A new Hungarian study published in the journal Current Biology has discovered through MRI that brains of dogs and humans respond similarly upon hearing vocal cues such as crying and laughter.
To produce a quality MR image, the person (or animal!) must be able to lie completely still within the scanner. 11 pet dogs participated in the study, dogs who needed to be trained to take the common canine command "Lie down," to the next level--complete stillness for as long as it would take to perform the study's tests. "There were twelve sessions of preparatory training, then seven sessions in the scanner room, then these dogs were able to lie motionless for as long as eight minutes," says Dr. Attila Andics of the Comparative Ethology Research Group at the Hungarian Academy of Sciences, and lead author of the study. "Once they were trained, they were so happy, I wouldn't have believed it if I didn't see it."
The researchers also scanned the brains of 22 humans, for comparison.
While in the scanner, both the dogs and humans were played 200 sounds ranging from dog sounds, human vocalizations (without words) and environmental noises like the sound of traffic. The researchers found, in both dogs and humans, that the temporal pole (the most anterior part of the the brain's temporal lobe) was activated. Highly emotional sounds, such as crying or laughter, lit up a brain area near the primary auditory cortex again, in both the humans and the dogs. "The location [of noted activity] in the dog brain is very similar to where we found it in the human brain," says Dr. Andics.  "The fact that we found these areas exist at all in the dog brain at all is a surprise - it is the first time we have seen this in a non-primate."
The researchers are getting set to continue similar experiments, starting with reactions in the canine's brains to specific words.