title: Study protocol to examine the effects of spaceflight and a spaceflight analog on neurocognitive performance: extent, longevity, and neural bases.
abstract: BACKGROUND
  Long duration spaceflight (i.e., 22 days or longer) has been associated with changes in sensorimotor systems, resulting in difficulties that astronauts experience with posture control, locomotion, and manual control. The microgravity environment is an important causal factor for spaceflight induced sensorimotor changes. Whether spaceflight also affects other central nervous system functions such as cognition is yet largely unknown, but of importance in consideration of the health and performance of crewmembers both in- and post-flight. We are therefore conducting a controlled prospective longitudinal study to investigate the effects of spaceflight on the extent, longevity and neural bases of sensorimotor and cognitive performance changes. Here we present the protocol of our study.
  
  
  METHODS
  This study includes three groups (astronauts, bed rest subjects, ground-based control subjects) for which each the design is single group with repeated measures. The effects of spaceflight on the brain will be investigated in astronauts who will be assessed at two time points pre-, at three time points during-, and at four time points following a spaceflight mission of six months. To parse out the effect of microgravity from the overall effects of spaceflight, we investigate the effects of seventy days head-down tilted bed rest. Bed rest subjects will be assessed at two time points before-, two time points during-, and three time points post-bed rest. A third group of ground based controls will be measured at four time points to assess reliability of our measures over time. For all participants and at all time points, except in flight, measures of neurocognitive performance, fine motor control, gait, balance, structural MRI (T1, DTI), task fMRI, and functional connectivity MRI will be obtained. In flight, astronauts will complete some of the tasks that they complete pre- and post flight, including tasks measuring spatial working memory, sensorimotor adaptation, and fine motor performance. Potential changes over time and associations between cognition, motor-behavior, and brain structure and function will be analyzed.
  
  
  CONCLUSIONS
  This study explores how spaceflight induced brain changes impact functional performance. This understanding could aid in the design of targeted countermeasures to mitigate the negative effects of long-duration spaceflight.
authors.forename: Vincent
authors.initials: V
authors.lastname: Koppelmans
authors.forename: Burak
authors.initials: B
authors.lastname: Erdeniz
authors.forename: Yiri E
authors.initials: YE
authors.lastname: De Dios
authors.forename: Scott J
authors.initials: SJ
authors.lastname: Wood
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Reuter-Lorenz
authors.forename: Igor
authors.initials: I
authors.lastname: Kofman
authors.forename: Jacob J
authors.initials: JJ
authors.lastname: Bloomberg
authors.forename: Ajitkumar P
authors.initials: AP
authors.lastname: Mulavara
authors.affiliation: School of Kinesiology, University of Michigan, Ann Arbor MI, USA. rseidler@umich.edu.
authors.forename: Rachael D
authors.initials: RD
authors.lastname: Seidler
mesh_terms: D000293:Adolescent; D000328:Adult; D000337:Aerospace Medicine; D018480:Astronauts / Q000523:psychology; D001510:Bed Rest; D001921:Brain / Q000098:blood supply / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008124:Locomotion; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term; D055806:Microvessels / Q000502:physiology; D008875:Middle Aged; D009043:Motor Activity; D010100:Oxygen / Q000097:blood; D011187:Posture; D011597:Psychomotor Performance; D012307:Risk Factors; D013026:Space Flight; D013997:Time Factors; D058585:Vestibular Evoked Myogenic Potentials; D014893:Weightlessness; D055815:Young Adult
chemical_list: D010100:Oxygen