Language and aphasias

INTRODUCTION AND OBJECTIVE: Approximately 400,000 years ago men started to use language. Initially it was probably poor with few phonemes. With social evolution it became more complex, with the appearance of new phonemes and a more complete grammatical structure. The current concept of the processing of language dates, with little change, from the nineteenth century. DEVELOPMENT: With the birth of phrenology language began to be studied. This lead to the hypothesis of Wernicke, with two main areas joined by the fasciculo arcuato, which is still held to be valid with modifications by Gerchwind and Damasio, amongst others. Important advances in the study of language are due to Chomsky and his transformational grammar. This supports the universal structure of language, since one learns it following genetically determined laws. Language has three main aspects: creativity which makes both the transmitter and the receiver active participants in communication, the form from which words are constructed and the content of the message. Aphasia is an alteration in the comprehension and understanding of language, which may be the clinical expression of many different aetiologies. They help us to localize the lesion topographically. They are divided depending on the clinical signs, into motor or Broca's aphasia, in which understanding is conserved but the patient uses a language with poor grammatical structure, although the semantic content is acceptable: sensitive or Wernicke's aphasia, with inability to understand and language which is fluid but unintelligible; conduction aphasia due to limitation in the transmission of impulses from Wernicke's area to that of Broca, with acceptable understanding and fluid language and the trans-cortical aphasias where the main characteristic is indemnity of the capacity of repetition. CONCLUSIONS: The aphasias, as the expression of an alteration of language are an important support in the topographical localization of lesions, even before these can be shown on computerized tomography.