This paper explores previous studies on the dorsal system of the human brain, which is related to a variety of cognitive functions. It aims to support that the human brain is composed of numerous dorsal pathways. In order to account for this view, the authors use the method of “in vivo probabilistic tactography”. The results have shown that there is a dissociation between two pathways of the human brain: i) inner/ventro-dorsal arc of fibres (responsible for the acoustic-motor speech interface) and ii) outer-dorsal arc (responsible for object use and cognitive control interface). The core contribution of this study is that i) the left part of the human brain exhibits a higher functional complexity than the right one in terms of cognitive skills and ii) there are connective pathways for auditory-oral motor functions and for visual-semantic hand motor functions.