The Effect of Gravitoinertial Force Upon Ocular Counterrolling

Résumé du livre

The effect in terms of magnitude of ocular counterrolling of g- loading at various angles of tilt up to 63 degrees was measured on normal subjects and compared with the effect upon persons with severe or complete loss of otolith function. The group of six normal subjects manifested a compensatory eye roll which increased as a direct and essentially linear function of the component of the gravitoinertial force acting laterally upon the subject. This increase in response was not observed in the five deaf subjects with severe or complete bilateral loss of their vestibular organs. These findings confirmed similar results found by other authors using other measuring techniques which show that the reflex eye movement is dependent upon and limited to the magnitude of the gravitoinertial stimulus (within the range used) when the otolitho-ocular system is functioning normally. However, when this function is impaired or lost, the magnitude of the compensatory eye roll is limited to that manifested at 1 g and possibly to non-otolithic contributions. These findings offer means for differentiation between otolithic defective individuals and 'normal' persons who exhibit little counterrolling.