Comparative anatomy of the macaque and the human frontal oculomotor domain.

• In macaques, the frontal eye field (FEF) plays a crucial role in oculomotor control and spatial attention. • In humans, oculomotor and spatial attention tasks activate two frontal sectors (dorsal and ventral hFEF). • The definition of the possible macaque homologs of the two hFEFs is still matter of debate. • In macaques the FEF is surrounded rostrally by several distinct eye-related areas, including areas 45B, and 45A. • It is suggested a homology of the dorsal and ventral hFEF with the macaque FEF and area 45B, respectively. In non-human primates, at the junction of the prefrontal with the premotor cortex, there is a sector designated as frontal eye field (FEF), involved in controlling oculomotor behavior and spatial attention. Evidence for at least two FEFs in humans is at the basis of the still open issue of the possible homologies between the macaque and the human frontal oculomotor system. In this review article we address this issue suggesting a new view solidly grounded on evidence from the last decade showing that, in macaques, the FEF is at the core of an oculomotor domain in which several distinct areas, including areas 45A and 45B, provide the substrate for parallel processing of different aspects of oculomotor behavior. Based on comparative considerations, we will propose a correspondence between some of the macaque and the human oculomotor fields, thus suggesting sharing of neural substrate for oculomotor control, gaze processing, and orienting attention in space. Accordingly, this article could contribute to settle some aspects of the so-called "enigma" of the human FEF anatomy. [ABSTRACT FROM AUTHOR]