Perception of Passive Whole-Body Rotations in the Absence of Neck and Body Proprioception. Blouin, Jean, Jean-Louis Vercher, Gabriel M. Gauthier, Jacques Paillard, Chantal Bard, and Yves Lamarre. Laboratoire de Contr[circumflex]oles Sensorimoteurs, URA CNRS 1166, Universit[acute]e de Provence, Avenue Escadrille Normandie-Niemen 13397 Marseille Cedex 20 (France). Phone: 91.28.82.36; Fax: 91.02.05.50 Email: ? labocsm@vmesa11.u-3mrs.fr, Laboratoire de Neurosciences Fonctionnelles, CNRS, Marseille, Laboratoire de Performance Motrice Humaine, Universit[acute]e Laval, Sainte-Foy, Qu[acute]ebec, Centre de Recherche en Sciences Neurologiques, Universit[acute]e de ? Montr[acute]eal, Montr[acute]eal, Qu[acute]ebec.
APStracts 2:0255N, 1995.
SUMMARY AND CONCLUSIONS
1. This study investigated whether accurate perception of body rotation after passive horizontal whole-body rotations in the dark requires the integration of both vestibular and neck-body proprioceptive signals. 2. In the first experiment, the gain of the vestibulo-ocular reflex (VOR) of normal subjects ('controls') and of a patient without proprioception of the neck and body muscles was assessed using pulse and sinusoidal stimulation. In the second experiment, the subjects reported verbally the magnitude of the body rotations. Finally, in the third experiment, they shifted gaze to the position fixated before the rotation ['vestibular memory-contingent saccades' paradigm, Bloomberg et al. (1988)]. 3. The VOR gain of the patient was similar to that of controls, although the body rotations of the patient were largely overestimated, regardless of whether the patient reported the perceived magnitude verbally or through a gaze shift towards the position gazed at before the rotation. 4. These results suggest that neck muscle proprioception contributes to the vestibular signal calibration at the perceptual level necessary for determining body orientation accurately after rotations in the dark. 

Received 29 November 1995; accepted in final form 10 August 1995.
APS Manuscript Number J744-4.
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 24 August 1995.