Seeing Is Believing: Effects of Visual Contextual Cues on Learning and Transfer of Locomotor Adaptation

Johns Hopkins University, Baltimore, Maryland, United States
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.75). 12/2010; 30(50):17015-22. DOI: 10.1523/JNEUROSCI.4205-10.2010
Source: PubMed

ABSTRACT Devices such as robots or treadmills are often used to drive motor learning because they can create novel physical environments. However, the learning (i.e., adaptation) acquired on these devices only partially generalizes to natural movements. What determines the specificity of motor learning, and can this be reliably made more general? Here we investigated the effect of visual cues on the specificity of split-belt walking adaptation. We systematically removed vision to eliminate the visual-proprioceptive mismatch that is a salient cue specific to treadmills: vision indicates that we are not moving while leg proprioception indicates that we are. We evaluated the adaptation of temporal and spatial features of gait (i.e., timing and location of foot landing), their transfer to walking over ground, and washout of adaptation when subjects returned to the treadmill. Removing vision during both training (i.e., on the treadmill) and testing (i.e., over ground) strongly improved the transfer of treadmill adaptation to natural walking. Removing vision only during training increased transfer of temporal adaptation, whereas removing vision only during testing increased the transfer of spatial adaptation. This dissociation reveals differences in adaptive mechanisms for temporal and spatial features of walking. Finally training without vision increased the amount that was learned and was linked to the variability in the behavior during adaptation. In conclusion, contextual cues can be manipulated to modulate the magnitude, transfer, and washout of device-induced learning in humans. These results bring us closer to our ultimate goal of developing rehabilitation strategies that improve movements beyond the clinical setting.

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Available from: Gelsy Torres-Oviedo, May 20, 2015
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    • "Subjects also exploit 90 redundancy between the local variables stride length and stride time to maintain constant speed during 91 steady-state treadmill walking (Dingwell et al. 2010). Locomotor adaptation research has typically 92 focused on the changes occurring in limb-level or interlimb parameters like stride length, stride time and 93 ground reaction force (Finley et al. 2013; Dingwell et al. 2010; Torres-Oviedo and Bastian 2010; 94 Vasudevan and Bastian 2010; Dingwell et al. 1996). These global changes have a direct bearing on 95 locomotor performance and must often be modified according to the experimental paradigm. "
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