• Why Horses Wear Blinders

    Written By: W. Banks Anderson Jr., MD

    If you have never had a spot right on the rail in the infield of a horse racing track, put it on your bucket list. “Thrill” implies a bit of fear. Leaning on the rail as that first one-ton beast hurtles towards you can really squeeze the adrenals, especially so in Barbados, where the rail is a warped 2x4. For me the Derby and the Preakness recall a bit of that thrill and I enjoy the spectacle. This May the Preakness was run in a rainstorm and the track was sloppy, with mud flying. All the jockeys wore their goggles, but what about the horses?

    Horses are commonly fitted with eye wear. Blinders, blinkers and winkers are some of their names. Seldom are there any lenses in these devices, nor do they usually blind. But trainers and handlers have a widespread belief that you can modify a horse’s behavior by limiting its visual field in many and various ways, with many and various appliances.

    Predators like we humans, hyenas and owls have frontal eyes with overlapping visual fields. Prey, like horses, herring and orioles, have lateral eyes that monitor much more of their environment. Thus, horses are stupid enough to submit to being ridden and driven, but also may rear or bolt at just a glimpse of a windswept plastic bag.

    During the last centuries, horse trainers and handlers have adopted the dictum, “Out of sight, out of mind.” Consequently, draft horses are fitted with blinders or blinkers made of leather squares on their bridle tack, which totally obstruct the rear visual fields of both eyes.

    In addition, hoods may be fitted over a horse’s ears that contain field-restricting eye cups. Racing trainers often selectively configure the cups in hopes of modifying their animal’s behavior. For example, they cut holes in the back of full eye cups in the hope that the horse might go faster if it could sense horses gaining on it from behind. Or, a trainer might block most of the right eye’s visual field hoping to eliminate a tendency to bear right. Secretariat famously was fitted with blinkers installed in his trademark blue and white hood.

    In the early furlongs of this May’s Preakness Mr. Z was slopping along in second place, catching American Pharaoh’s (that’s Jockey Club spelling) mud. He was blinkered in a white hood with eye cups and was easy to spot. Mr. Lucas, his trainer, said later: “He caught a lot of mud in those full cup blinkers” -- implying that Mr. Z might not have faded to fifth on a dry course. All the jockeys in the race wore goggles, but thought it is possible to put similar polycarbonate windows in horses’ eye cups, they seem rarely to be used.

    According to the Times of Israel, humans have also been fitted with blinkers. In 2012, the Committee for Purity was reported to have provided spectacle stick-ons to ultraorthodox Jewish men to protect them from the many impure and lascivious images in their environment. Should they neither need nor have spectacles, this appliance was also thoughtfully provided by the Committee.

    The effect of these blinkers seems to have been more one of blur production than of field restriction. They may merely have reduced acuity to the level of 20/60 or so -- similar to that of horses, spectacled sailors in ocean spray or anyone tearing up from a mote of mud in the eye.