Forget CAT scans; dog scans show canine brain activity

Its long been known that dogs want to please their owners. Now researchers are using that desire to train dogs to lie still in fMRI machines to measure brain activity while the dogs are awake. (Photo: File/ Mickael Boyer).

Researchers from Emory University are, for the first time, looking inside the brains of domesticated dogs using functional Magnetic Resonance Imaging (fMRI).

fMRI is a technique that uses changes in blood flow in different areas of the brain as a correlate for changes in activity in those regions. It has been used extensively to explore the minds of human participants as they perform tasks, solve questions, or think about certain things. But most animals must be anesthetized or immobilized in order to be scanned in an fMRI machine. This new study takes advantage of dogs' eagerness to please their owners - dogs can be trained to get inside the machine and perform simple tasks while holding their heads still.

Gregory Berns and his co-authors published the results of their first canine fMRI experiment in PLos One, demonstrating the methods used to train the dogs. Two dogs were involved in this experiment. Both underwent months of training with positive reinforcement  to walk into the fMRI scanner. They were taught to hold their heads still on a chin rest during the scans so researchers could take clear pictures of their brains. The dogs also had to get accustomed to wearing earmuffs, to protect them from the noise of the scanner.

In this experiment, the dogs were trained to respond to hand signals given by their owners. One signal indicated the dog would receive a hot dog, and another signal indicated no hot dog was to be given. In both dogs, the caudate region of the brain was activated when the hot dog signal was given, but not the other signal. In humans, the caudate is associated with rewards. The results are not surprising. What's more important is this paper demonstrates the feasibility of scanning awake, unrestrained dogs in an fMRI machine.

Berns and his colleagues hope this initial demonstration of the technique will lead to many more experimental questions about how dogs think and how they communicate with humans. Dogs and humans certainly have a unique evolutionary relationship. Dogs were likely the first animals to be domesticated by humans, between 10,000 and 30,000 years ago. And new research suggests dogs may have allowed Homo sapiens to out compete Neanderthals, dwindling the later to extinction.

Ultimately, Berns and his colleagues want to know scientifically what many dog owners think about every day: What is my dog feeling? Does my dog feel empathy? How much of what I say to my dog does he understand?