Pavlov’s Horses: Conditioned Response Shown in Equines

More than a century ago, Ivan Pavlov, a Russian scientist, discovered that dogs salivated in anticipation of being given food. Pavlov began ringing a bell as the dogs were about to be fed, and after a short time he was able to cause the dogs to salivate in response to the sound of the bell even when food was not present. Pavlov termed this phenomenon a conditioned response.

Recently, researchers in France used 19 Anglo-Arab horses from the French National Stud to investigate conditioned responses in horses, and expanded the research to show that individual temperament can play an important part in each animal’s response. The group of horses was made up of both males and females, and all horses were used to being handled.

In the first part of the trial, horses listened to feed pellets being shaken in a plastic jug, after which each horse was given a small handful of pellets in a feed bucket. The horses were then taught to touch a cone when signaled by the researcher in order to obtain a food reward. Finally, the cone touch was repeated but the food rewards were systematically withdrawn. Thus, the horses were conditioned to touch the cone after they heard the signal, even though food was not given. This progression through a series of responses was termed a Pavlovian-to-instrumental transfer (PIT) test.

Behavioral tests were then performed on all the horses to assess characteristics of temperament and their relation to the results of each horse’s PIT test. Fearfulness, gregariousness, level of activity, sensory sensitivity, and reactivity to humans were evaluated. The results showed that the horses with the higher levels of gregariousness, fearfulness, and sensory sensitivity had the strongest Pavlovian response.

The researchers suggested that the Pavlovian response might play an important part in the use of various training methods. They felt that horses with fearful, gregarious, and sensitive temperaments also had specific cognitive abilities that functioned independent of the stress associated with learning processes, and thought these horses learned well because they had enhanced accuracy in processing of environmental cues.