Does vibrotactile biofeedback for postural control interfere with cognitive processes?

Journal of NeuroEngineering and Rehabilitation, vol. 21, pp. 184

Abstract

BACKGROUND: Directional vibrotactile biofeedback for balance control can be instructed in the form of Repulsive (to move in the opposite direction of vibrations) or Attractive (to move in the direction of vibrations) stimulus encodings. However, which of these encodings is less cognitively demanding and poses less interference with high-level cognitive processes of conflict resolution remains unresolved. METHODS: In two between-subject studies with 30 (16 females) and 35 (23 females) healthy young adults, respectively, we investigated the cognitive load of Attractive and Repulsive vibrotactile biofeedback on 1) working memory (Study I) and 2) cognitive conflict resolution (Study II). Both studies also examined the effectiveness of both feedback stimulus encodings on balance control during quiet standing with eyes closed. RESULTS: Both Attractive and Repulsive vibrotactile biofeedback increased balance stability (reduced trunk sway variability) in both the working memory and the conflict resolution study (Study I and II, respectively) with a greater increase of stability for the Repulsive encoding during multitasking demanding cognitive conflict resolution (Study II). Cognitive costs, measured in terms of the Linear Integrated Speed-Accuracy Score (LISAS), were greater for the Attractive encoding during multitasking with working memory demands. When cognitive conflict resolution was required as a secondary cognitive task, both stimulus encodings increased cognitive costs equally. CONCLUSIONS: The effects of instructed Repulsive and Attractive stimulus encodings for the response-related interpretation of vibrotactile biofeedback of body sway were contrasted with respect to cognitive processing demands and balance stabilisation benefits. Both encodings improved balance stability but at certain cognitive costs. Regarding interference with specific high-level cognitive processes, however, a distinction has to be made between both encodings. Repulsive feedback encoding seems to cause less cognitive costs on working memory load and slightly greater stabilisation when cognitive conflict resolution is required. These results are discussed in the context of the known benefits of avoidance actions on cognitive control.

Authors 5

1. Katrin Hanna Schulleri corresponding

   Technical University of Munich

   Affiliation as printed

   Human-centered Assistive Robotics, Technical University of Munich, Karlstraße, 80333, Munich, Bavaria, Germany. katrin.schulleri@tum.de

   Human-centered Assistive Robotics, Technical University of Munich, Karlstraße, 80333, Munich, Bavaria, Germany

2. Farbod Feizian

   Technical University of Munich

   Affiliation as printed

   Human-centered Assistive Robotics, Technical University of Munich, Karlstraße, 80333, Munich, Bavaria, Germany

3. Martina Steinböck

   Schön Klinik Bad Aibling · Technical University of Munich

   Affiliation as printed

   Department Health and Sport Sciences, Technical University of Munich, Georg-Brauchle-Ring, 80992, Munich, Bavaria, Germany

   Department of Neurology, Research Group, Schoen Clinic Bad Aibling, Kolbermoorer Straße, 83043, Bad Aibling, Bavaria, Germany

4. Dongheui Lee

   TU Wien · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

   Affiliation as printed

   Autonomous Systems, Technische Universität Wien, Gusshausstrasse, 1040, Vienna, Austria

   Institute of Robotics and Mechatronics, German Aerospace Center (DLR), Münchener Straße, 82234, Wessling, Bavaria, Germany

5. Leif Johannsen Aachen Institute of Psychology

   Technical University of Munich · RWTH Aachen University

   Affiliation as printed

   Department Health and Sport Sciences, Technical University of Munich, Georg-Brauchle-Ring, 80992, Munich, Bavaria, Germany

   Institute of Psychology, RWTH Aachen University, Jaegerstrasse 17/19, 52066, Aachen, Germany