Developmental prosopagnosiaProsopagnosia, sometimes called face blindness, may be present from childhood (called developmental prosopagnosia). Individuals with this type often do not realize until they are older that they are unable to recognize faces as well as other people do. Some researchers believe that developmental prosopagnosia may be inherited, since it appears to be present in more than one individual in some families. In 2005 German researchers found evidence of a genetic basis for the disorder by studying individuals with prosopagnosia in seven families.
It is also thought that developmental prosopagnosia is present in children with autism and Asperger syndrome. Children with these disorders have impaired social development, and prosopagnosia might cause or contribute to their difficulty in relating to other people.
Acquired prosopagnosiaAcquired prosopagnosia may occur after brain damage from head injury, stroke, or neurodegenerative diseases. Individuals with this type had normal face recognition abilities in the past, but this has been impaired or lost due to brain injury.
CausesThe neurological basis for prosopagnosia is not well understood. One theory is that it is the result of abnormalities, damage, or impairment in the right fusiform gyrus of the brain. It is thought that this part of the brain coordinates the neural systems that control facial perception and memory. Research has shown that the brain processes images of faces differently than other kinds of objects. There is some disagreement in the scientific literature about whether prosopagnosia is a general disorder of recognition or a face-specific problem. It may be that there are different types of prosopagnosia that have other symptoms in addition to difficulty with face recognition.
TreatmentIndividuals with prosopagnosia must learn other ways of remembering faces. Clues such as hair, voice, and clothes may help identify people. Awkwardness in social situations due to prosopagnosia may cause a person to become shy and withdrawn. Many individuals with the disorder report difficulty watching movies and television shows since they cannot identify the characters from one scene in the next. Researchers are working on ways to help individuals with prosopagnosia improve their face recognition.
Not so rare?Only about 100 cases of prosopagnosia have been documented in the worldwide medical literature. Scientists at the Prosopagnosia Reseach Centers at Harvard University and University College London are questioning whether the disorder is really that rare. They developed diagnostic tests, and in 2006 reported that after testing 1,600 individuals they suspect that 2 percent of the general public may have prosopagnosia. In 2004, researchers at the Institute for Human Genetics in Germany gave 576 biology students a prosopagnosia screening questionnaire; nearly 2 percent reported face-blindness symptoms.
Research participants neededIf you believe that you have prosopagnosia or another type of recognition impairment and are interested in becoming involved with research, complete the online form for the Prosopagnosia Research Centers.
- Harvard University. Tests for “face-blindness” reveal disorder may not be so rare. ScienceDaily.com press release dated 5/31/06, accessed at http://www.sciencedaily.com/releases/2006/05/060531094455.htm
- Henke, K., Schweinberger, S. R., Grigo, A., Klos, T., & Sommer, W. (1998). Specificity of face recognition: Recognition of exemplars of non-face objects in prosopagnosia. Cortex, vol. 34, pp. 289-296.
- National Institute for Neurological Disorders and Stroke. NINDS Prosopagnosia Information Page
- New Scientist. Face blindness runs in families. New Scientist, 26 March 2005.
- Prosopagnosia Research Centers. Prosopagnosia research.