title: When standing on a moving support, cutaneous inputs provide sufficient information to plan the anticipatory postural adjustments for gait initiation.
abstract: Gait initiation is preceded by initial postural adjustments whose goal is to set up the condition required for the execution of the focal stepping movement. For instance, the step is preceded by a shift of the body's center of mass towards the stance foot unloading the stepping leg. This displacement is produced by exerting forces on the ground (i.e., thrust) while the body is still motionless. The purpose of this study was to identify whether the mere cutaneous inputs from the feet soles evoked by a lateral translation of the support could be used to scale the initial postural adjustments. Participants stood with their eyes closed on a force platform that could be moved laterally with a low acceleration (between 0.14 m/s(2) and 0.30 m/s(2)) to reach a constant velocity of 0.02 m/s. This translation resulted in a change in the somatosensory cues from the feet soles without modifying vestibular inputs. Participants were instructed to produce a step with the right foot as soon as they felt the platform start to move (on either side) or heard an auditory cue. In the latter case, the platform stayed stationary. We found that the thrust duration was lengthened when the platform moved towards the supporting foot. In this condition, the cutaneous stimulation provided information related to a body shift towards the stepping leg. This increased thrust duration likely helped overcoming the non-functional body shift perceived towards the stepping leg. This result highlights the accuracy with which the actual standing position can be determined from foot sole cutaneous cues in the absence of visual and vestibular or proprioceptive inputs.
authors: Cognitive Neurosciences Laboratory, Aix-Marseille University, CNRS, Marseille, France. laurence.mouchnino@univ-amu.fr
authors: Laurence
authors: L
authors: Mouchnino
authors: Jean
authors: J
authors: Blouin
mesh_terms: D000054:Acceleration; D000328:Adult; D003463:Cues; D004576:Electromyography; D005528:Foot / Q000502:physiology*; D005684:Gait / Q000502:physiology*; D006801:Humans; D009068:Movement / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D011434:Proprioception / Q000502:physiology*; D014722:Vestibule, Labyrinth / Q000502:physiology; D014796:Visual Perception / Q000502:physiology
references: J Biomech. 2002 Oct;35(10):1307-13
references: 12231276
references: J Neurophysiol. 1994 Dec;72(6):2892-902
references: 7897497
references: Exp Brain Res. 1998 Mar;119(1):73-84
references: 9521538
references: J Neurophysiol. 2013 Feb;109(3):839-50
references: 23155170
references: J Cogn Neurosci. 1999 Sep;11(5):551-9
references: 10511643
references: J Neurophysiol. 2007 Jun;97(6):4368-79
references: 17460098
references: J Neurophysiol. 1995 Mar;73(3):1181-91
references: 7608764
references: Exp Brain Res. 1990;79(2):319-24
references: 2323379
references: Clin Biomech (Bristol, Avon). 2001 Nov;16(9):719-27
references: 11714548
references: Brain Res Bull. 1996;40(5-6):443-7; discussion 448-9
references: 8886372
references: Neurosci Lett. 2002 May 3;323(3):167-70
references: 11959411
references: J Neurophysiol. 2003 Dec;90(6):3640-53
references: 12944535
references: Exp Brain Res. 2002 Mar;143(1):100-5
references: 11907695
references: Exp Brain Res. 2001 Nov;141(1):110-20
references: 11685415
references: Neuroreport. 1999 Aug 20;10(12):2457-60
references: 10574351
references: Neurosci Lett. 1998 Feb 13;242(2):61-4
references: 9533394
references: Cereb Cortex. 2009 Sep;19(9):2106-13
references: 19126799
references: J Physiol. 1994 Jul 1;478 ( Pt 1):173-86
references: 7965833
references: Lancet. 2013 Jan 5;381(9860):47-54
references: 23083889
references: Neuroreport. 1998 Oct 5;9(14):3247-52
references: 9831459
references: J Neurophysiol. 1975 May;38(3):539-59
references: 1127456
references: J Neurophysiol. 2006 Sep;96(3):1664-75
references: 16775211
references: Nat Neurosci. 2006 Jan;9(1):26-7
references: 16311591
references: Exp Brain Res. 1994;101(1):159-64
references: 7843295
references: Mov Disord. 2007 Jan;22(1):20-7
references: 17089421
references: J Physiol. 2002 Feb 1;538(Pt 3):995-1002
references: 11826182
references: Neuroscience. 2008 Aug 26;155(3):640-8
references: 18620030
references: J Neurophysiol. 2009 Jun;101(6):2751-61
references: 19321638
references: J Neurol Phys Ther. 2009 Jun;33(2):88-95
references: 19556917
references: Clin Biomech (Bristol, Avon). 2012 Jan;27(1):46-51
references: 21864955
references: Gait Posture. 2012 Apr;35(4):616-20
references: 22243988
references: Phys Ther. 2007 Feb;87(2):193-207
references: 17244695
references: J Mot Behav. 1991 Dec;23(4):235-40
references: 14766505
references: J Neurophysiol. 2003 Dec;90(6):3625-39
references: 12944536
references: Exp Brain Res. 2006 Sep;174(1):19-28
references: 16544134