Krifka (The origin of topic/comment structure, of predication, and of focusation in asymmetric bimanual coordination, 2006, Interdisciplinary Studies on Information Structure (ISIS): Working Papers of SFB 632 08: 61–96, 2007b) suggests that asymmetric bimanual coordination and ultimately the evolution of lateralization in humans may be the cognitive basis of linguistic topic-comment structure and foreground-background structures in general. As asymmetric bimanual constructions abound in sign languages and are also found in their possible precursors, cospeech gesture and homesign, sign languages may serve (...) as a test ground for the hypothesis. Asymmetric bimanual constructions are indeed used for differentiating foreground and background in sign languages, but some of these constructions are derived from indexical gestures, not manipulation, i.e., they draw on visual attention. Signed topics may be marked by nonmanual features derived from signals of visual attention, and the defining feature of signed topics is eye contact with the addressee, needed to establish a communicative common ground. There, thus, seems to be not one embodied origin of topic-comment structures, but several. Finally, signed topic-comment structure demonstrates how attention shifts in the course of the entire structure, thereby explaining how topics can be described alternately as foreground (e.g., Talmy, Attention phenomena, Oxford University Press, 2007: 265) and background (Jacobs, Linguistics 39: 641–681, 2001). (shrink)