Learning to associate words with certain items is certainly an impressive talent, especially when it comes to dogs! How many words can a dog learn? Rico, the border collie, has shown the ability to learn over 200. Juliane Kaminski from the Max Planck Institute for Evolutionary Anthropology along with colleagues, has studied this remarkable border collie. The results of the study clearly demonstrated that Rico was capable of getting 37 out of 40 items correctly! In order to properly study this dog, a scientific approach was needed to rule out other phenomena which could have explained this dog's ability to discriminate words from one another.
Ruling Out the "Clever Hans" Effect
One phenomenon to rule out included the dog's reliance on subtle cues sent from the owner. Dogs are very attentive to our body language, so it's easy for them to select certain items simply because we are moving our heads in that direction or looking at the item.
We may do this unintentionally, but dogs being masters in reading body language, feed into these cues.
Many years ago, a horse going by the name of Clever Hans, was found to be capable of resolving arithmetic calculations. The horse was asked to solve a math problem and he would tap his hoof to give the answer.
After an investigation conducted in 1907, psychologist Oskar Pfungst proved that the horse wasn't actually counting, but was actually responding to involuntary, subtle cues sent out by his trainer!
Turns out, the horse was quite sensitive to the building tension of his trainer when he was asked to solve a math problem and the release of tension when he got to the correct number. This release of tension therefore informed the horse that it was time to stop tapping his hoof. Because of this phenomenon, now, people studying animal cognition refer to it as "The Clever Hans effect."
Out of Sight
So in the study of Rico, the border collie who knew 200 words, it was important to rule out the Clever Hans effect.
This was done by asking the dog to fetch the toy by its name with the owner in another room. This prevented the dog from reading the owner's cues (such as looking at a particular item) and would have proven that this dog was actually capable of fetching the correct toy because he really associated the word with that particular toy.
The results revealed that Rico was actually, capable of understanding words and his vocabulary proved to be quite broad when compared to the vocabulary of parrots, apes, sea lions and dolphins!
Proof of Fast Mapping
So if Rico wasn't relying on any subtle cues sent by his owner, how was he capable of learning so many words? Turns out, he was utilizing the same mechanism humans use, a mechanism known as "fast mapping."
Fast mapping is a mental process where concepts are learned based on a single exposure. Children during the language acquisition phase, learn many words each day by relying on this mechanism.
To prove that Rico was capable of learning based on a single exposure, a novel item was introduced among familiar ones in a single exposure. Rico was then asked to retrieve the new object by using the novel word. So Rico went off to select the toy, and possibly, through a process of elimination, determined that the novel word must have been used to refer to the novel toy.
Referent Selection and Retention
In order to learn through fast mapping, two conditions needs met: referent selection and referent retention. In referent selection, the dog must associate a word with a particular item; whereas, in referent retention, the dog must be able to store the word in his memory for later use.
After learning a new word after only one exposure, Rico was tested a month later to see if he retained the understanding of that word.
Surprisingly, Rico was able to correctly retrieve the item as much as 50 percent of the time, a success rate that matches that of a 3-year-old child!
Rico's behavior was quite remarkable indeed. Further proof of understanding words was proved by other dogs with an even more vast knowledge of words. Betsy, another border collie, showed she was capable of understanding over 340 words, but as of 2010, Chaser, another border collie beats all with a vocabulary of an astounding 1022 words! Yes, you read right, that's 1022 words!
This can make us wonder if border collies have superior cognitive abilities when it comes to understanding the meaning of words. If we think of it, border collies were selectively bred to herd, and throughout the years, have shown a remarkable ability to understand voice commands and whistles, so perhaps, there may be a genetic predisposition at play. Yet, with the right training, any dog regardless of breed can learn the meaning of words if you know how to teach them.
Words From Rover's Perspective
As much as the behaviors of Rico, Betsy and Chaser are impressive, they are still a far cry from the way humans perceive words.
Humans have the cognitive ability to perceive abstract concepts such as the words love, friendship and sincerity. Dogs on the other other hand, are more down to earth, and mainly learn words that are under the form of objects or actions.
Even though your dog may seem to understand a sentence such as " do you want to go out?" and gets all excited when he hears that as it's always followed by you walking by the door and opening it, he may not understand more complex concepts or phrases such "you can't have the cookie now" as the word "can't" isn't understood, but since the word cookie may be, likely your dog may get all excited and then feel frustrated when he doesn't get the cookie.
Your dog may not know an impressive number of words compared to Rico, Betsy or Chaser, yet consider that many dogs respond to cues present in their environment which often speak for themselves. For instance, the noise of the leash becomes synonymous with walk, the noise of the food bag becomes synonymous with dinner, when you wear your shoes, your dog knows that means you're heading out, when you grab the car keys it likely (and hopefully!) means car ride, and when your dog hears your keys making contact with the key hole it means you are returning home.
So now that you know that dogs respond best to concrete concepts such as the names of objects or action words, it's time to put your dog to test and enroll him in a program that extends his vocabulary!