Human ocular counterrolling induced by varying linear accelerations.

B K Lichtenberg; L R Young; A P Arrott

doi:10.1007/bf00239580

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Human ocular counterrolling induced by varying linear accelerations.

B K Lichtenberg·L R Young·A P Arrott

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Abstract

Ocular counterrolling (OCR) has previously been studied using static head tilt or continuous rotation about the line of sight as a stimulus to the otolith organs. This study presents the first measurements of OCR in humans induced by linear accelerations. Dynamic measurements of the response to lateral linear acceleration indicate the eye movements to be on the order of 2 degrees for 0.2 g peak acceleration, 0.2 Hz sinusoidal acceleration. These values are consistent with static OCR studies. The dynamics of the response are similar to a low order linear system with a dominant time constant of 0.33 s. A previous model predicts a time constant of 0.32 s. Sinusoidal oscillation at 0.2, 0.4, and 1.0 Hz with a 0.2 g peak acceleration showed good agreement with the model in both gain and phase. The question of amplitude linearity remains unsettled. This otolithocular reflex, over short periods at least, appears to be stationary in the statistical sense.

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Acceleration Afferent Pathways Eye Movements Humans Models, Neurological Neck Muscles Nystagmus, Physiologic Orientation Otolithic Membrane Postural Balance Rotation Semicircular Canals Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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B K Lichtenberg, L R Young, A P Arrott. 1982. Human ocular counterrolling induced by varying linear accelerations.. https://doi.org/10.1007/bf00239580

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