From the moment of birth, we are surrounded by faces. Relatives, friends, colleagues; happy, sad, young, old, attractive, frightening faces; with a new haircut, glasses, without beard, after 25 years etc. Even with all these features changing constantly, we can easily recognise our acquaintances in any crowded place. Although quickly analyzing the numerous features present on a face, and recognising faces and the characteristics belonging to them means no difficulty for most of us, it is still a challenge do build a face recognition software similar in efficiency and capacity to human face processing. How face recognition works in humans is not just a theoretical question for machine vision and psychology researchers, but also an everyday practical difficulty for some of our fellow people. Face blindness, or prosopagnosia is one of the most interesting neuropsychological disorders from a research perspective, and one of its – rare but severe – forms can be present form birth, without any neurological injury. Developmental prosopagnosia affects at least two out of 100 people according to the latest results. According to the “law of large numbers”, if you have 300 friends on social media sites, it could mean that 5-6 of them might not recognize you, if you ran into each other on the street. But why is that?
How come you did not realize this yet, or how do they “keep their difficulty a secret”? You may learn a lot about this, and about the disorder in general through our informative materials. On the Compensations page you can read about social difficulties of face-blind people, including recognising their closest relatives or sometimes even themselves. By examining the neural mechanisms behind face recognition difficulties, we could get closer to understanding normal face recognition processes as well. Understanding the psychological and neural background mechanisms and developing possible treatment opportunities is especially important, since research results suggest that congenital prosopagnosia might be hereditary.
That is, prosopagnosics are able to recognise objects, the difficulty only comes with faces, or with categorization processes related to faces (e.g. gender, emotion, identity, attractiveness, similarity, mouth movement etc.).
The first description of the disorder comes from Bodamer (1947), who examined three II. World War veterans. One of them was not even able to recognise his closest acquaintances, but he immediately recognised Hitler, because of his unique hairstyle and mustache.
Oliver Sacks did the most to raise public awareness about prosopagnosia by publishing a book titled The Man Who Mistook His Wife for a Hat, in which one of his patients confused his feet for his shoes, also he could not recognise his wife and students by their faces, only by their voices and gait. Although Sacks’ famous patient mistook his wife for a hat, most of prosopagnosics have an intact face discrimination ability; they can separate faces from objects, but they are unable to decide to whom the face belongs to. The patients described by Bodamer, Sacks and others show similar symptoms, but the background mechanisms can be entirely different.
Prosopagnosia derives from a selective injury or dysfunction of the brain’s visual system, especially of lower temporal/occipital cortical areas, the FFA (fusiform face area) and OFA (occipital face area).
Prosopagnosics, who have not suffered any brain injury through the course of their lives mostly suffer from a face recognition problem from birth. This type of the disorder is referred to in literature as developmental prosopagnosia.Through the last decade, several studies have examined the perceptual abilities of persons suffering from face recognition disorder, and tried to understand the normal face perception process through this deficit. In our lab, we aim to develop new methods and experimental designs to contribute to the understanding of normal face perception. To achieve this, it is essential for us to be able to study persons who have face recognition problems as well. This website is developed to inform people about the face recognition disorder; or if You feel like having problems with recognising people, or on the contrary, feel like having really good face recognition skills, You can contact us here.
Complete our online questionnaire and provide your contact details; after reviewing the answers we will inform you of the results. If it is likely that You are prosopagnosic, we provide the opportunity of a detailed examination in our lab free of charge, where we map the type and exact parameters of the disorder, and prepare a personalised feedback of your performance. In case You would like to test your face recognition performance online, sign up here, and complete our tests!
Thank you for your cooperation.