Although hunger, pain, anger and fear are the main reasons that can make a newborn cry, parents cannot easily recognise which emotion is the cause of the tears.
Now, Spanish researchers have found that eye movement and the dynamic of the cry can tell the emotion causing the baby to cry.
“Crying is a baby’s principal means of communicating its negative emotions and in the majority of cases the only way they have to express them,” Mariano Choliz, researcher at the University of Valencia, explained to SINC.
Chpoliz participates in a study along with experts from the University of Murcia and the National University of Distance Education (UNED) which describes the differences in the weeping pattern in a sample of 20 babies between 3 and 18 months caused by the three characteristic emotions: fear, anger and pain.
In addition, the team observed the accuracy of adults in recognising the emotion that causes the babies to cry, analysing the affective reaction of observers before the sobbing.
According to the results, the main differences manifest in eye activity and the dynamics of the cry.
“When babies cry because of anger or fear, they keep their eyes open but keep them closed when crying in pain,” stated the researcher.
As for the dynamic of the cry, both the gestures and the intensity of the cry gradually increase if the baby is angry. On the contrary, the cry is as intense as can be in the case of pain and fear.
The adults do not properly identify which emotion is causing the cry, especially in the case of anger and fear.
Nonetheless, “although the observers cannot recognise the cause properly, when babies cry because they are in pain, this causes a more intense affective reaction than when they cry because of angry or fear,” outlines Choliz.
For the experts, the fact that pain is the most easily recognisable emotion can have an adaptive explanation, since crying is a warning of a potentially serious threat to health or survival and thus requires the carer to respond urgently.
When a baby cries, facial muscle activity is characterised by lots of tension in the forehead, eyebrows or lips, opening of the mouth and raised cheeks. The researchers observed different patterns between the three negative emotions.
As Choliz notices, when angry the majority of babies keep their eyes half-closed, either looking in apparently no direction or in a fixed and prominent manner. Their mouth is either open or half-open and the intensity of their cry increases progressively.
In the case of fear, the eyes remain open almost all the time. Furthermore, at times the infants have a penetrating look and move their head backwards. Their cry seems to be explosive after a gradual increase in tension.
Lastly, pain manifests as constantly closed eyes and when the eyes do open it is only for a few moments and a distant look is held. In addition, there is a high level of tension in the eye area and the forehead remains frowned. The cry begins at maximum intensity, starting suddenly and immediately after the stimulus.
The results published recently in the ‘Spanish Journal of Psychology.’