Horses can read human emotions by correlating facial expression and tone of voice, research suggests.
The discovery follows previous findings that herd animals such as horses are good at communicating emotional states between each other.
For the new study, scientists adapted a technique used to assess mental development in infants.
Horses were shown screen images of happy or angry human faces, and at the same time listened to recordings of praising or scolding voices.
Sometimes the image matched the sound, and at other times it did not.
The results, reported in the journal Scientific Reports, showed that horses reacted twice as fast when they were surprised by a voice and face at odds with each other.
The animals’ response to an “expectancy violation” suggests that they are able to integrate facial expressions and vocal tones to perceive human emotions, said the scientists.
Lead researcher Dr Ayaka Takimoto, from Hokkaido University in Japan, said: “Our study could contribute to the understanding of how humans and companion animals send and receive emotional signals to deepen our relationships, which could help establish a better relationship that emphasises the well-being of animals.”