R48: Dyslexia and other symbolic dysfunctions, not elsewhere classified

R48.1: Agnosia

We use our senses to perceive our environment. Certain areas of the brain process particular sensory impressions. As a result, we can recognize symbols or identify sounds, for example.

Problems with detecting sensory impressions can vary widely. For example, we may be able to detect sounds but not identify them. Or we might be able to feel objects by touching them, but be unable to name them. We may, indeed, be able to see objects or faces, but be unable to recognize them. These difficulties occur even though the person has no problems with their actual senses of sight, hearing or touch.

You can have difficulties in identifying certain sensory impressions if certain parts of your brain are damaged. There are different reasons why parts of the brain might be damaged. One reason, for example, may be a head injury. Damage can also occur if parts of the brain are not properly supplied with blood in the event of a stroke. Parts of the brain can also get damaged if an unusual amount of tissue has grown in the brain. Tissue growths like these can be benign or malignant.