title: The effects of attractive vs. repulsive instructional cuing on balance performance.
abstract: BACKGROUND
  Torso-based vibrotactile feedback has been shown to improve postural performance during quiet and perturbed stance in healthy young and older adults and individuals with balance impairments. These systems typically include tactors distributed around the torso that are activated when body motion exceeds a predefined threshold. Users are instructed to "move away from the vibration". However, recent studies have shown that in the absence of instructions, vibrotactile stimulation induces small (~1°) non-volitional responses in the direction of its application location. It was hypothesized that an attractive cuing strategy (i.e., "move toward the vibration") could improve postural performance by leveraging this natural tendency.
  
  
  RESULTS
  Eight healthy older adults participated in two non-consecutive days of computerized dynamic posturography testing while wearing a vibrotactile feedback system comprised of an inertial measurement unit and four tactors that were activated in pairs when body motion exceeded 1° anteriorly or posteriorly. A crossover design was used. On each day participants performed 24 repetitions of Sensory Organization Test condition 5 (SOT5), three repetitions each of SOT 1-6, three repetitions of the Motor Control Test, and five repetitions of the Adaptation Test. Performance metrics included A/P RMS, Time-in-zone and 95 % CI Ellipse. Performance improved with both cuing strategies but participants performed better when using repulsive cues. However, the rate of improvement was greater for attractive versus repulsive cuing.
  
  
  CONCLUSIONS
  The results suggest that when the cutaneous signal is interpreted as an alarm, cognition overrides sensory information. Furthermore, although repulsive cues resulted in better performance, attractive cues may be as good, if not better, than repulsive cues following extended training.
authors.affiliation: Department of Mechanical Engineering, University of Michigan, G.G. Brown Laboratory, 2350 Hayward St., 48109, Ann Arbor, MI, USA.
authors.forename: Catherine
authors.initials: C
authors.lastname: Kinnaird
authors.affiliation: Department of Mechanical Engineering, University of Michigan, G.G. Brown Laboratory, 2350 Hayward St., 48109, Ann Arbor, MI, USA.
authors.forename: Jaehong
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Otolaryngology, University of Michigan, 1500 E Medical Center Dr., 48109, Ann Arbor, MI, USA.
authors.forename: Wendy J
authors.initials: WJ
authors.lastname: Carender
authors.affiliation: Department of Internal Medicine, University of Michigan, 1500 East Medical Center Dr., 48109, Ann Arbor, MI, USA.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Kabeto
authors.affiliation: Department of Industrial & Operations Engineering, University of Michigan, 1205 Beal Ave, 48109, Ann Arbor, MI, USA.
authors.forename: Bernard
authors.initials: B
authors.lastname: Martin
authors.affiliation: Department of Mechanical Engineering, University of Michigan, G.G. Brown Laboratory, 2350 Hayward St., 48109, Ann Arbor, MI, USA. sienko@umich.edu.
authors.forename: Kathleen H
authors.initials: KH
authors.lastname: Sienko
mesh_terms: D000328:Adult; D000368:Aged; D003463:Cues; D056228:Feedback, Sensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D000066530:Neurological Rehabilitation / Q000295:instrumentation / Q000379:methods; D026741:Physical Therapy Modalities; D004856:Postural Balance / Q000502:physiology*; D014732:Vibration