Do dogs prefer adult- or dog-directed speech? And do they favor hearing adult words spoken in dog-directed speech or dog words in adult-directed speech?
Speech directed toward infants, or 'baby talk,' has functional benefits. Higher pitch, altered prosody, exaggerated intonation, and content specific to infants help them learn and form emotional bonds with their caregivers. People in Western cultures often use a similar type of speech when addressing dogs, but is dog- or pet-directed speech functional? Investigators at the University of York in the United Kingdom conducted a study to analyze the responses of adult dogs to different types of speech to determine whether a functional relationship exists.
Two experiments were conducted. In experiment 1, adult dogs (n = 37) were placed in a room with 2 experimenters who played prerecorded audio of adult- and dog-directed speech. The speakers used to play the audio recordings, placed on the experimenters’ laps, were normalized for differences in decibels and distance from the dogs. The experimenters maintained neutral facial expressions and did not interact with the dogs during the experiment. Observers rated the reactions of the dogs, and data were analyzed using IBM SPSS software.
In experiment 2, the investigators sought to distinguish whether dogs had a preference based on prosody or content of speech. Adult dogs (n = 32) were played prerecorded audio of either dog-directed prosody with adult content or adult-directed prosody with dog content. Observers rated the dogs’ reactions. Mean, median, and maximum pitch were measured, and data were analyzed by generalized linear mixed models to evaluate the effects of prosody and content on the dogs’ behavior.
In experiment 1, dogs expressed a preference for dog-directed speech, as evidenced by the time spent looking at the experimenter during speech and in proximity to the experimenter following the speech (P < .005). In experiment 2, the dogs did not show a significant preference for dog-directed speech when content and prosody were not matched. Also in experiment 2, the dogs preferred the speech of one experimenter over another (P = .005) when dog-directed speech was played, but the same was not true when adult-directed speech was played. No significant difference was revealed with regard to proximity to the experimenters.
Results from the first experiment indicate that dogs prefer dog-directed speech; however, results from experiment 2 show that neither prosody nor content of dog-directed speech can explain the preference shown in the first experiment. The authors note that difficulty in producing dog-directed speech and adult-directed speech with altered content may have resulted in an inadequate representation of these types of speech in experiment 2; however, upon examination of the qualities of each recording, no significant differences were found.
Experiment 2 had fewer canine subjects, which may have affected the statistical analyses of the data. Dogs in experiment 2 showed a preference for one experimenter over another. It’s possible that appearance, smell, or some other quality of this experimenter was appealing to the dogs. Additional studies are needed to determine why dogs prefer dog-directed speech and whether it offers any benefits.
Dr. Bohn received her PhD and MS from Georgia State University and has been a practicing veterinary nurse for nearly 20 years. She provides freelance medical writing services through her business, Bohn Communications.