Subtle differences in human speech lost on dogs: Study

Many of us, especially the dog owners, share quite an extraordinary relationship with our canine companions. More often than not, we are under the impression that our dogs understand every word we say. 

But chances are, our dogs might not be hanging on to our every word, according to a new study published in the Royal Society Open Science journal on Tuesday.

Dogs have human-like auditory capabilities for interpreting speech sounds but dogs do not hear the subtle differences between words the same way humans do. 

Researchers at Eotvos Lorand University in Budapest measured family dogs' brain activity using electroencephalography, a technique that involves taping electrodes to the animals' heads.

Researchers at Eotvos Lorand University in Budapest measured family dogs' brain activity using electroencephalography, a technique that involves taping electrodes to the animals' heads Photo: CNN

The researchers played the dogs' recorded instruction words the canine research subjects already knew (such as 'sit'). 

However, similar but nonsense words (like 'sut') were also played to them. 

Researchers also played out very different nonsense words (like 'bep') to the dogs.

The experts discovered that dogs could tell the difference between the words they knew and the nonsense words. 

"The brain activity is different when they listen to the instructions which they know and to the very different nonsense words, which means that the dogs recognise these words," according to lead study author Lilla Magyari as published by CNN.

However, the study's trickier part revealed that the animals did not pay attention to the small differences between known words and similar-sounding words that do not have meanings ('sit' and 'sut.') 

The experts discovered that dogs could tell the difference between the words they knew and the nonsense words. Photo: CNN

Instead, according to the CNN report, the canine companions processed the words as the same, said Magyari, a postdoctoral researcher at the Department of Ethology at Eötvös Loránd University. 

Dogs have the extraordinary auditory capacity and the ability to hear words and sound, Magyari added, saying that dogs can differentiate speech sounds.

"But it seems like they don't pay attention to all of the speech sounds," she said, adding that further research could explain why.

"They may just not realise that all the details and speech sounds are really important in human speech," she further remarked.

While dogs may not recognise subtle differences in human speech and sound, the study confirmed that dogs listen and do not only respond to familiar humans or body gestures. 

"It shows that dogs can differentiate the words that they know from the utter nonsense words," Magyari said, noting that family dogs registered brain activity even when listening to the instruction words delivered by an unfamiliar voice through a speaker.