Chaser’s owner, retired Wofford College psychologist John Pilley, has authored a study about his dog’s extraordinary ability to not only understand words, but to understand full sentences.
After completing extensive positive reinforcement training in the canine equivalent of basic phonics and sentence structure, Chaser could understand different types of words — nouns, verbs, direct objects, and prepositions. Pilley then tested Chaser’s new knowledge by seeing whether or not she could respond correctly to differently-phrased commands. For example, Pilley would tell Chaser “to ball take Frisbee” followed by “to Frisbee take ball,” then monitor Chaser’s response.
“Chaser intuitively discovered how to comprehend sentences based on lots of background learning about different types of words,” Pilley tells Science News.
“Successive findings were attributed to Chaser’s intensive training in her first three years of life,” Dr. Pilley writes in his study.
While Pilley says it is clear that Chaser has learned a basic understanding of grammar and semantics, it is not clear exactly how she’s done so. Pilley believes Chaser must have first made a mental link between each of the two nouns she heard in a sentence command — the nouns “ball” and “Frisbee,” for example — and the objects themselves. Then she must have stored that information — the noun/object pairings — in her mind while decoding which objects to bring to which objects, Dr. Pilley explains.
Chaser also holds a record for the largest vocabulary of any canine. In 2011, Chaser proved she could recognize 1,022 words by fetching specific toys from randomized groups. The brainy Border Collie performed over 830 different tests, each time scoring at least 90 percent correct. Chaser’s amazing abilities as a canine wordsmith give her an intelligence level equivalent to that of a 3-year-old human child, according to a 2011 article published in the Huffington Post. The previous record-holder, a Border Collie named Rico, had a vocabulary of only about 200 words.
To learn more about Chaser, check out Dr. Pilley’s and Chaser’s remarkable demonstrations on YouTube. The results of Pilley’s study have also been published in the May 13 issue of the scientific journal Learning and Motivation.