Figure 1.

Schematic diagram of recording chamber. (A) Overview of the recording chamber. The grey screen is made of a back-projector screen, which presents the stimulus to the eye while the animal is in the chamber. Tadpole is secured on a sylgard cushion with insect pins and stuck to the rotatable bar with grease. Adjust the angle of the bar and face the retina vertical to the back-projector screen. The white square represents one stimulus grid on the black background. (B) Front view of the recording chamber. Place a convex lens in front of the projector to control the projected image size. Remove the condenser before placing the chamber to the stage.