Psychology and Minds
Written by Alfonso Elizondo
Several decades ago the eminent American psychologist, Paul Eckman, came up with the idea that there are six basic human emotions. These are sadness, happiness, fear, anger, surprise and disgust. However, a recent scientific study published in Current Biology and conducted by researchers at Glasgow University in the UK concludes that there are not six basic human emotions but only four.
These findings came from observing the different facial muscles, which the researchers have called 'Action Units,' as well as the time-frame during which each muscle contracts or relaxes. Although this study has been a great start in the objective study of the expressions of the human face, there is no doubt that more research dynamics will emerge, thanks to these analysis platforms developed by the University of Glasgow.
Researchers from that University’s Institute of Neurosciences and Psychology think that although the facial expression signals of happiness and sadness are distinct across time, fear and surprise share a basic signal, with the eyes being wide open at the beginning when both expressions are generated. Similarly, disgust and anger have the common symptom of the wrinkled nose during the first moments that they are transmitted, which could be the vestiges of an ancestral signal of primitive human beings when they were in danger.
According to independent researcher Rachael E. Jack, the results are consistent with evolutionary predictions. In other words, facial signals are designed by both biological and social evolutionary forces in order to function more appropriately at the time of their occurrence. Rachael E. Jack also says that the signals of reaction to danger give an advantage to the human being, facilitating a quick reaction. In addition, the wrinkled nose prevents harmful particles floating in the air from entering the body of the human being who is in danger, while the eyes wide open increase the perception of visual information that will then be used to flee.
With the passing of many generations, according to how humans moved around in the space on the Planet, socio-ecological diversity led to the specialization of certain facial expressions that were previously common to all humans, but became varied according to the different ethnic groups and cultures.
A new state-of-the-art technology has emerged to analyze the facial movements involved in emotions. Software called Generative Face Grammar, developed by Philippe Schyns, Hu Yu and Oliver Garrod, used cameras to capture a three-dimensional image of the faces of persons who had been trained to mobilize the 42 facial muscles independently. With this information, a modern computer can generate specific or random facial expressions on a three-dimensional model based on the activation of different Action Units to reproduce any facial expression.
Those who participated in these studies were asked to observe the three-dimensional model as it showed different facial expressions, noting which emotion was being expressed on each occasion. And the researchers differentiated the concrete Action Units that the participants associated with a specific emotion in each case. Through this analysis they discovered that the facial signals of fear / surprise and anger / disgust were confused at first and became recognizable a few moments later when other Action Units came into play.
Apparently, the scientists who did this research plan to develop this line of study of facial expressions in different cultures, including East Asian populations, which, according to some scholars, interpret some of the classic emotions differently, emphasizing the movements of the muscles of the eye instead of those of the mouth as in the West.
Addendum: These new findings will have to be compared in different cultures to be able to determine with any degree of certainty the facial gestures that are associated with certain emotions.