title: Motor imagery of gait: a new way to detect mild cognitive impairment?
abstract: OBJECTIVE
  1) To measure and compare the time required to perform (pTUG) and the time required to imagine (iTUG) the Timed Up & Go (TUG), and the time difference between these two tasks (i.e., TUG delta time) in older adults with cognitive decline (i.e., mild cognitive impairment (MCI) and mild-to-moderate Alzheimer disease and related disorders (ADRD)) and in cognitively healthy individuals (CHI); and 2) to examine any association between the TUG delta time and a cognitive status.
  
  
  METHODS
  Sixty-six participants (24 CHI, 23 individuals with MCI, and 19 individuals with ADRD) were recruited in this cross-sectional study. The mean and standard deviation of the pTUG and iTUG completion times and the TUG delta time, as well as age, gender, and Mini-Mental State Examination (MMSE) scores were used as outcomes. Participants were separated into three groups based on the tertilization of TUG delta time: lowest (<13.6%; n = 22; best performance), intermediate (13.6-52.2%; n = 22), and highest tertile (>52.2%; n = 22, worst performance).
  
  
  RESULTS
  Fewer CHI were in the group exhibiting the highest tertile of TUG delta time compared to individuals with lowest and intermediate TUG delta times (p = 0.013). Being in the highest tertile of the TUG delta time was associated with cognitive decline in the unadjusted model (p = 0.012 for MCI, and p = 0.021 for mild-to-moderate ADRD). In the multivariate models, this association remained significant only for individuals with MCI (p = 0.019 while adjusting for age and gender; p = 0.047 while adjusting for age, gender, and MMSE score; p = 0.012 for the stepwise backward model).
  
  
  CONCLUSIONS
  Our results provide the first evidence that motor imagery of gait may be used as a biomarker of MCI in older adults.
authors.affiliation: Department of Neuroscience, Division of Geriatric Medicine, Angers University Hospital, 49933 Angers cedex 9, France. olbeauchet@chu-angers.fr.
authors.forename: Olivier
authors.initials: O
authors.lastname: Beauchet
authors.forename: Cyrille P
authors.initials: CP
authors.lastname: Launay
authors.forename: Ervin
authors.initials: E
authors.lastname: Sejdić
authors.forename: Gilles
authors.initials: G
authors.lastname: Allali
authors.forename: Cédric
authors.initials: C
authors.lastname: Annweiler
mesh_terms: D000368:Aged; D060825:Cognitive Dysfunction / Q000175:diagnosis*; D003430:Cross-Sectional Studies; D005260:Female; D005684:Gait; D015577:Geriatric Assessment / Q000379:methods*; D006801:Humans; D007092:Imagination; D008297:Male; D009043:Motor Activity; D013995:Time
references.citation: Eur J Neurol. 2012 Jul;19(7):1023-9
references.pmid: 22339714
references.citation: Neuropsychiatr Dis Treat. 2008 Feb;4(1):155-60
references.pmid: 18728766
references.citation: J Gerontol A Biol Sci Med Sci. 2013 Apr;68(4):412-8
references.pmid: 22987797
references.citation: J Neural Transm (Vienna). 2008 Aug;115(8):1149-58
references.pmid: 18506392
references.citation: Gait Posture. 2008 Jan;27(1):156-9
references.pmid: 17291765
references.citation: J Nutr Health Aging. 2013 Mar;17(3):235-9
references.pmid: 23459976
references.citation: J Intern Med. 2004 Sep;256(3):240-6
references.pmid: 15324367
references.citation: Neuroimage. 2004 Aug;22(4):1722-31
references.pmid: 15275928
references.citation: Neurobiol Aging. 2012 Jun;33(6):1073-84
references.pmid: 21051105
references.citation: Gait Posture. 2007 Oct;26(4):572-6
references.pmid: 17344044
references.citation: J Psychiatr Res. 1975 Nov;12(3):189-98
references.pmid: 1202204
references.citation: J Am Geriatr Soc. 1991 Feb;39(2):142-8
references.pmid: 1991946
references.citation: Psychiatry Res. 2012 Aug 15;198(3):366-70
references.pmid: 22445069
references.citation: Neurology. 2000 Dec 12;55(11):1621-6
references.pmid: 11113214
references.citation: J Neural Transm (Vienna). 2013 Jul;120(7):1083-92
references.pmid: 23196981
references.citation: J Consult Psychol. 1958 Dec;22(6):469-74
references.pmid: 13611107
references.citation: Gerontology. 2009;55(6):702-6
references.pmid: 19713694
references.citation: Lancet Neurol. 2010 Nov;9(11):1118-27
references.pmid: 20934914
references.citation: J Neural Transm (Vienna). 2010 Oct;117(10):1171-6
references.pmid: 20809070
references.citation: J Gerontol A Biol Sci Med Sci. 2014 Nov;69(11):1389-98
references.pmid: 24368777
references.citation: Neuropsychologia. 1995 Nov;33(11):1419-32
references.pmid: 8584178
references.citation: Neurology. 2006 Aug 8;67(3):461-6
references.pmid: 16894108
references.citation: Am J Psychiatry. 1984 Nov;141(11):1356-64
references.pmid: 6496779
references.citation: Mov Disord. 2010 Apr 30;25(6):731-7
references.pmid: 20175202
references.citation: J Neurol Sci. 2010 Jul 15;294(1-2):102-6
references.pmid: 20444477
references.citation: Neurology. 1984 Jul;34(7):939-44
references.pmid: 6610841
references.citation: Age Ageing. 1997 May;26(3):217-21
references.pmid: 9223718
references.citation: Eur Neurol. 2012;67(2):116-20
references.pmid: 22236807
references.citation: Curr Opin Neurobiol. 1995 Dec;5(6):727-32
references.pmid: 8805419
references.citation: Neurology. 1988 Jun;38(6):900-3
references.pmid: 3368071