title: Evaluation of a non-invasive vocal cord vibration switch as an alternative access pathway for an individual with hypotonic cerebral palsy - a case study.
abstract: OBJECTIVE
  A novel non-invasive vocal cord vibration switch for computer access was designed for an individual with hypotonic cerebral palsy. An evaluative case study was performed to compare the new device to an existing commercially available voice-activated switch in terms of sensitivity, specificity, speed, and user fatigue.
  
  
  METHODS
  The participant wrote pangram sentences with the two switches over 4 days with two sessions each day (morning and afternoon). The order of the switches was alternated and a new sentence was used each day. The user's perceived level of exertion was noted before and after each task and activation errors were logged for performance analysis. After using the device for 2 months, a qualitative survey was administered with the participant and his educational assistant.
  
  
  RESULTS
  The vocal cord vibration switch outperformed the voice-activated switch in terms of sensitivity (p < 10(-4), t-test), speed (p < 10(-3)), and user-perceived exertion (p < 10(-4)). Qualitatively, both the participant and his educational assistant were more satisfied with the proposed switch relative to his existing solution.
  
  
  CONCLUSIONS
  The results of this study show that the vocal cord vibration switch provides a promising new alternative for individuals with severe and multiple disabilities who are able to hum or produce vocalizations.
authors: Bloorview Research Institute, Bloorview Kids Rehab, Toronto, Ontario, Canada.
authors: Julie
authors: J
authors: Chan
authors: Tiago H
authors: TH
authors: Falk
authors: Gail
authors: G
authors: Teachman
authors: Jennifer
authors: J
authors: Morin-McKee
authors: Tom
authors: T
authors: Chau
mesh_terms: D002547:Cerebral Palsy / Q000175:diagnosis* / Q000534:rehabilitation*; D006233:Persons with Disabilities / Q000534:rehabilitation; D004867:Equipment Design; D004869:Equipment Safety; D006801:Humans; D008297:Male; D026741:Physical Therapy Modalities / Q000295:instrumentation; D011788:Quality of Life; D012656:Self-Help Devices; D012720:Severity of Illness Index; D013647:Task Performance and Analysis; D014732:Vibration; D014827:Vocal Cords / Q000502:physiology*; D055815:Young Adult