I conducted an experiment in order to determine whether horses could look for information that had been present previously and would inform them on how to receive the reward for this task. One of two horses learned to use a cue to identify where a food reward was located. This horse then failed to learn to move or look behind a sheet that would have revealed for her a previously learned discriminative cue, leading her to a food reward. These results were discussed in relation to other breeds of horses, the possible measurement of neural activity and the need for more effective methods to test metacognition in animals.
Zupet, Kristen E.
"Metacognition: Metamemory in Horses,"
The Huron University College Journal of Learning and Motivation: Vol. 48
, Article 15.
Available at: http://ir.lib.uwo.ca/hucjlm/vol48/iss1/15