Optokinetic response

Horizontal optokinetic nystagmus.
Stare nystagmus for a random dot pattern moving from left to right.

The optokinetic response is a combination of a slow-phase and fast-phase eye movements. It is seen when an individual tracks (pursuit movement) a moving object with their eyes, which then moves out of the field of vision at which point their eye moves back to the position it was in (saccade movement) when it first saw the object. The reflex develops at about 6 months of age.[1]

Optokinetic nystagmus/response (OKN/R) is nystagmus that occurs in response to a visual stimulus on the retina.[2] It is present in normally developed patients. The optokinetic response allows the eye to follow objects in motion when the head remains stationary (e.g., observing individual telephone poles on the side of the road as one travels by them in a car, or observing stationary objects while walking past them).

Diagnosis

Eliciting optokinetic nystagmus

With normal vision, an OKN response develops in infants and remains through adulthood. The OKN response consists of initial slow phases in the direction of the stimulus (smooth pursuits), followed by fast, corrective phases (return saccade).[2][3] Presence of an OKN response in the temporal to nasal direction indicates an intact visual pathway.[4] Another effective method is to hold a mirror in front of the patient and slowly rotate the mirror to either side of the patient. The patient with an intact visual pathway will maintain eye contact with themselves. This compelling optokinetic stimulus forces reflex slow eye movements.

Stereopsis development

This is particularly helpful in infantile strabismus to determine if motion stereopsis development is present or not.[5][6] Nasal to temporal motion tracking can be trained in infantile strabismus allowing for eye alignment (Baxtrom and Clopton, 2019) and may be associated with the Accessory Optic System for eye control.[5][6]

See also

References

  1. ↑ Atkinson J (1984). "Human visual development over the first 6 months of life. A review and a hypothesis". Hum Neurobiol. 3 (2): 61–74. PMID 6378843.
  2. 1 2 Tabata, Hiromitsu; Shimizu, Naoki; Wada, Yoshiro; Miura, Kenichiro; Kawano, Kenji (2010-01-02). "Initiation of the optokinetic response (OKR) in mice". Journal of Vision. 10 (1): 13.1–17. doi:10.1167/10.1.13. ISSN 1534-7362. PMID 20143906.
  3. ↑ Cahill, Hugh; Nathans, Jeremy (2008-04-30). "The Optokinetic Reflex as a Tool for Quantitative Analyses of Nervous System Function in Mice: Application to Genetic and Drug-Induced Variation". PLOS ONE. 3 (4): e2055. Bibcode:2008PLoSO...3.2055C. doi:10.1371/journal.pone.0002055. ISSN 1932-6203. PMC 2323102. PMID 18446207.
  4. ↑ Katoh, Akira; Kitazawa, Hiromasa; Itohara, Shigeyoshi; Nagao, Soichi (1998-06-23). "Dynamic characteristics and adaptability of mouse vestibulo-ocular and optokinetic response eye movements and the role of the flocculo-olivary system revealed by chemical lesions". Proceedings of the National Academy of Sciences. 95 (13): 7705–7710. Bibcode:1998PNAS...95.7705K. doi:10.1073/pnas.95.13.7705. ISSN 0027-8424. PMC 22730. PMID 9636214.
  5. 1 2 Hwang, J. M.; Matsumoto, E. R.; Borchert, M. S. (August 1999). "The relationship between stereopsis and monocular optokinetic optokinetic nystagmus after infantile cataracts". Journal of AAPOS. 3 (4): 221–226. doi:10.1016/s1091-8531(99)70006-6. ISSN 1091-8531. PMID 10477224.
  6. 1 2 Wattam-Bell, John (2003-08-01). "Motion processing asymmetries and stereopsis in infants". Vision Research. 43 (18): 1961–1968. doi:10.1016/S0042-6989(03)00282-7. ISSN 0042-6989. PMID 12831758. S2CID 14158594.
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