Figure 2. Examples of responses from single masseter muscle spindle units to ramp-and-hold stretch. (A) Typical responses from (a) Control group, (b) two-week iOVD group, and (c) eight-week iOVD group. (B) Ramp-and-hold stretch was applied with maximum opening distance of 7.0 mm; stimulus duration was 8.5 sec, divided into 4.5 sec and 4.0 sec for ramp-stretch and hold phases, respectively.