CORTICAL ORGANIZATION OF LANGUAGE FUNCTIONS

In accord with Pavlovian terminology, the human cortex comprises the "superior ends" of four major analyzers: (1) the visual analyzer, (2) the auditory analyzer (3) the somesthetic/kinesthetic analyzer and (4) the motor analyzer. Each analyzer is represented by a primary area bordered by secondary and tertiary areas or "areas of overlap" with other analyzers. Although Luria summarized the sites of lesions in terms of the Brodmann and Vogts classifications, he usually used the less specific designations: "frontal," "parietal," "occipital," and "temporal" as corresponding roughly to "motor," "somesthetic-kinesthetic," "visual," and "auditory" analyzers respectively. He concluded that the most important areas in aphasia were not the primary projection areas but the secondary and tertiary areas of overlap between the analyzers.

Luria recognized four major categories of aphasia:

Auditory Aphasias associated with lesions of the temporal lobe

Afferent Motor Aphasias associated with lesions of the anterior portion of the parietal lobe

Efferent Motor Aphasias associated with lesions of the premotor areas of the frontal lobe

Semantic Aphasias associated with lesions of the parieto-temporo-occipital area

In addition, he described several more specific syndromes, such as (Frontal) Dynamic Aphasia, (Temporal) Auditory-Mnestic Aphasia, and Premotor Speech Disturbances, which are not covered in this summary.