title: The specificity of practice hypothesis in goal-directed movements: visual dominance or proprioception neglect?
abstract: The study aimed to examine whether modifying the proprioceptive feedback usually associated with a specific movement would decrease the dominance of visual feedback and/or decrease, which appears to be the neglect of proprioceptive feedback in ensuring the accuracy of goal-directed movements. We used a leg positioning recall task and measured the recall error after 15 and 165 acquisition trials performed with both vision and proprioception or proprioception only, under either a normal or a modified proprioception condition (i.e., with a 1-kg load attached to the participants' ankle). Participant learning was evaluated in transfer with proprioception only. In support of the specificity of practice hypothesis, the recall errors in acquisition were significantly smaller when practice occurred with both vision and proprioception, in either the loaded or the unloaded leg condition, and they increased significantly in transfer when vision was withdrawn. An important finding of the study highlighted that withdrawing vision after 165 acquisition trials had less deleterious effects on the recall errors when practice occurred under the loaded leg condition. Under that modified condition, recall errors in transfer were similar when practice occurred with and without vision, whereas larger errors were observed following practice with vision under the normal proprioceptive condition. Overall, these results highlighted the dominance of vision in ensuring accurate leg positioning recall and revealed that the dominance of vision is such that the processing of proprioceptive feedback may be neglected. Importantly, modifying the proprioceptive feedback has the advantage of reducing what appears to be the neglect of proprioceptive information when movement execution occurs in a visuo-proprioceptive context. Practical considerations for rehabilitation are discussed at the end of the manuscript.
authors.affiliation: Université de Poitiers, Centre de Recherches sur la Cognition et l'Apprentissage, CeRCA, CNRS/UMR 7295, 5 rue Théodore Lefebvre, 86000, Poitiers, France. lucette.toussaint@univ-poitiers.fr.
authors.forename: Lucette
authors.initials: L
authors.lastname: Toussaint
authors.affiliation: Université de Poitiers, Centre de Recherches sur la Cognition et l'Apprentissage, CeRCA, CNRS/UMR 7295, 5 rue Théodore Lefebvre, 86000, Poitiers, France.
authors.forename: Aurore
authors.initials: A
authors.lastname: Meugnot
authors.affiliation: CNRS, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (UMR 5287), Université de Bordeaux, Bordeaux, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Badets
authors.affiliation: Maison des Sciences de l'Homme et de la Société (MSHS, USR 3565), Poitiers, France.
authors.forename: David
authors.initials: D
authors.lastname: Chesnet
authors.affiliation: Département de kinésiologie, Université de Montréal, Quebec, Canada.
authors.forename: Luc
authors.initials: L
authors.lastname: Proteau
mesh_terms: D000328:Adult; D005260:Female; D006040:Goals; D006801:Humans; D008297:Male; D011434:Proprioception / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D013647:Task Performance and Analysis; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult