THE LEFT TEMPORAL POLE IS IMPORTANT FOR RETRIEVING WORDS FOR UNIQUE CONCRETE ENTITIES.

BACKGROUND

The neuroanatomical basis of lexical retrieval has been studied intensively. The current review focuses on the special case of proper nouns.

AIMS

This article reviews a program of research that has used both lesion-deficit and functional imaging (PET) approaches to investigate the neuroanatomical basis for lexical retrieval of proper nouns. In lesion-deficit studies, we found that damage to the left temporal polar (TP) region leads to reliable and specific impairments in naming famous persons (e.g., "George Clooney") and famous landmarks (e.g., "Golden Gate Bridge"). In functional imaging studies, we found that when participants name famous persons and landmarks, they produce specific activation (increases in regional cerebral blood flow) in the left TP region.

MAIN CONTRIBUTION

These findings converge with lesion and functional imaging data from other laboratories to support the idea that the left TP region is important for the retrieval of names for unique concrete entities, persons and landmarks being typical examples of such categories of entities.

CONCLUSIONS

We have interpreted these results within a theoretical framework that suggests that left TP contains convergence regions that operate as intermediaries between conceptual knowledge retrieval and lexical retrieval for classes of unique concrete entities.