SIX-MONTH-OLD babies are able to connect both visual and auditory information to recognise emotions.

That’s according to a new study based on research from the University of Geneva (UNIGE), Switzerland.

Scientists measured the ability of six-month-old babies to make a connection between a voice (expressing happiness or anger) and the emotional expression on a face (again, of happiness or anger).

They found that babies look at an angry face – especially the mouth – for longer if they have previously heard a happy a voice.

This reaction to something new demonstrates for the first time that babies have an early ability to transfer emotional information from the auditory mode to the visual.

Babies can distinguish happiness from other expressions which suggests they possess early skills for differentiating between emotions.

Twenty-four 6-month-old babies were exposed to voices and faces expressing the emotions of happiness and anger and eye-tracking technology was used to measure the babies eye movements with great precision.

In the first phases the babies faced a black screen and listened to a neutral, happy or angry voice for 20 seconds.

In the second stage, the babies were placed in front of two emotional faces, one expressing happiness and the other anger.

The research team were then able to determine whether the time spent looking at one or other of the emotional faces – or specific areas of the face (the mouth or eyes) – varied according to the voice they listened to.

If the babies looked equally at both faces, it would not be possible to conclude that there was a difference.

Amaya Palama, a researcher at the Laboratory of Sensorimotor, Affective and Social Development in UNIGE’s Faculty of Psychology and Educational Sciences said, “On the other hand, if they clearly looked at one of them much longer, we could state that they are able to spot a difference between the two faces.”

The results of the study revealed that six-month-olds did not have a preference for either of the emotional faces if they had already heard a neutral voice or a voice expressing anger.

On the other hand, they spent longer looking at the face expressing anger – especially its mouth – after hearing a voice expressing happiness.

This visual preference for novelty shows babies ability to transfer emotional information about happiness from the auditory to the visual mode.

The findings were published in the journal PLOS ONE.