Progressive nonfluent aphasia

Progressive nonfluent aphasia is a form of primary progressive aphasia characterized by apraxia of speech and deficits in processing complex syntax. It is similar to Broca's aphasia and is associated with left inferior frontal and insular atrophy.

Progressive nonfluent aphasia is one of three clinical syndromes associated with frontotemporal lobar degeneration. Thus, some cases are thought to be caused by either Pick's disease or dementia lacking distinctive histology. However, many cases may have neither of these types of pathology and are thought to result instead from corticobasal degeneration.