Vestibular perception and navigation in the congenitally blind
Author(s)
Seemungal, Barry M
Glasauer, Stefan
Gresty, Michael A
Bronstein, Adolfo M
Type
Journal Article
Abstract
Vestibular input is required for accurate locomotion in the dark, yet blind subjects’ vestibular function is unexplored. Such investigation may also identify visually dependent aspects of vestibular function. We assessed vestibular function perceptually in six congenitally blind (and 12 sighted) subjects. Cupula deflection by a transient angular, horizontal acceleration generates a related vestibular nerve signal that declines exponentially with time constant ≈4–7 s, which is prolonged to 15 s in the evoked vestibular-ocular reflex by the brain stem “velocity storage.” We measured perceptual velocity storage in blind subjects following velocity steps (overall perceptual vestibular time constant, experiment 1) and found it to be significantly shorter (5.34 s; range: 2.39–8.58 s) than in control, sighted subjects (15.8 s; P < 0.001). Vestibular navigation was assessed by subjects steering a motorized Bárány-chair in response to imposed angular displacements in a path-reversal task, “go-back-to-start” (GBS: experiment 2); and a path-completion task, “complete-the-circle” (CTC: experiment 3). GBS performances (comparing response vs. stimulus displacement regression slopes and r2) were equal between groups (P > 0.05), but the blind showed worse CTC performance (P < 0.05). Two blind individuals showed ultrashort perceptual time constants, high lifetime physical activity scores and superior CTC performances; we speculate that these factors may be inter-related. In summary, the vestibular velocity storage as measured perceptually is visually dependent. Early blindness does not affect path reversal performance but is associated with worse path completion, a task requiring an absolute spatial strategy. Although congenitally blind subjects are overall less able to utilize spatial mechanisms during vestibular navigation, prior extensive physical spatial activity may enhance vestibular navigation.
Date Issued
2007-06-01
Date Acceptance
2007-03-15
Citation
Journal of Neurophysiology, 2007, 97 (6), pp.4341-4356
ISSN
0022-3077
Publisher
American Physiological Society
Start Page
4341
End Page
4356
Journal / Book Title
Journal of Neurophysiology
Volume
97
Issue
6
Copyright Statement
Copyright © 2007 by the American Physiological Society
Identifier
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000247938200045&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=a2bf6146997ec60c407a63945d4e92bb
Subjects
CIRCULAR LOCOMOTION
Life Sciences & Biomedicine
Neurosciences
Neurosciences & Neurology
OCULAR REFLEX
PATH-INTEGRATION
Physiology
RUNNING MONKEY
Science & Technology
SELF-MOTION
SEMICIRCULAR CANALS
SPATIAL MEMORY
VELOCITY STORAGE
VESTIBULOOCULAR REFLEX
VISUALLY-IMPAIRED CHILDREN
Publication Status
Published
Date Publish Online
2007-06-01