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 ?
Thus, after about 10-20 seconds, due to the properties of the cupula, the optokinetic system acts as the back-up for longer periods of head rotation.
We found that people with Down had much diminished optokinetic and vestibular reflexes compared to typically developing individuals.
During optokinetic nystagmus testing, unilateral and bilateral impairments of the passive component were registered in 2(8.
All vertebrates with ocular motility (and many non-vertebrates) demonstrate an optokinetic response, (3) but there are two types of OKN: delayed OKN (OKNd) (also known as slow, slow build-up or indirect OKN), and early OKN (OKNe) (also known as fast, fast buildup or direct OKN).
Some laboratories also measure eye movements that do not produce vestibular nystagmus, such as saccades, smooth pursuit, pendular tracking, and optokinetic motion.
abnormal eye movements, (6) in combination with a vertical optokinetic nystagmus.
Alex Kiderman, Neuro Kinetics' chief technology officer, will report on data collected from varied sources, including a case study he co-authored suggesting that specific oculo-motor, optokinetic and vestibular tests conducted through the I-Portal systems can generate results that may identify mTBI not observable by other evaluation technologies, including MRIs.
Senescense of human visual-vestibular interactions: Smooth pursuit, optokinetic, and vestibular control of eye movements with aging.
Consequently, it is important to pay particular attention to assessment of ocular motility and pupil reactions when conducting a sight examination for patients with MSA, although more in-depth assessment of, for example, optokinetic nystagmus, is also required (see next article in this series for further details).
NKI's I-Portal NOTC system features the company's renowned Barany (rotational) chair, optokinetic ball and Pursuit Tracker(TM).
Specific tests conducted on the NKI employee before and after his accident and reported in the case study included optokinetic (OKN), spontaneous, pendular tracking, saccade, horizontal and vertical gaze, subjective visual vertical (SVV) and subjective visual horizontal (SVH), head thrust test (HTT), and sinusoidal harmonic acceleration test (SHA).
The ENG revealed normal optokinetics, a complete caloric areflexia on the right, an impossible left calorization on the left (which was caused by the obstruction of the external auditory canal by bone proliferation), and no response to rotatory testing.