The term middle temporal sulcus refers to the central of three short sulci on the ventrolateral surface of the temporal lobe of the macaque. It is identified by gross observation. The other two are the posterior middle temporal sulcus and the anterior middle temporal sulcus ( Bonin-1947 ). The three represent an interrupted sulcus that contributes to the boundary between the middle temporal gyrus and the inferior temporal gyrus. The middle sulcus is topologically equivalent to the central part of the inferior temporal sulcus of the Human ( Ono-1990 ). It is not found in the rat or mouse ( NeuroNames ). The fact that most brain atlases of the macaque ( Martin-2000; Paxinos-2009a ) and the Human ( Ono-1990; Duvernoy-1992; Mai-1997 ) continue to refer to the interrupted sulcus in this location by different names is a source of some confusion in primate cortical anatomy. The root of the confusion appears to be that anatomists who worked with either species in the mid-1900s and who used the term 'middle temporal sulcus' referred to the occipitotemporal sulcus as 'inferior temporal sulcus' ( Crosby-1962; Roberts-1970 ). Since the late 1900s anatomists working with both species have settled on ' occipitotemporal sulcus ' for the more ventral sulcus ( Ono-1990; Martin-2000 ). Human atlases have settled on inferior temporal sulcus for the sulcus marking the lower boundary of the middle temporal gyrus ( Ono-1990 ), but macaque atlases continue to refer to it as a two- or three-part middle temporal sulcus ( Martin-2000; Paxinos-2009a ).