Cognitive testing in horses using a computer based apparatus

For the study of higher order cognition, the matching to sample procedure presents an established method to test relational concept learning in several species. In the present study we designed a method of testing ponies via a computer based model. We used the advantages of an automatic stimulus control system which enabled a better standardization of stimulus presentation and sequencing, and shorter test periods for the animals. Three stages of learning were used to prepare seven Shetland ponies for matching to sample and final transfer tests. Learning criterion was set to 80% on two consecutive sessions including 20 trials per session. In the pretest, all seven ponies solved the operant conditioning task to push one of two buttons to receive a reward. Learning step 1 included the association between a stimulus presented on one side of a LCD screen and pushing the related button, which was accomplished by five ponies between sessions 8 and 55. Four individuals learnt the next step and were able to relate geometric symbols to each other in a matching to sample arrangement. In a subsequent test the ponies successfully transferred the learned task to completely new stimuli within 2-8 sessions with a performance level above 80%. We discuss several learning strategies which could have been involved in the observed learning process. The correct initial responses in the transfer tests suggest that ponies are able to acquire at least relational rules and transfer these to new stimuli.