Long-duration head down bed rest as an analog of microgravity: Effects on the static perception of upright.

Publisher: IOS Press Country of Publication: Netherlands NLM ID: 9104163 Publication Model: Print Cited Medium: Internet ISSN: 1878-6464 (Electronic) Linking ISSN: 09574271 NLM ISO Abbreviation: J Vestib Res Subsets: MEDLINE

Publication: 2001- : Amsterdam : IOS Press
Original Publication: New York : Pergamon Press, c1990-

Bed Rest* ; Weightlessness*; Head-Down Tilt/physiology ; Humans ; Perception ; Time Factors ; Weightlessness Simulation

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.

Neurosci Lett. 2012 Oct 31;529(1):7-11. (PMID: 22999922)
J Vis. 2013 Feb 01;13(2):3. (PMID: 23378132)
Exp Brain Res. 2001 Jun;138(4):410-8. (PMID: 11465738)
PLoS One. 2015 Dec 30;10(12):e0145528. (PMID: 26716835)
J Musculoskelet Neuronal Interact. 2020 Mar 3;20(1):101-113. (PMID: 32131374)
Front Physiol. 2020 Jun 23;11:716. (PMID: 32655420)
Adv Space Res. 1986;6(12):171-4. (PMID: 11537818)
Ann N Y Acad Sci. 1999 May 28;871:379-83. (PMID: 10372086)
Naturwissenschaften. 1983 Jun;70(6):272-81. (PMID: 6877388)
J Vestib Res. 2007;17(5-6):209-15. (PMID: 18626132)
J Neurophysiol. 2008 May;99(5):2264-80. (PMID: 18337369)
J Neurosci. 2011 Apr 6;31(14):5365-77. (PMID: 21471371)
Nat Neurosci. 1998 May;1(1):15-6. (PMID: 10195102)
Brain Res Brain Res Rev. 1998 Nov;28(1-2):185-93. (PMID: 9795210)
Nature. 1999 Apr 15;398(6728):615-8. (PMID: 10217143)
Front Neurol. 2019 Apr 03;10:172. (PMID: 31001184)
Aerosp Med. 1973 May;44(5):484-7. (PMID: 4710520)
Eur J Neurosci. 2010 May;31(10):1899-907. (PMID: 20584195)
J Neurophysiol. 2009 Mar;101(3):1321-33. (PMID: 19118112)
J Neuroophthalmol. 2016 Mar;36(1):85-91. (PMID: 26828842)
Eur J Appl Physiol. 2007 Sep;101(2):143-94. (PMID: 17661073)
NPJ Microgravity. 2017 Jan 12;3:3. (PMID: 28649625)
Behav Brain Res. 1998 Jun;93(1-2):185-90. (PMID: 9659999)
J Vestib Res. 2010;20(1):45-51. (PMID: 20555166)
Bone. 2007 Dec;41(6):973-8. (PMID: 17931994)
Aviat Space Environ Med. 1983 Nov;54(11):1001-4. (PMID: 6651724)
Adv Otorhinolaryngol. 1988;42:24-30. (PMID: 3265015)
Brain Res Brain Res Rev. 1998 Nov;28(1-2):102-17. (PMID: 9795167)
Exp Brain Res. 2001 Apr;137(3-4):323-35. (PMID: 11355379)
Exp Brain Res. 2010 May;202(3):649-59. (PMID: 20135100)
Aviat Space Environ Med. 1985 Jun;56(6):601-6. (PMID: 3874622)
PLoS One. 2018 Oct 11;13(10):e0205515. (PMID: 30308004)
Aviat Space Environ Med. 2010 Sep;81(9):819-24. (PMID: 20824987)
Exp Brain Res. 2006 Sep;173(4):612-22. (PMID: 16550392)
Exp Brain Res. 2010 Aug;204(4):617-22. (PMID: 20535455)
Aviat Space Environ Med. 1987 Sep;58(9 Pt 2):A159-63. (PMID: 3499892)
PLoS One. 2014 Oct 29;9(10):e111107. (PMID: 25354042)
J Appl Physiol (1985). 2005 Jul;99(1):134-40. (PMID: 15691900)
Biol Psychol. 1996 Jan 5;42(1-2):53-74. (PMID: 8770370)
Stroke. 2002 Sep;33(9):2247-53. (PMID: 12215595)
J Vis. 2007 May 23;7(7):5.1-24. (PMID: 17685801)
Acta Psychol (Amst). 1986 Dec;63(1-3):63-85. (PMID: 3591446)
J Neurol Neurosurg Psychiatry. 1971 Oct;34(5):489-95. (PMID: 4941476)
Nature. 2002 Jan 24;415(6870):429-33. (PMID: 11807554)

Keywords: HDBR; Human orientation perception; head down bed rest; perceptual upright; space flight analog; subjective visual vertical

Date Created: 20211101 Date Completed: 20220726 Latest Revision: 20220917

20231215

PMC9398091

10.3233/VES-210016

34719448