Prosopagnosia is a symptom of brain injury in which brain injury survivors face acute difficulty in recognizing the faces of people (even including the faces of loved ones closest to survivors). A survivor with prosopagnosia may not even recognize his or her own mother’s face. In spite of this lack of recognition, this same survivor may easily recognize his or her mother’s voice or a distinctive item of clothing worn. Prosopagnosia is not a memory or visual deficit. A survivor with prosopagnosia can have good vision and strong memory in spite of this deficit. Survivors with prosopagnosia generally have little difficulty identifying various common objects. The issue sees sole expression in the recognition of faces.
Prosopagnosia most typically results from an injury to the right fusiform gyrus, inferior occipital gyrus and/or the superior temporal sulcus of the brain. These parts of the brain govern facial perception. Among their functions is to connect the parts of the brain that store names with those that store information about people. As such, a survivor may recognize parts of a person but have difficulty organizing those disparate parts into a single cohesive picture. As example, a recent TLC patient could identify one of her therapists because he wears a yarmulke (a Jewish religious hat), but could not recognize the rest of his face as belonging to that therapist. So if that therapist were to ever remove his hat, she would lose ability to visually recognize her therapist despite working with him several times per week. This deficit can limit function and cause stress in many areas of survivors’ lives. For example, it would be hard for a survivor to return to a job in sales if he or she could not recognize clients’ faces. Similarly, going to church could prove significantly awkward if the survivor could not differentiate between the face of the pastor and that of the pastor’s wife. Home life would suffer unique stress if a survivor could not differentiate between the faces of the survivor’s wife and the survivor’s mother. Interestingly, there are some people who are born with a developmental form of prosopagnosia. For instance, Jane Goodall the world famous researcher of chimpanzees had prosopagnosia. One of the most famous neurologists in modern times, Oliver Sacks, had prosopagnosia as well.
Many survivors notice improvement in their prosopagnosia as symptoms of their overall brain injuries improve. Progress of this nature tends to be more common in cases of a brain injury suffered on one side of the brain rather than on both sides of the brain. Compensatory strategies such as mentally attaching semantic information (e.g. a person’s job) to a person’s face and verbally describing facial features when practicing with faces (e.g. John has a big nose) have shown some benefit. Many survivors with prosopagnosia use other methods of identification (e.g. voice, unique gait, body type) instead of faces to identify others.
I hope this helped to explain some of the basics of prosopagnosia, a brain injury symptom that can cause significant problems in a survivor’s functioning.
Learn about brain injury treatment services at the Transitional Learning Center: http://tlcrehab.org/