How is face blindness diagnosed?

If the lack of eye contact and the problems with recognition are particularly pronounced in childhood, a medical and psychiatric clarification is carried out due to the parallels to autism mentioned above. If the children show normal emotional and social development, autism can be ruled out and the diagnosis of face blindness is made after other causes have been investigated. However, if the children are not particularly conspicuous, they can usually compensate their handicap well and face blindness may never be officially diagnosed.

Testing for so-called prosopagnosia (face blindness) is often difficult. The diagnosis is also not made on the basis of a standardized test, but by the attending physician’s assessment of the person’s symptoms and limitations. However, there is certainly a need for such a test, as face blindness is rather unknown even among physicians and is often misdiagnosed as an autistic disorder, especially in children.

Researchers are therefore developing questionnaires and image tests to clearly distinguish prosopagnosia from psychiatric disorders such as autism. In these procedures, for example, patients are shown the faces of famous personalities or close relatives on the computer, which are supposed to recognize them and describe the recognized characteristics. Face-blind people find it difficult to do this and focus more on features such as the hair or the position of the head instead of the actual face.

Unfortunately, such picture series are not always meaningful, because celebrities are recognized due to prominent features despite face blindness. More precise results are provided by pictures of unknown persons, in which the hairline, neck and the rest of the body have been cut away and therefore only the face can be seen. These photos are shown to the test persons several times and they should react if they recognize a face.

Face-blind people find it very difficult to do this and can only distinguish between people who have a different skin color or gender, for example.The facial features alone are therefore indistinguishable from these pictures of face-blind people. Nevertheless, such purely pictorial tests must always be supplemented by an expert consultation in which a doctor familiar with the clinical picture analyzes typical situations in everyday life, since other causes for the problems in facial recognition must be excluded. Thus, for example, the clarification of a visual impairment or other perception disorders are part of the test. Because people with prosopagnosia can perceive and describe the facial features of their fellow human beings without restriction, but they cannot assign any identity and thus cannot recognize them.