optokinetic


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nystagmus

 [nis-tag´mus]
involuntary, rapid, rhythmic movement (horizontal, vertical, rotatory, or mixed, i.e., of two types) of the eyeball. adj., adj nystag´mic.
amaurotic nystagmus nystagmus in the blind or in those with defects of central vision.
amblyopic nystagmus nystagmus due to any lesion interfering with central vision.
aural nystagmus labyrinthine nystagmus.
caloric nystagmus rotatory nystagmus in response to caloric stimuli in the ear, seen during the caloric test.
Cheyne's nystagmus a peculiar rhythmical eye movement resembling Cheyne-Stokes respiration in rhythm.
congenital nystagmus (congenital hereditary nystagmus) nystagmus usually present at birth, usually horizontal and pendular, but occasionally jerky and pendular; the nystagmus may be caused by or associated with optic atrophy, coloboma, albinism, bilateral macular lesions, congenital cataract, severe astigmatism, and glaucoma.
dissociated nystagmus that in which the movements in the two eyes are dissimilar.
end-position nystagmus that occurring only at extremes of gaze.
fixation nystagmus that occurring only on gazing fixedly at an object.
gaze nystagmus nystagmus made apparent by looking to the right or to the left.
labyrinthine nystagmus vestibular nystagmus due to labyrinthine disturbance.
latent nystagmus that occurring only when one eye is covered.
lateral nystagmus involuntary horizontal movement of the eyes.
optokinetic nystagmus nystagmus induced by looking at objects moving across the visual field.
pendular nystagmus nystagmus in which the oscillations of the eyes have an equal rate, amplitude, direction, and type of movement.
positional nystagmus that which occurs, or is altered in form or intensity, on assumption of certain positions of the head.
retraction nystagmus (nystagmus retracto´rius) a spasmodic backward movement of the eyeball occurring on attempts to move the eye; a sign of midbrain disease.
rotatory nystagmus involuntary rotation of the eyes about the visual axis.
secondary nystagmus nystagmus occurring after the abrupt cessation of rotation of the head, caused by the labyrinthine fluid continuing to move.
spontaneous nystagmus that occurring without specific stimulation of the vestibular system.
vertical nystagmus involuntary up-and-down movement of the eyes.
vestibular nystagmus nystagmus due to disturbance of the labyrinth or of the vestibular nuclei; the movements are usually jerky.

op·to·ki·net·ic nys·tag·mus

nystagmus induced by looking at moving visual stimuli.

optokinetic

/op·to·ki·net·ic/ (op″to-kĭ-net´ik) pertaining to movement of the eyes, as in nystagmus.

optokinetic

[op′tōkinet′ik]
Etymology: Gk, optikos, sight, kinesis, motion
pertaining to movement of the eyeballs in response to the movement of objects across the visual field, such as in optokinetic nystagmus. Also opticokinetic.

optokinetic 

Term referring to movements of the eyes in response to the movement of objects across the visual field. Example: optokinetic nystagmus. See vestibulo-ocular reflex.

optokinetic

pertaining to movement of the eyes, as in nystagmus.
References in periodicals archive ?
The scientists lesioned these projections and again observed a decrease in the optokinetic reflex.
Perception of self-motion from peripheral optokinetic stimulation suppresses visual evoked responses to central stimuli.
The second correlates the incidence of dizziness with ocular motor, optokinetic and postural function.
Some of the earliest descriptions of eye movement were by Erasmus Darwin,[3] who reported how changes in body position affected eye movements, and by Purkinje,[12] who described optokinetic eye movements in people watching a cavalry parade.
STOCKHOLM -- Tobii Technology's partner i2Eye Diagnostics has developed a portable, patient-friendly solution -- Saccadic Vector Optokinetic Perimetry (SVOP) -- that assists clinicians in the diagnosis of ophthalmic and neurological conditions and can also provide valuable research applications.
Thus, the vestibular patients are exposed to optokinetic stimuli delivered via projection screens such as ballroom planetariums, or using plane rotating optokinetic discs.
20) In mice, besides VOR adaptation, adaptation of optokinetic response (OKR) has also been studied as a model motor learning.
That's likely because Down syndrome affects the optokinetic and vestibular systems of the brain.
ENG testing included calibration, identification of spontaneous nystagmus and gaze nystagmus, positional tests, Dix-Hallpike maneuvers (unless contraindicated because of neck pathology), sinusoidal tracking, optokinetic testing and, in selected patients, alternate binaural bithermal caloric testing (right warm [RW]; right cool [RC]; left warm [LW]; left cool [LC]).
Neuronal activity in the vestibular nuclei of the alert monkey during vestibular and optokinetic stimulation.
The optokinetic nystagmus test uses a black-and-white striped cylinder called the optokinetic nystagmus drum (OKN drum).
Many physiologists and anatomists also include prepositus hypoglossi as a subnucleus of the VNC, since it receives input from other vestibular subnuclei and is intimately involved in the control of the vestibulo-ocular and optokinetic reflexes (see Leigh & Zee, 1991 for a review).