Now imagine waking up one day and not being able to recognize any of them.

Those with the condition are thereby forced to develop different ways of identifying people.

There are two types of prosopagnosia:congenitalprosopagnosia and acquired prosopagnosia.

Man sitting in a boardroom with a unrecognizable face

FangXiaNuo / Getty Images

Congenital prosopagnosia is not because of any structural differences in the brain or brain damage.

Some researchers believe that congenital prosopagnosia may beinheritedsince the condition tends to run in families.

Individuals with this pop in of prosopagnosia were previously able to recognize faces.

Research suggests they are unlikely to gain back this ability, though they may learn to compensate.

Causes

The neurological basis for prosopagnosia is not well understood.

For congenital cases, the cause might be related to genetics.

It may be that there are different types of prosopagnosia, each with their own set of symptoms.

Treatment

There are no cures for prosopagnosia.

Those with prosopagnosia must learn other ways of remembering faces.

Clues such as hair, voice, and clothes may help identify people.

Rehabilitation therapies may help with coping and working around the deficits.

Social situations may be awkward for people with prosopagnosia, causing them to become shy and withdrawn.

Therapy or medications may be able to treat anxiety or depression related to the condition.

Researchers are currently working on ways to help individuals with prosopagnosia improve their face recognition.

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National Institute for Neurological Disorders and Stroke.Prosopagnosia information page.

Dalrymple KA, Corrow S, Yonas A, Duchaine B.Developmental prosopagnosia in childhood.Cogn Neuropsychol.

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