Fig. 3.

Normalized first dorsal interosseus EMG power across four different frequency bands (5–13, 13–30, 30–60, and 60–100 Hz), three different visual angles (0.05, 0.5, and 1.5°), and two force levels (2% and 30% MVC). It is evident that visual angle influenced EMG power only from 13 to 30 Hz. This finding was consistent for young and older adults at both force levels. In addition, there were some age-associated differences as a function of frequency band. Specifically, at 2% MVC, older adults exhibited greater normalized power from 5 to 13 Hz at the lowest visual angle, whereas at 30% MVC, young adults exhibited greater normalized power from 5 to 13 Hz at the lowest visual angle. Also, at 30% MVC, older adults exhibited greater normalized power from 13 to 30 Hz at the lowest visual angle. Asterisk above the symbols indicate age differences, while asterisk above the line indicate visual angle differences