You might, for example, respond, "fine," when a housemate asks how you're feeling, but if you are under the weather, your dog likely senses the change.
For the study, Andics and colleagues trained 11 dogs to lay motionless in an fMRI brain scanner. Human test subjects did the same. The researchers then monitored brain activity while the dogs and people listened to nearly 200 dog and human sounds, ranging from whining or crying to playful barking or laughing.
PHOTOS: Dogs In Combat
In dogs and humans, images show hearing a voice activates similar areas of the brain. The brains of dogs are more tuned to their own species. (I'll bet experience can change that. If a person spends a lot of time around dogs, for example, they will fine-tune their doggy perception skills. Dogs surely do the same.)
An interesting difference, noted in the study, is that in dogs, 48 percent of all sound-sensitive brain regions respond more strongly to sounds other than voices. That's in contrast to humans, in which only 3 percent of sound-sensitive brain regions show greater response to non-vocal sounds.