Many cat owners swear their furry friends always know exactly what they are thinking, but a new study suggests that this couldn’t be further from the truth.
Researchers found that felines can’t understand human voices, and think all our various vocalisations sound exactly the same.
While cats do react to humans’ emotional outbursts, they don’t seem to be able to distinguish those emotions.
That means your cat likely thinks your laughter, sobs, screams, and shouts all sound pretty much identical.
Almost all domesticated animals, from dogs to goats, have developed some ability to react to the emotional tone in a human voice.
Yet, while human voices almost always put the cat in a state of heightened alertness, the emotion behind the noise made absolutely no difference.
The researchers, therefore, suggested that cats aren’t able to distinguish humans’ moods by listening to their voice alone.
Likewise, the scientists found no evidence that cats process different emotions in different parts of their brains – as dogs and horses are able to.
While cats do react to humans’ emotional outbursts, they don’t seem to be able to distinguish those emotions when they come from a stranger
Cats don’t process the difference between shouts, screams, sobs, or laughter, a study has found. They just become moderately stressed (middle) regardless
Just like most domesticated animals, cats do have a striking ability to react to human emotions.
However, previous studies have only looked at how cats respond to human facial expressions and body language.
The researchers wanted to understand whether cats could identify the four basic emotions – fear, anger, happiness, and sadness – by the clues in our voices alone.
Scientists tested 20 different house cats in the comfort of their own homes with various pre–recorded vocalisations.
As a clip of a sob, scream, laughter, or shout played, researchers carefully watched the cats to judge their reactions.
Paying close attention to their movement, posture, eyes, ear position, and tail movement, the scientists were able to see how stressed the cats became.
Remarkably, cats almost always entered a state of medium stress when hearing a human vocalisation – marked by sideways ears, dilated pupils, and a twitching tail.
However, the cats entered this same state of stress regardless of what clip they heard.
| Relaxed | Moderate Stress | Severe Stress | |
|---|---|---|---|
| Movement | Eating or walking calmly | Self–biting or jumping on furniture | Running away or hiding |
| Posture | Sitting or standing with body relaxed | Sitting or standing with tension | Crouched |
| Ear Position | Neutral | Sideways | Rotated backwards |
| Eyes | Narrowed | Dilated pupils with normal open eyes | Eyes wide open |
| Tail Position | Vertical or wrapped | Twitching tail tip | Tail held down or swishing |
To learn more, researchers also paid close attention to which way the cats turned their heads.
This is key because it can reveal which side of the brain an animal is using to process a particular sound.
Lead author Dr Serenella d’Ingeo, of the University of Bari Aldo Moro, says: ‘In many vertebrates, the right hemisphere is generally more involved in processing highly emotional or potentially threatening stimuli, whereas the left hemisphere is more involved in processing familiar social signals and routine communication.
‘By observing the direction of the first head turn, researchers can infer which hemisphere is preferentially engaged by a particular sound.’
For example, studies have shown that cats will turn their head to the right when they hear purring, which is processed in the left hemisphere.
Meanwhile, cats will turn their heads to the left more often if they hear frightening sounds like barking, processed in the right hemisphere.
But when the cats in the trial were played the sounds of human emotions, they didn’t show a preference to look in either direction.
Dr d’Ingeo says this suggests human vocalisations aren’t seen as ‘sufficiently informative’ to be processed in a specific hemisphere, unlike the very informative sounds of other cats.
Cats generally became moderately stressed regardless of what they heard. Researchers suggest they may prioritise the intensity of emotional arousal rather than the specific emotion
However, the researchers stress that this doesn’t mean cats can’t tell human emotions apart.
In fact, studies have shown that our feline companions are very sensitive to the emotional states of their specific caregivers.
This suggests that the quality of the human–cat relationship might determine whether or not a cat understands what a person is saying.
When they hear their own owner’s voice or have body–language and facial cues to pair the sound with, cats will process the specific emotion.
But when the voice is unfamiliar, the researchers suggest that they prioritise the intensity of feeling being conveyed rather than the specific emotion.
The researchers suggest that cats may prioritise the level of emotional intensity conveyed by the voice rather than the specific emotion itself.
‘Rather than immediately distinguishing between happiness, fear, anger or sadness, they responded with a generalised increase in alertness, which may represent an adaptive strategy preparing them to react rapidly to a potentially relevant social situation,’ says Dr d’Ingeo.
The researchers say that cats might have initially evolved this response as a survival strategy in the wild before adapting it for domestic life.
Researchers found that cats had no preference for which way to turn their head, which suggests they are not processing different emotional vocalisations with different parts of their brain as dogs do
As an animal that can be both predator and prey, cats have to be incredibly responsive to the environment around them.
That means their brains might prioritise reacting to a potential threat before figuring out exactly what it is.
In a social setting, that same response means getting ready for a rapid reaction when confronted with an unfamiliar person.
As to why cats process voices so differently from dogs and horses, researchers say the secret once again lies in their evolutionary past.
While some animals live in naturally stable groups, cats are ‘facultatively social’, meaning whether they form social groups depends on factors such as resource availability, early experience, and individual predisposition.
Those very fundamental differences in social behaviour may have changed the way that cats’ brains process our voices.
Dr d’Ingeo explains: ‘Because dogs and horses have evolved in more stable social systems, they may be better adapted to extracting detailed emotional information from unfamiliar individuals.
‘In contrast, cats may adopt a more cautious strategy, responding first with increased vigilance rather than immediately differentiating between emotional states.’



