Paroxysmal dysphasia and the problem of cerebral dominance.

The problem of the functional specialization of the two cerebral hemispheres has its origin in studies of aphasia. In a report which received little attention at the time, Marc Dax maintained (1836) that aphasia was associated with lesions of the left hemisphere. Broca admitted in his earlier writings that both hemispheres might be involved in language functions but in his later observations he insisted that the left hemisphere was dominant for this function. This suggestion was soon confirmed by the observations of Bastian, Hughlings Jackson, and Wernicke. However, exceptions to this rulewere soon noticed. In fact, as from 1865, Broca conceded that there might be a small number of individuals " who were exceptions and would speak with the right hemisphere ", and he approached present-day explanations when he wrote: