Figure 1

Split motion stimuli are used to decouple eye movements

(A) Schematic of visual stimulation (center). Eye rotations are elicited by rotating radial patterns, split into two hemifields, and projected onto a screen placed below the fish (see Video S1). Both eye and tail positions are tracked during stimulus viewing.

(B) (i) Left and right eye positions are decorrelated when using a split stimulus (left, uncorrelated velocity steps). In comparison, they are highly correlated when using a whole-field rotating grating (right, congruent rotation). (ii) Vergence index for fish presented with split, incongruent motion stimuli (8 fish) and congruent rotation stimuli (5 fish). Filled circles, mean across fish. Open circles, individual fish.

(C) Eye velocity is modulated by stimulus velocity (see also Figure S1). (i) Left eye and right eye velocities (saccades removed) for each stimulus velocity presented on the ipsilateral side of the screen. Red and blue points, mean across fish (N = 8); gray traces, individual fish. The slope of the fitted lines reflects the eye velocity gain, i.e., the modulation of eye velocity by stimulus velocity. (ii) Eye velocity gain, pooled for both eyes, for stimuli grouped into rotating and vergent. Filled circles, mean across fish (n = 8). Open circles, individual fish (see STAR Methods and Figure S1D).

(D) Swimming bout type is modulated by stimulus category (see also Figure S1A). Filled circles, mean across fish (n = 8). Open circles, individual fish. Conv, converging; Div, diverging; LRot, leftward rotation (counterclockwise); RRot, rightward rotation (clockwise).

See also Figure S1 and Video S1.