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Vision research1992; 32(12); 2289-2293; doi: 10.1016/0042-6989(92)90092-w

Visual acuity in the horse.

Abstract: We assessed the ease with which horses could learn visual discriminations and measured their resolution acuity. We trained three horses to press their noses against one of two large wooden panels to receive a small food reward. Following training on a series of two-choice discrimination tasks, resolution acuity was measured. Although there was some variability between animals, the best acuity obtained was 23.3 c deg-1. Within the margin of error imposed by limited anatomical data, the obtained values are consistent with predictions based on retinal ganglion cell density estimates and posterior nodal distance/axial length ratios. They suggest that the resolution acuity of the horse is limited by ganglion cell density in the temporal portion of the narrow visual streak.
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Publication Date: 1992-12-01 PubMed ID: 1288005DOI: 10.1016/0042-6989(92)90092-wGoogle Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This study explores and measures the visual acuity of horses, primarily their ability to recognize details. The findings reveal that the resolution acuity of horses is likely limited by the density of ganglion cells in a specific part of the horse’s visual field.

Experiment Design

  • The researchers trained three horses to distinguish between two large wooden panels by pressing their noses against one of them in exchange for a small food reward. This created a setup in which horses had to rely on their vision to perform specific tasks, thereby allowing their visual abilities to be measured.
  • This experiment involved a series of two-choice discrimination tasks that were performed following the initial training. These tasks were used to measure the resolution acuity, or the ability to recognize minute details, of the horses.

Results and Observations

  • There was some variability observed in the results obtained from the individual animals, meaning that not all horses demonstrated the same level of visual acuity during this study.
  • The highest visual acuity recorded in this experiment was 23.3 cycles per degree, a measurement that describes the finest visual detail that an individual can perceive.
  • The results obtained match predictions made based on the retinal ganglion cell density and posterior nodal distance or axial length ratios.

Conclusions

  • The findings from this study suggest that the ganglion cell density in the temporal portion of the narrow visual streak determines the resolution acuity of the horse.
  • In simpler terms, the density of certain cells in part of the horse’s eye may limit the level of detail the horse can see.
  • The experiment’s results provided important insights into how vision works in horses and contributes to knowledge on mammalian vision more broadly.

Cite This Article

APA
Timney B, Keil K. (1992). Visual acuity in the horse. Vision Res, 32(12), 2289-2293. https://doi.org/10.1016/0042-6989(92)90092-w

Publication

Vision research
ISSN: 0042-6989
NlmUniqueID: 0417402
Country: England
Language: English
Volume: 32
Issue: 12
Pages: 2289-2293

Researcher Affiliations

Timney, B
  • Department of Psychology, University of Western Ontario, London, Canada.
Keil, K

    MeSH Terms

    • Animals
    • Discrimination, Psychological / physiology
    • Female
    • Horses / physiology
    • Pattern Recognition, Visual / physiology
    • Retinal Ganglion Cells / physiology
    • Sensory Thresholds / physiology
    • Visual Acuity / physiology

    Citations

    This article has been cited 16 times.
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