Historical Aspects Of Aphasia

The cerebral lesions that cause aphasia are generally in the left cerebral hemisphere. Some early Greek medical literature noted speech impairment associated with cerebral damage but little was made of the connection between aphasia and the left cerebral hemisphere until the late 19th century when Paul Broca, a surgeon and anthropologist, reported the autopsy findings of the brains of two patients with aphasia. Twenty-five years before Broca made his observations known, Gustav Dax published a paper written by his father, Marc Dax, in which he presented a mass of evidence supporting the discovery that aphasia was due to lesions of the left hemisphere.

Efforts to localize aphasia in its many forms continued throughout the 19th and 20th centuries by medical scientists such as Wernicke and Lichtheim in Germany, Pierre Marie in France, and Henry Head in Britain. Head took issue with the idea that specific areas of the cortex were responsible for the complex functions necessary for human communication. Among those who contributed to the understanding of aphasia in the early 20th century were Kurt Goldstein, a German neurologist; Weisenburg and McBride in the United States; Alajouanine, Ombre-dane, and Durand in France; and Roman Jakobson, a noted linguist who had emigrated to the United States.

In the early 1960s, Norman Geschwind, a neurologist at the Boston Veteran's Administration Hospital and director of its aphasia center, reinterpreted the works of earlier investigators and stimulated renewed interest in the study of aphasia. His interpretation of aphasia as the result of neural disconnection and concurrent advances in radiologic technology facilitated the neuroanatomical study of aphasia. In this same era, D. Frank Benson (1967) reported findings from one of the first studies that systematically correlated neuroimaging with the symptoms of aphasia. Benson's work provided radiologic confirmation of the distinction between posterior left hemisphere lesions resulting in "fluent" aphasia and posterior lesions with "nonfluent" aphasia using radiologic data. The emergence of such measures as computerized tomography, magnetic resonance imaging, singleemission computed spectography, positron emission tomography, and functional MRI in the last half of the 20th century increased the understanding of the relationships between lesion localization and the signs and symptoms of aphasia. Although the evolution of neuroimaging techniques has had a great impact on the study of the neural basis of aphasia, the autopsy studies that preceded them have withstood the test of time (Fig. 1).

The contemporary study of aphasia has been influenced by the involvement of many disciplines including the late 20th century emergence of speech-language pathology, neuropsychology, behavioral neurology, and neurolinguistics. Each field has brought its particular perspective, expertise, and body of knowledge to bear on the study of aphasia. The founding of the Academy of Aphasia in 1962 and the publication in this period of new journals that address issues bearing on the study of aphasia, such as Cortex,

Brain and Language, and Aphasiology, reflected an increased interest in the condition.

Understanding And Treating Autism

Understanding And Treating Autism

Whenever a doctor informs the parents that their child is suffering with Autism, the first & foremost question that is thrown over him is - How did it happen? How did my child get this disease? Well, there is no definite answer to what are the exact causes of Autism.

Get My Free Ebook

Post a comment