Agnosia is the loss of ability to interpret sensory input. A person with agnosia is still able to see, smell, or hear but cannot interpret what they are seeing, smelling, or hearing. For example, a person with perfectly good vision might lose the ability to recognize people. Thus agnosia is not a loss of sensory ability, but a loss of the ability to attach meaning to sensory messages.
What Causes Agnosia?
The most common cause of agnosia is a neurological problem, which may be induced by head trauma, stroke, or other brain injuries. When agnosia is caused by brain damage, the damage is typically in the occipital or parietal lobes. Some developmental disabilities may also cause agnosia.
Types of Agnosia
A person with agnosia may not lose the ability to interpret all sensory information. They might, for example, only struggle to recognize faces or letters. There are several sub-types of agnosia, including:
- Associative visual agnosia – The ability to classify types of objects without being able to say the object’s specific name.
- Prosopagnosia – The inability to identify faces of familiar people.
- Receptive amusia – The inability to hear music.
- Somatosensory agnosia – Difficulty with tactile stimulation. A person with this condition might not be able to conceptualize the texture of a familiar object.
Is There Treatment for Agnosia?
Agnosia is an extremely rare condition, and treatment focuses partially on remedying underlying causes. Some neurological abnormalities can be remedied with brain surgery, while agnosia from a stroke can be permanent. Occupational and speech therapy can help improve symptoms and lifestyle changes and supportive care can help people with agnosia learn to cope with their symptoms. Physicians may recommend that people with agnosia get sensory information through other senses, that others explain objects verbally to people with agnosia, or that people with agnosia institute organizational strategies to cope with their symptoms. However, there is no clear cure for agnosia at this time.
- NINDS agnosia information page. (n.d.). National Institute of Neurological Disorders and Stroke (NINDS). Retrieved from http://www.ninds.nih.gov/disorders/agnosia/agnosia.htm
Last Updated: 06-15-2018