While dogs have long been hailed as “man’s best friend,” a recent study suggests that our furry companions might have a particular affinity for the higher-pitched voices of women.
Researchers from the Institute of Cognitive Neuroscience and Psychology at Eötvös Loránd University in Hungary conducted an intriguing analysis of brain scans to uncover that dogs truly pay attention when we communicate with them. What’s even more fascinating is that they seem to do so in a manner oddly reminiscent of human infants, displaying a preference for specific tones.
Infants are known to be highly receptive to “baby talk,” characterized by its high-pitched, sing-songy quality that tends to exaggerate vowel sounds. Studies indicate that this exaggerated speech may play a role in shaping a child’s developing brain in a positive way.
Unlike human babies, dogs aren’t exposed to human female voices in the womb, and high-pitched communication is not typical in dog-to-dog interactions. So, the question arises: why are dogs responsive to baby talk and higher-pitched speech?
THE METHOD
To delve into this mystery, the research team trained 19 family dogs of various breeds, aged between 2 and 10, to enter an fMRI machine and remain still for brain scans. While inside the machine, these dogs listened to three types of pre-recorded human speech: speech directed at dogs, speech directed at human infants, and speech directed at another human adult. The recordings featured both male and female speakers.
THE FINDINGS
The results were intriguing. Dogs exhibited greater activity in their auditory cortex when exposed to the exaggerated voices often used for pets or infants. This effect was especially pronounced when the speaker was female. Neuroethologist Anna Gábor from Eötvös Loránd University suggests that this could be attributed to the fact that women tend to use more exaggerated prosody, including elements like tone, stress, rhythm, and emotion, when communicating with dogs compared to men.
In the brain scans, human voices activated a part of the dog’s auditory cortex known as the temporal pole, as well as an area called the Sylvian gyrus, situated between the temporal lobe and the frontal and parietal lobes. These brain regions have also been observed to light up in human infants when exposed to baby talk.
Scientists have proposed two main hypotheses to explain this intriguing canine trait. One possibility is that there exists a fundamental and ancient sensitivity among mammals to higher-pitched and more variable frequency sounds. Alternatively, this trait may have been selected for during the domestication of wolves into dogs.
It’s conceivable that pre-domesticated dogs with a heightened sensitivity to dog-directed speech were more likely to stay close to humans and pay attention to vocal cues, fostering their domestication. Experimental evidence has shown that wolves are more responsive to lower-pitched speech, while dogs are more attuned to higher-pitched speech.
While this study involved a relatively small sample of 19 dogs and did not control for the sex of the pet owners, which could be an influencing factor, further research is warranted. Nevertheless, the similarities observed between how dogs and human babies respond to adult voices open up intriguing avenues for exploration. Our beloved pets may serve as a valuable model for understanding our own pre-verbal communication tendencies.
