If you have experienced any of those “slips” on occasion, then you will have some hint of the types of experience that some people live with constantly. Those people suffer from different types of language disorders, generally described as “aphasia.” Aphasia is defined as an impairment of language function due to localized brain damage that leads to difficulty in understanding and/or producing linguistic forms.

The most common cause of aphasia is a stroke (when a blood vessel in the brain is blocked or bursts), though traumatic head injuries from violence or an accident may have similar effects. Those effects can range from mild to severe reduction in the ability to use language. Someone who is aphasic often has interrelated language disorders, in that difficulties in understanding can lead to difficulties in production, for example. Consequently, the classification of different types of aphasia is usually based on the primary symptoms of someone having difficulties with language.