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Dogs learn when they're sleeping and females do it better than males
I love watching dogs sleep. They seem totally at peace, and I always wonder what's happening in their dog brain and as their nose twitches, their eyelids flutter, they sometimes vocalize, and their legs move as if they're frenetically running here and there. Are they really chasing other animals when they're twitching or are they dreaming about their friends and their favorite foods? We really don't know. However, new research conducted by Ivaylo Borislavov Iotchev who works in the Department of Ethology at Eötvös Loránd University in Budapest, Hungary, and his colleagues shows that when dogs are sleeping they're actually likely learning something.
The results of this important new study are published in an essay called "EEG Transients in the Sigma Range During non-REM Sleep Predict Learning in Dogs," that's available for free online. It's not an easy read for non-specialists, however, it's easy to summarize what these researchers discovered. And, a good summary can be found in Virginia Morell's piece titled "Brain scans show dogs learn when sleeping—just like people."
Dr. Iotchev and colleagues studied 15 dogs who were trained to sit and lie down using English, rather than the Hungarian command they had previously learned. While they were sleeping, the researchers attached electrodes to the dogs' heads so they could record electroencephalograms (EEGs). They were paying particular attention to slow brain waves called "sleep spindles" that previously had been described but not quantified in dogs' brains.
The results of this study are very interesting. The researchers learned that the number of spindle sessions per minute was correlated with how fluent the dogs were in their new foreign language. While there weren't any age differences among the dogs, females showed a higher density of spindles and higher learning gain than males. Around one-third of the females learned the new words, whereas only around 10 percent of the males did.
The researchers also discovered that the density of spindles increased with learning gain. They also write, "An important implication of this work is that spindling frequency in dogs and humans could be more similar than previous estimates suggest."
All in all, it's reasonable to conclude that dogs, similar to other animals, learn when they're sleeping. Previous research on other animals, including humans, has shown that sleep spindles are a marker of sleep-dependent memory consolidation, and that some learning is taking place when individuals are sleeping, and the researchers note that
The non-invasive methods used in this research also are important to consider. The researchers note that they can be used in veterinary practices to diagnose what's happening in a dog's brain when it's necessary to have this information.
Let sleeping dogs lie
So, let sleeping dogs lie, and don't interfere in whatever they're dreaming about and learning. It's also a good time to catch up whatever else needs to be done when they're awake and romping here and there.
Please stay tuned for more exciting research in what's happening in brains when individuals are sleeping. There's more happening than meets the eye.
