Dogs may possess a deeper understanding of language than previously believed, suggests a study published in Current Biology on March 22. The research indicates that pet dogs exhibit neural signs of surprise when presented with unexpected objects by their owners, implying their ability to form mental concepts of objects.
Ellen Lau, a neuroscientist at the University of Maryland in College Park, remarks that individuals familiar with dogs may not be entirely surprised by this revelation. However, Lau emphasises that the findings challenge the notion that dogs' comprehension of human speech is merely a reflexive response.
The study delves into the cognitive abilities of dogs, particularly those with average linguistic proficiency, rather than exceptionally gifted ones like Chaser, the border collie known for her extensive vocabulary. Marianna Boros, a neuroscientist and ethologist at Eötvös Loránd University in Budapest, and her team aimed to understand how dogs perceive and process verbal cues.
The researchers recruited 27 pet dogs and their owners for the study. While brain data for only 18 dogs were analysed, the diverse group included breeds such as toy poodles, Akitas, Labradors, and mixed breeds. Owners were asked to bring five familiar toys to the lab, where electrodes were attached to the dogs' heads.
During the experiment, the dogs listened to recordings of their owners' voices accompanied by phrases like, "Kun-Kun, look, the ball!" Simultaneously, an electronic window with adjustable transparency allowed the dogs to observe their owners holding different toys, including balls and ropes.
Brain activity was monitored using electrodes while the dogs listened and observed the window. The researchers observed a larger-than-normal signal, indicative of surprise, when the dogs encountered unexpected objects, such as a rope instead of a ball. This signal, akin to the N400 effect observed in humans, suggests that dogs form mental expectations based on verbal cues.
Marianna Boros emphasises that while the presence of this neural signal may not be surprising, it offers valuable insights into the mental processes of dogs. The findings suggest that dogs understand more than they outwardly express, providing a glimpse into their complex cognitive abilities.