Dr. Gregory Berns, a neuroscientist and professor at Emory University in Atlanta, decided to research the emotional intelligence of dogs. In order to do this, he needed to perform MRI scans on dogs while they were conscious.
Any of you who have ever had an MRI scan know the equipment is very loud, the space is very confined, and you have to remain completely still during the scan. Prior to Dr. Berns' work with his rescued black terrier Callie, a dog would have to be anesthetized to perform an MRI, but that would not permit the scientist to get the data he wanted. So Berns created an MRI simulator with a specially designed chin rest for dogs, and trained Callie to go inside. Once he got her regular compliance entering the equipment simulator, he got her used to wearing a headset to suppress the very loud noise and eventually she remained completely still for up to 30 seconds. What he discovered was that the part of the human brain that indicates enjoyment and positive emotions was extremely similar in the brain of a dog. Callie's brain reacted positively to the hand signal for food and to the sight of her owner. Along with Callie, a dozen other dogs were trained to be MRI certified and the results were similar. Berns' findings proved what we dog lovers have believed for years; that dogs are sentient beings capable of love and attachment.
For more information on his remarkable research read his book, "How Dogs Love Us": A Neuroscientist and His Adopted Dog Decode the Canine Brain."