Aphasia is an inability to comprehend or formulate language because of damage to specific brain regions. The major causes are stroke and head trauma; prevalence is hard to determine but aphasia due to stroke is estimated to be 0.1–0.4% in the Global North. Aphasia can also be the result of brain tumors, brain infections, or neurodegenerative diseases (such as dementias). To be diagnosed with aphasia, a person's speech or language must be significantly impaired in one (or more) of the four aspects of communication following acquired brain injury. Alternatively, in the case of progressive aphasia, it must have significantly declined over a short period of time. The four aspects of communication are auditory comprehension, verbal expression, reading and writing, and functional communication. The difficulties of people with aphasia can range from occasional trouble finding words, to losing the ability to speak, read, or write; intelligence, however, is unaffected. Expressive language and receptive language can both be affected as well. Aphasia also affects visual language such as sign language. In contrast, the use of formulaic expressions in everyday communication is often preserved. For example, while a person with aphasia, particularly expressive aphasia (Broca's aphasia), may not be able to ask a loved one when their birthday is, they may still be able to sing "Happy Birthday". One prevalent deficit in the aphasias is anomia, which is a difficulty in finding the correct word. With aphasia, one or more modes of communication in the brain have been damaged and are therefore functioning incorrectly. Aphasia is not caused by damage to the brain that results in motor or sensory deficits, which produces abnormal speech; that is, aphasia is not related to the mechanics of speech but rather the individual's language cognition (although a person can have both problems, particularly if they suffered a hemorrhage that damaged a large area of the brain). An individual's "language" is the socially shared set of rules, as well as the thought processes that go behind verbalized speech. It is not a result of a more peripheral motor or sensory difficulty, such as paralysis affecting the speech muscles or a general hearing impairment. Prevalance Aphasia affects about two million people in the U.S. and 250,000 people in Great Britain. Nearly 180,000 people acquire the disorder every year in the U.S., 170,000 due to stroke. Any person of any age can develop aphasia, given that it is often caused by a traumatic injury. However, people who are middle aged and older are the most likely to acquire aphasia, as the other etiologies are more likely at older ages. For example, approximately 75% of all strokes occur in individuals over the age of 65. Strokes account for most documented cases of aphasia: 25% to 40% of people who survive a stroke develop aphasia as a result of damage to the language-processing regions of the brain.
symptom of Vertebral artery dissection
symptoms of Vertebral artery dissection
symptom of Intracranial aneurysm
symptom of Intracerebral hemorrhage
medical cause of Vertebral artery dissection
symptom of Subarachnoid hemorrhage
symptom of Meningioma
symptom of Brain tumor