Prosopagnosia- Face blindness in a Nutshell
Ms. Angela Shony,
St. Xavier's College (Autonomous),
Mumbai, Maharashtra, India
Imagine waking up one sunny morning and not being to recognize faces! Imagine bumping into someone looking like you thinking it was you in the mirror.
Is this possible? How can one not recognize faces - the basic form of identification for humans. The answer is- YES it is possible due to a neurological disorder called PROSOPAGNOSIA. It is not like other neurological disorders related to memory loss, vision impairment, etc. It is described as the inability to recognize faces or unable to recognize familiar faces. Well, in simple words we can say it is face blindness where the individual cannot recognize or differentiate faces of their friends, people that they have just met, their family in severe condition; no matter how good vision or memory they have. According to WHO, 2.5% of the population that is 1 in every 50 people are detected with this rare condition. But recent studies make it clear that this it is getting more common than before. To make it simpler for them to identify the person they always keep a relatable cue- hairstyle, diction, voice, etc. But if one of these cues is changed for example the hairstyle then it is difficult for the individual with prosopagnosia to identify. Not everyone with prosopagnosia realizes that they are one of them. Prosopagnosia being something that not everyone is aware of makes it difficult or rather let’s say there is not enough research done.
Let us first understand how our brains recognize faces. Processing faces works differently than processing other things we see. When we look at something our eyes take visual information through the retina and send it to the occipital cortex. Where it goes from there depends on what you are looking at. With faces, multiple areas seem to be responsible for the processing.
Primarily Inferotemporal cortex, Fusiform face area(FFA), Occipital face area(OFA), Superior Temporal Sulcus(STS). They are each involved in slightly different functions that together help us process faces. The OFA seems to be involved in recognizing the parts of faces like nose, mouth, or eyes. Whereas the FFA seems to configure these parts to help us figure out if it’s a face or not. Once we know that it is the face, the STS seems to help us determine our emotions. Whether the person is happy, sad, or angry. It also seems to help us read lips to help us determine what's being said, but in the case of a person with prosopagnosia, faces aren't processed like any other object. This can be the result of a brain injury like a tumor, stroke, degenerative illness, or a traumatic head injury that affects the FFA. This is called Acquired prosopagnosia. When there is damage or impairment caused due to the injury or hereditary in the right fusiform gyrus of the brain it gives rise to prosopagnosia (poor facial recognition or no recognition at all). Others have developmental or congenital prosopagnosia that is by birth as a baby they don't develop the normal face recognition ability, which is due to genetics (hereditary).
The very first case of prosopagnosia came 150 years ago. This term was not known until a German neurologist Joachim Bodamer studied his patient who was treated for a bullet wound in his head in 1947. Later impaired face recognition was seen in wounded soldiers.
It is comparatively very difficult for individuals born with prosopagnosia than the ones who developed this condition after brain stroke or injury. Since the individuals with prosopagnosia by birth don't know what a face looks like or what facial expressions are like. They mostly find it difficult to get along with the crowd like in schools, workplaces, etc. Whereas for adults it is not easy to live with such a disorder but they look for cues that make things easier for them. It is common for such individuals to develop a social anxiety disorder, depression since they can't recognize their faces in the mirror.
For diagnosis, the neuroscientist or the neurologist shows few familiar faces and asks them to recognize them later again. Other assessment includes tests of face perception like spotting the difference in the faces, judging the facial expression, age, etc. The Dartmouth Face Perception Test specially designed for children. As for the treatment, there is none in the present. But studies are being carried out all over the world. The concept of developmental prosopagnosia is less clear than the acquired prosopagnosia.
Being face blind means living in a world brimming with outsiders. The way that a portion of individuals is colleagues and even companions is no comfort. At the point when your mind won't let you perceive individuals, how would you explore the world? But, until further notice, individuals with fluctuating levels of face visual deficiency must depend on their own resourcefulness, beginning with instructing others about their bizarre, yet not uncommon, condition. Progressively, prosopagnosia is likewise the subject of books, Web destinations, and care groups, where individuals with face visual deficiency or geographical agnosia can share encounters and, no less significant, systems for perceiving countenances and places when the standard thing "programmed" components have been hindered.
Can exercise or medicines improve prosopagnosia? Currently, there are few remedial attempts for acquired prosopagnosia, but most of its outcome was not as anticipated. Many notable individuals amongst us like Chuck Close, Dr. Oliver Sacks, Dr. Karl, and many more are all prosopagnosic. Maybe one day the scientists will be able to unveil the reason for the occurrence of this disorder.
Reference:
1) Defining face perception area in the human brain by Bruno Rossion, Bernard Hanseeuw, Laurence Dricot - https://pubmed.ncbi.nlm.nih.gov/22330606/#:~:text=Abstract,been%20identified%20in%20neuroimaging%20studies.&text=A%20BOLD%20latency%20mapping%20analysis,compared%20to%20all%20other%20areas.
2) Prosopagnosia: current perspective Sherryse L Corrow,1,2 Kirsten A Dalrymple,3 and Jason JS Barton1,2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5398751/#:~:text=In%20acquired%20prosopagnosia%2C%20poor%20face,face%20recognition%20in%20wounded%20soldiers.
3) Understanding the functional neuroanatomy of acquired prosopagnosia Bettina Sorger 1, Rainer Goebel, Christine Schiltz, Bruno Rossion - https://pubmed.ncbi.nlm.nih.gov/17303440/
5) A Face to Remember | The Scientist Magazine https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.the-scientist.com%2Fcover-story%2Fa-face-to-remember-36508&psig=AOvVaw2JjlIdGGH5pPU4oqJY0y7E&ust=1604301717806000&source=images&cd=vfe&ved=0CA0QjhxqFwoTCKjQoeLn4OwCFQAAAAAdAAAAABAJ