Aphasia I: Clinical and Anatomic Issues

The clinical study of aphasia began in 1861 with the observations of Paul Broca. Within 40 or 50 years, all of the basic clinical phenomena reviewed here had been described and many of the major flashpoints of clinical and theoretical disagreement had been identified. In the past 20 years, fresh interest has come to clinical aphasia research from two directions: modern neuroimaging and cognitive neurosciences. Together, they have additionally provided tools to carry out aphasia-related language experiments in normals. Furthermore, old questions such as cerebral laterality, the influence of handedness, the effects of gender and bilingualism on aphasia, and the mechanisms of recovery have been reexplored. Much of this chapter—which reviews the basic clinical features of aphasia—could have been written 20, 50, or even 100 years ago. In 1995, it is possible to consider this material with greater appreciation of the variability found in the basic syndromes, of their anatomic complexities, of the natural history of recovery, and (although here only briefly) of the cognitive and linguistic deficits that fundamentally underlie the classic syndromes. The chapters on neuroimaging and on cognitive analysis of aphasia should be read along with this chapter.