@article{HarrisJenkinHerpers2022,
  author    = {Laurence R. Harris and Michael Jenkin and Rainer Herpers},
  title     = {Long-duration head down bed rest as an analog of microgravity: Effects on the static perception of upright},
  series   = {Journal of Vestibular Research},
  volume    = {32},
  number    = {4},
  publisher = {IOS Press},
  issn      = {1878-6464},
  doi       = {10.3233/VES-210016},
  url       = {https://nbn-resolving.org/urn:nbn:de:hbz:1044-opus-59877},
  pages     = {325 -- 340},
  year      = {2022},
  abstract  = {BACKGROUND: Humans demonstrate many physiological changes in microgravity for which long-duration head down bed rest (HDBR) is a reliable analog. However, information on how HDBR affects sensory processing is lacking. OBJECTIVE: We previously showed [25] that microgravity alters the weighting applied to visual cues in determining the perceptual upright (PU), an effect that lasts long after return. Does long-duration HDBR have comparable effects? METHODS: We assessed static spatial orientation using the luminous line test (subjective visual vertical, SVV) and the oriented character recognition test (PU) before, during and after 21 days of 6° HDBR in 10 participants. Methods were essentially identical as previously used in orbit [25]. RESULTS: Overall, HDBR had no effect on the reliance on visual relative to body cues in determining the PU. However, when considering the three critical time points (pre-bed rest, end of bed rest, and 14 days post-bed rest) there was a significant decrease in reliance on visual relative to body cues, as found in microgravity. The ratio had an average time constant of 7.28 days and returned to pre-bed-rest levels within 14 days. The SVV was unaffected. CONCLUSIONS: We conclude that bed rest can be a useful analog for the study of the perception of static self-orientation during long-term exposure to microgravity. More detailed work on the precise time course of our effects is needed in both bed rest and microgravity conditions.},
  language  = {en}
}