Dogs have been in close contact with humans for thousands of years. Estimates range from 9,000 to 30,000. Due to this long association dogs are thought to have the ability to not only understand but to communicate with humans. Many researchers in this field attribute these communication skills to the manifestation of unique traits that enables dogs to be acutely sensitive to cues supplied by their humans.
Recent research in canine cognition has shown considerable variability, depending upon the design of the experiment(s) and probably the agenda of the person(s) doing the research but it seems clear that at least some dogs can and do follow pointing and gaze cues, can fast map novel words and according to some studies have emotions. Since they cannot communicate with us with spoken language researchers have mostly had to closely observe behavior in a wide variety of experimental designs and infer how the canine brain functions by speculation.
Now we can use functional magnetic resonance imaging (fMRI) to study brain function. Gregory S. Berns, MD, PhD is a neuroscientist and director of the Center for Neuropolicy at Emory University. He recently published a book entitled: HOW DOGS LOVE US: A neuroscientist and his adopted dog decode the canine brain. He describes in this book and in articles published in scientific journals how his group trained dogs to lie still in the MRI machine while fully awake and found that the reward-prediction error hypothesis of the dopamine system provided a concrete prediction of activity in the ventral caudate of the dogs studied, i.e. the dogs were able to respond to specific hand signals associated with either giving a food reward or withholding it. During the experiment the dogs were not given the reward, just the hand signals they had been conditioned to. The results demonstrated the specific areas of the brain that anticipated the pleasurable reward. These same brain locations have been associated with dopamine release in many studies conducted in awake humans and primates. There was significantly less dopamine sensitive response when the withholding reward signal was given. The interpretation of these results indicates the dogs brains responded THINKING they were going to receive the treat.
Dr. Berns and his research group believe they can extend these studies to characterizing many questions about our ability to communicate with dogs including their ability to respond to human facial expressions and how dogs process our spoken words. Perhaps we are on the verge of understanding how dogs respond to our emotional state and perhaps if and how they grieve for a lost loved one. Maybe we can even find out if they really do love us or just manipulate us so we will feed them.