Biomaterial Database

The effect of lateral head tilt on horizontal postrotatory nystagmus I and II and the Purkinje effect. 1985

V Schrader, and E Koenig, and J Dichgans

The influence of an active lateral head tilt on postrotatory nystagmus I and II (PI, PII) was explored in normal humans. During postrotatory nystagmus the head was tilted laterally either towards the direction of the previous rotation (ipsilateral tilt) or towards the opposite direction (contralateral tilt) or the head was kept erect. Both ipsi- and contralateral head tilts led to a substantially weaker and shorter PI and PII as compared with the trial without head tilt. The time constants of the decline of PI were shortened to the ones observed in the peripheral nerve of animals. The reduction of PI and PII suggests a position-dependent tonic inhibition of the vestibular storage mechanism in the vestibular nuclei probably by the otoliths. The stronger reduction of time constant and cumulative amplitude of PI after contralateral as compared with ipsilateral head tilt may be explained by different combinations of asymmetric responses in canal and otolith afferents.

UI	MeSH Term	Description	Entries
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
D005133	Eye Movements	Voluntary or reflex-controlled movements of the eye.	Eye Movement,Movement, Eye,Movements, Eye
D006257	Head	The upper part of the human body, or the front or upper part of the body of an animal, typically separated from the rest of the body by a neck, and containing the brain, mouth, and sense organs.	Heads
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D012444	Saccule and Utricle	Two membranous sacs within the vestibular labyrinth of the INNER EAR. The saccule communicates with COCHLEAR DUCT through the ductus reuniens, and communicates with utricle through the utriculosaccular duct from which the ENDOLYMPHATIC DUCT arises. The utricle and saccule have sensory areas (acoustic maculae) which are innervated by the VESTIBULAR NERVE.	Otolithic Organs,Utricle,Saccule,Organ, Otolithic,Otolithic Organ,Saccules,Utricle and Saccule,Utricles
D012677	Sensation	The process in which specialized SENSORY RECEPTOR CELLS transduce peripheral stimuli (physical or chemical) into NERVE IMPULSES which are then transmitted to the various sensory centers in the CENTRAL NERVOUS SYSTEM.	Sensory Function,Organoleptic,Function, Sensory,Functions, Sensory,Sensations,Sensory Functions
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor