title: The influence of an auditory-memory attention-demanding task on postural control in blind persons.
abstract: BACKGROUND
  In order to evaluate the effect of an auditory-memory attention-demanding task on balance control, nine blind adults were compared to nine age-gender-matched sighted controls. This issue is particularly relevant for the blind population in which functional assessment of postural control has to be revealed through "real life" motor and cognitive function. The study aimed to explore whether an auditory-memory attention-demanding cognitive task would influence postural control in blind persons and compare this with blindfolded sighted persons.
  
  
  METHODS
  Subjects were instructed to minimize body sway during narrow base upright standing on a single force platform under two conditions: 1) standing still (single task); 2) as in 1) while performing an auditory-memory attention-demanding cognitive task (dual task). Subjects in both groups were required to stand blindfolded with their eyes closed. Center of Pressure displacement data were collected and analyzed using summary statistics and stabilogram-diffusion analysis.
  
  
  RESULTS
  Blind and sighted subjects had similar postural sway in eyes closed condition. However, for dual compared to single task, sighted subjects show significant decrease in postural sway while blind subjects did not.
  
  
  CONCLUSIONS
  The auditory-memory attention-demanding cognitive task had no interference effect on balance control on blind subjects. It seems that sighted individuals used auditory cues to compensate for momentary loss of vision, whereas blind subjects did not. This may suggest that blind and sighted people use different sensorimotor strategies to achieve stability.
authors.affiliation: Rehabilitation and Movement Analysis Laboratory in the Leon and Matilda Recanati School for Community Health Professions, Physical Therapy Department, Faculty of Health Sciences at Ben-Gurion University of the Negev, Beer-Sheva, Israel. itzikm@bgumail.bgu.ac.il
authors.forename: Itshak
authors.initials: I
authors.lastname: Melzer
authors.forename: Elad
authors.initials: E
authors.lastname: Damry
authors.forename: Anat
authors.initials: A
authors.lastname: Landau
authors.forename: Ronit
authors.initials: R
authors.lastname: Yagev
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D001766:Blindness / Q000503:physiopathology*; D016022:Case-Control Studies; D003071:Cognition; D005260:Female; D006309:Hearing; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D004856:Postural Balance / Q000502:physiology*; D011312:Pressure; D013997:Time Factors; D019987:Persons with Visual Disabilities