Dogs Distinguish Between Human Emotions Including Negative Ones, MRI Study Finds

Researchers at the University of Vienna used functional MRI scans to examine how dogs process human facial expressions, publishing their findings in the journal iScience. The team trained 14 pet dogs, mostly border collies, to remain still and awake during ten-minute scanning sessions without restraint.

In a first experiment, eight dogs viewed happy or neutral unfamiliar human faces. Happy faces activated the temporal cortex and caudate nucleus, brain regions associated with higher cognitive processing and reward anticipation, similar to responses seen when dogs expect food or hear praise.

A second experiment with 12 dogs presented happy, sad, fearful and angry faces. The temporal cortex and caudate nucleus responded uniquely to happiness, while different brain areas activated when dogs distinguished between fear and sadness versus fear and anger.

No distinct neural difference appeared when dogs viewed sad versus angry faces, suggesting they may require additional cues such as body language to differentiate those emotions.

Study co-author Laura Cuaya, a neuroscientist at the University of Vienna, said this is the first demonstration that the dog brain can distinguish between emotions sharing the same negative valence.

The findings indicate dogs conduct more detailed emotional processing than previously documented, though the authors note the results may not generalize to all breeds given the predominance of border collies in the sample.

Psychologist Bridget Waller of Nottingham Trent University, who was not involved in the study, said the work highlights how domestication has shaped dogs' sensitivity to human social signals like smiling.

The researchers plan to adopt a more dog-centric perspective to understand how the animals integrate these brain signals to navigate the human world and to compare human and dog brain processing of the same emotional cues.