Fig. 2.

Nipple movements in the anterior–posterior direction during breast-feeding (data from subject 41). (A) Contours of the tongue (green) and nipple distal surface (purple) after rigid registration around the rigid palate. The black curve represents the average of all contours of the rigid palate. (B) Contours of the palate (red), tongue (green), and nipple (purple) of several frames during a single suckling cycle. The black arrow represents the distance between the nipple tip and the HSPJ (blue circle). (C) The scaled motility of the nipple tip (purple, length of black arrows in B) in comparison with the rigid motility of the anterior tongue (green, average of the motility over lines 1–8 as in Fig. 1D). Nipple movement is provided in Movie S2. HSPJ, hard–soft palate junction.