Fig. 3. The magnitude of the wingbeat responses to concurrent oscillations about the pitch (A) and roll (B) axes is a function of the phase offset between mechanical and visual stimuli. (A) Pitch axis responses (mean ± S.E.M., N=10 flies). (B) Roll axis responses (mean ± S.E.M., N=14 flies). The amplitude of the sine fits to wingbeat data (R_m+v; green circles) are plotted against phase offset (). In addition, two possible fits for the data are plotted: linear summation (R_m+R_v; black curve) and scaled summation (R_m+ßR_v; red curve). The two fitted functions are 4th order polynomials.