title: Plantar tactile perturbations enhance transfer of split-belt locomotor adaptation.
abstract: Patterns of human locomotion are highly adaptive and flexible and depend on the environmental context. Locomotor adaptation requires the use of multisensory information to perceive altered environmental dynamics and generate an appropriate movement pattern. In this study, we investigated the use of multisensory information during locomotor learning. Proprioceptive perturbations were induced by vibrating tactors, placed bilaterally over the plantar surfaces. Under these altered sensory conditions, participants were asked to perform a split-belt locomotor task representative of motor learning. Twenty healthy young participants were separated into two groups: no-tactors (NT) and tactors (TC). All participants performed an overground walking trial, followed by treadmill walking including 18 min of split-belt adaptation and an overground trial to determine transfer effects. Interlimb coordination was quantified by symmetry indices and analyzed using mixed repeated-measures ANOVAs. Both groups adapted to the locomotor task, indicated by significant reductions in gait symmetry during the split-belt task. No significant group differences in spatiotemporal and kinetic parameters were observed on the treadmill. However, significant group differences were observed overground. Step and swing time asymmetries learned on the split-belt treadmill were retained and decayed more slowly overground in the TC group whereas in NT, asymmetries were rapidly lost. These results suggest that tactile stimulation contributed to increased lower limb proprioceptive gain. High proprioceptive gain allows for more persistent overground after effects, at the cost of reduced adaptability. Such persistence may be utilized in populations displaying pathologic asymmetric gait by retraining a more symmetric pattern.
authors.affiliation: Biomechanics Research Building, School of Health, Physical Education and Recreation, University of Nebraska at Omaha, Omaha, NE, 68182-0214, USA. mmukherjee@unomaha.edu.
authors.forename: Mukul
authors.initials: M
authors.lastname: Mukherjee
authors.affiliation: Biomechanics Research Building, School of Health, Physical Education and Recreation, University of Nebraska at Omaha, Omaha, NE, 68182-0214, USA.
authors.forename: Diderik Jan A
authors.initials: DJ
authors.lastname: Eikema
authors.affiliation: Biomechanics Research Building, School of Health, Physical Education and Recreation, University of Nebraska at Omaha, Omaha, NE, 68182-0214, USA.
authors.forename: Jung Hung
authors.initials: JH
authors.lastname: Chien
authors.affiliation: Biomechanics Research Building, School of Health, Physical Education and Recreation, University of Nebraska at Omaha, Omaha, NE, 68182-0214, USA.
authors.forename: Sara A
authors.initials: SA
authors.lastname: Myers
authors.affiliation: Wyle Science, Technology and Engineering, NASA Johnson Space Center, Houston, TX, USA.
authors.forename: Melissa
authors.initials: M
authors.lastname: Scott-Pandorf
authors.affiliation: Neuroscience Laboratories, NASA Johnson Space Center, Houston, TX, USA.
authors.forename: Jacob J
authors.initials: JJ
authors.lastname: Bloomberg
authors.affiliation: Biomechanics Research Building, School of Health, Physical Education and Recreation, University of Nebraska at Omaha, Omaha, NE, 68182-0214, USA.|Department of Environmental, Agricultural and Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE, USA.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Stergiou
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D011434:Proprioception / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*; D014163:Transfer, Psychology / Q000502:physiology*; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Biomechanics; Gait; Motor learning; Perception; Sensation; Touch; Vibration