Sunday, August 9, 2009

Smart Dogs, Smarter Babies

"Your dog may be smarter than your toddler" screams the headline in CNN. Can it be true? What kinds of intelligence do dogs display? And what does it have to do with child language development?

Well, there are two claims made in the article. One finding is that dogs understand about 180 words, signs, signals and gestures. How does this compare to young children? Toddlers between 18 and 24 months on average can produce about 180 different words (note that these are averages, children are very idiosyncratic at this age and so their vocabulary size can vary a lot). We would expect children at this age to use at least 50 different words (so, you can see how much variation there is). But, children may UNDERSTAND many MANY more words than they use. By this same age (18 months), they should understand about 300 or more words. By age two they understand even more. So, it looks like here toddlers know MORE words than dogs.

The other thing I found interesting in this article is that dogs seem to be able to recognize number of items. The way this experiment was done is very clever. This is because dogs can't tell you how many they see (neither can very young children). But, they can tell you if the number of treats they expected in their bowl is not what they got. How? Well, the person doing the experiment dropped treats into a bowl for the dog one at a time. But, they either took out or added treats while the dog was not looking. When the number of items matched the number of items the dog saw put into the bowl they went straight to eating it. When the number expected did not match the actual count, the dog paused for a moment. This pause time difference was a way that experimenters were able to infer that the dogs had noticed the change in number.

Similar experiments have been done with babies. In one experiment, researchers showed babies arrays of dots. Babies as young as 6 MONTHS could tell the difference between 2 and 3 dots. As in the dog experiment, babies couldn't just tell the examiner how many they saw, but they experimenters could tell by how long they babies looked at the arrays that they could tell there was a difference. At this age however they did not notice the difference between 4 and 6 dots-- they looked at those arrays the same amount of time. Again this is an age much younger than 2 or so.

So, all in all, dogs do have some surprising abilities. But babies language and math abilities are better. Enjoy!