MOTOR CORTEX FIELDS AND SPEECH MOVEMENTS - SIMPLE DUAL CONTROL IS IMPLAUSIBLE (CORRECETED VERSION OF 126BQ)

We applaud the spirit of MacNeilage's attempts to better ex plain the evolution and cortical control of speech by drawing on the vast litera ture in nonhuman primate neurobiology. However, he oversimplifies moto r cortical fields and their known individual functions to such an exte nt that he undermines the value of his effort. In particular, MacNeila ge has lumped together the functional characteristics across multiple mesial and lateral motor cortex fields, inadvertantly creating two hyp othetical centers that simply may not exist.