Figure 1. (A) A representative coronal projection of mandibular movement in a subject, which was recorded with the use of a mandibular kinesiograph. The trajectory of the open-close movement in this subject shows a slight deviation to the right at the maximum gape (Aa). When the subject chewed gum without any instruction, the jaw trajectory shows a marked deviation to the left, indicating a strong left chewing-side preference (Ab). When the subject was instructed to chew the gum bilaterally, the laterality of the jaw trajectory disappeared (Ac). Green lines and downward arrows indicate jaw-opening trajectories, while red lines and upward arrows indicate jaw-closing trajectories. Several cycles are superimposed. L indicates the left side. Bars denote 5 mm. (B) Block design of the tongue movement paradigm.