Agnosia is a rare disorder characterized by an inability to recognize and identify objects or persons. People with agnosia may have difficulty recognizing the geometric features of an object or face or may be able to perceive the geometric features, but not know what the object is used for or whether a face is familiar or not.
Agnosia can be limited to one sensory modality such as vision or hearing. For example, a person may have difficulty in recognizing an object as a cup or identifying a sound as a cough.
Agnosia can result from strokes, dementia, developmental disorders, or other neurological conditions. Agnosia can also occur suddenly after a head injury. It typically results from damage to specific brain areas in the occipital or parietal lobes of the brain. People with agnosia may retain their cognitive abilities in other areas.
Types and Symptoms
The types of agnosia are classified by the sense that is affected.
Visual aka apperceptive agnosia
This type results in difficulty recognizing familiar people or objects by sight. For example, you can be looking at a scrabble tile and a poker chip side by side but are unable to see the differences between them. Usually only one aspect of sight is altered. For example, although you are unable to recognize the poker chip, you can still describe the color, shape and size.
There are several subgroups of visual agnosia, including: agnostic alexia (inability to recognize text), prosopagnosia (inability to recognize familiar faces) and color agnosia (inability to discriminate between colors).
This is difficulty recognizing familiar sounds, such as a cough or rainfall.
There are three subgroups of this type of agnosia: auditory/verbal agnosia (inability to hear words), auditory agnosia (inability to hear environmental sounds, such as a dog barking), and receptive amusia (inability to hear music).
Tactile aka somatosensory agnosia
This is difficulty recognizing familiar objects by touch, even though their sense of touch has not changed. For example, if you pet a furry animal with your eyes closed, you would not be able to tell what you are feeling, but you may be able to describe how it feels.
Treatment is generally symptomatic and supportive. The primary cause of the disorder should be determined in order to treat other problems that may contribute to or result in agnosia. To schedule an appointment call 910-295-6868.
To Learn More visit: https://brainaacn.org/agnosia/
Content provided by the The National Institute of Neurological Disorders and Stroke (NINDS)