Biomaterial Database

The horizontal vestibulo-ocular reflex during linear acceleration in the frontal plane of the cat. 1991

D E Angelaki, and J H Anderson

Department of Otolaryngology, University of Minnesota, Minneapolis 55455.

Horizontal and vertical eye movements were recorded in alert, restrained cats that were subjected to whole-body rotations with the horizontal semicircular canals in the plane of rotation and the body centered on the axis or 45 cm eccentric from the axis of rotation. Changes in the horizontal vestibulo-ocular reflex (HVOR) due to the resultant of the linear forces (i.e., gravity and linear acceleration) acting on the otolith organs were examined during off-axis rotation when there was a centripetal acceleration along the animal's interaural axis. The HVOR time constant was slightly shortened when the resultant otolith force was not parallel to the animal's vertical axis. This effect was independent of the direction of the otolith force relative to the direction of the slow phase eye velocity. No effect on the HVOR amplitude was observed. In addition to changes in the HVOR dynamics, a significant vertical component of eye velocity was observed during stimulation of the horizontal canals when the resultant otolith force was not parallel with the animal's vertical axis. The effect was greater for larger angles between the resultant otolith force and gravity. An upward or downward component was elicited, depending on the direction of the horizontal component of eye velocity and the direction of the resultant otolith force. The vertical component was always in the direction that would tend to align the eye velocity vector with the resultant otolith force and keep the eye movement in a plane that had been rotated by the angle between the resultant otolith force and gravity.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009760	Nystagmus, Physiologic	Involuntary rhythmical movements of the eyes in the normal person. These can be naturally occurring as in end-position (end-point, end-stage, or deviational) nystagmus or induced by the optokinetic drum (NYSTAGMUS, OPTOKINETIC), caloric test, or a rotating chair.	Nystagmus, Barany,Nystagmus, Caloric,Nystagmus, End-Position,Nystagmus, Positional,Nystagmus, Post-Rotatory,Nystagmus, Thermal,Nystagmus, Barany's,Nystagmus, Physiological,Physiologic Nystagmus,Barany Nystagmus,Barany's Nystagmus,Caloric Nystagmus,End-Position Nystagmus,Nystagmus, Baranys,Nystagmus, End Position,Nystagmus, Post Rotatory,Physiological Nystagmus,Positional Nystagmus,Post-Rotatory Nystagmus,Thermal Nystagmus
D010037	Otolithic Membrane	A gelatinous membrane overlying the acoustic maculae of SACCULE AND UTRICLE. It contains minute crystalline particles (otoliths) of CALCIUM CARBONATE and protein on its outer surface. In response to head movement, the otoliths shift causing distortion of the vestibular hair cells which transduce nerve signals to the BRAIN for interpretation of equilibrium.	Otoconia,Otoliths,Statoconia,Membrane, Otolithic,Membranes, Otolithic,Otoconias,Otolith,Otolithic Membranes,Statoconias
D011187	Posture	The position or physical attitude of the body.	Postures
D012027	Reflex, Vestibulo-Ocular	A reflex wherein impulses are conveyed from the cupulas of the SEMICIRCULAR CANALS and from the OTOLITHIC MEMBRANE of the SACCULE AND UTRICLE via the VESTIBULAR NUCLEI of the BRAIN STEM and the median longitudinal fasciculus to the OCULOMOTOR NERVE nuclei. It functions to maintain a stable retinal image during head rotation by generating appropriate compensatory EYE MOVEMENTS.	Vestibulo-Ocular Reflex,Reflex, Vestibuloocular,Reflexes, Vestibo-Ocular,Reflexes, Vestibuloocular,Reflex, Vestibulo Ocular,Reflexes, Vestibo Ocular,Vestibo-Ocular Reflexes,Vestibulo Ocular Reflex,Vestibuloocular Reflex,Vestibuloocular Reflexes
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D005133	Eye Movements	Voluntary or reflex-controlled movements of the eye.	Eye Movement,Movement, Eye,Movements, Eye
D000054	Acceleration	An increase in the rate of speed.	Accelerations
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012399	Rotation	Motion of an object in which either one or more points on a line are fixed. It is also the motion of a particle about a fixed point. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Clinorotation,Clinorotations,Rotations