The ability to recognize faces is a unique and rather difficult neurocognitive skill to learn that has significant social implications. It's pretty embarrassing to meet a smiling and waving person in the park and not recognize him by sight. Everyone can forget from time to time where he saw a passer-by who greeted him before. But only 2% of the world's population face this problem every day and cannot even recognize good acquaintances, friends and relatives.
This disorder is called prosopagnosia or facial agnosia. The faces appear the same to people with this condition. The traditional view of this problem assumes that facial blindness is due to visual impairment. However, people with prosopagnosia do an excellent job of visual identification tests on various objects. The paradox attracted scientists for many years, until researchers at Harvard Medical School in Boston became convinced that the inability to recognize a neighbor in the country or a colleague was associated with difficulties in extracting information from memory.
Joseph DeGutis, lead author of the work published in the journal Cortex, believes that people with prosopagnosia cannot remember the contextual data about a person: name, profession, marital status, hobbies. In case of chance encounters with acquaintances in the park, in the minds of the blind, only a vague sensation of acquaintance arises in the minds of the blind, without any details in the memory. Can you trust this feeling?
Scientists set up an experiment in which 60 people, aged 18 to 65, participated. Half of the volunteers suffered from facial blindness throughout their lives. Each participant was shown 60 images of unfamiliar faces. The images were then shown again, but added to the set of 60 new images. The volunteers classified the faces as previously seen or meeting for the first time.
Participants without prosopagnosia performed better as expected. However, people with blindness could correctly identify many of the faces they saw in the first part of the experiment, albeit with less certainty. Therefore, scientists believe that the mechanism of face recognition in ordinary people and those who suffer from prosopagnosia not only differs in the ways of working with memory, but there is something deeper than a vague sense of familiarity, which helps the blind in faces to still recognize them.
The results of the scientists are an important step towards improving the lives of prosopagnosia sufferers. In addition, the work has brought researchers closer to a fuller understanding of memory processes and how they relate to visual perception.