilize the existing HRF PCs and the ESA Control Pad. Photos will be taken for documentary purposes, one session per subject (10 minutes of crew time). Data should be downlinked to the ground and delivered to the principal investigator (PI) prior to next scheduled session. Real-time downlink of data is not required for this study.