agraphias

Agraphia is the impaired ability to write due to brain dysfunction. It is typically acquired after stroke, brain injury, or neurodegenerative disease and may occur with aphasia or as an isolated writing disorder. Developmental writing problems are usually described separately as dysgraphia.

Most acquired agraphias result from damage to left-hemisphere language and writing networks, often near the angular gyrus and related language areas. Patients may have intact handwriting motor control but produce misspellings, invented spellings, or disorganized text; in other cases handwriting is illegible or letter formation is affected while language comprehension remains relatively preserved.

Clinically, agraphias are described as central (linguistic) or peripheral (motor). Central forms include phonological agraphia (difficulty spelling nonwords or unfamiliar words), lexical/surface agraphia (difficulty with irregular words, relying on rules), and mixed or deep variants. Peripheral forms include ideomotor or apraxic agraphia (difficulty converting an intended word into the motor action of writing) and graphemic dysgraphia affecting letter sequences.

Diagnosis relies on neuropsychological testing of writing and language, language assessment, and neuroimaging to locate the lesion. Treatment is usually multidisciplinary: speech-language therapy to restore writing or develop compensatory strategies, handwriting practice, adaptation with keyboards or spell-checks, and occupational therapy.

Prognosis varies with age, lesion size and location, and access to rehabilitation. Some individuals recover substantial writing ability, while others retain persistent deficits and rely on adaptive strategies.