Figure 4.

Quantification of eye and tail responses. (A) Eye vergence angle before and after convergence responses to leftward (green) and rightward (yellow) moving stimuli. Thick gray bar shows mean vergence angles which are also depicted in the schematics. (B) Change in eye position during eye convergence plotted against initial eye position for the left (blue) and right (red) eyes for trials with leftward (top) and rightward (bottom) moving spots. (C) Initial eye position, before visual stimulus presentation, for trials in which the fish responded to the stimulus versus trials in which there was no response. Data shown as mean ± s.e.m. and mean eye positions are depicted in schematics below the plots. (D) Mean cumulative angle of the tail measured in a 1.2 s time window surrounding spontaneous and stimulus-evoked eye convergence responses. Circles indicate average values across all responses (mean ± s.e.m.). (E) Tail responses associated with eye convergence for leftward (green) and rightward (yellow) moving spot trials. Total cumulative tail angle is plotted against time and traces are aligned to the peak of the first tail bend, indicated by the vertical gray line. Two examples have been colored dark gray to highlight the multiple unilateral tail bends (indicated by small circles), which characterize the responses. (F) Cumulative tail angle along the length of the tail (anterior → posterior) at the peak of the first J-bend (time marked by vertical gray line in (E)). Thick lines with symbols show mean profiles. (G) Schematics showing model tails reconstructed from the mean tail angle profiles in (F). The eyes are shown at the mean vergence angle following the eye convergence response.