Figure 2.

Experimental design for the flight room experiments and the two different behavioral paradigms used for chronic recordings. A, Top view of the flight room, showing position of high-speed cameras (240 frames/s). Bats are permitted to fly within the entire room, but the edible target is only hung within the target area. B, During virtual target amplitude discrimination trial sonar calls produced by a bat are acquired, modified to simulate sonar echoes, and played back to the bat. Playback echoes are either from a loud intensity group (I) or a soft intensity group (II). The delays of the playback echoes are randomly chosen during the trial from a limited range of values (7–12 ms). C, Schematic of the virtual target amplitude discrimination setup. Bats rest on a behavioral platform and produce sonar vocalizations directed toward an ultrasonic microphone. The signals are modified by a computer and played back to the bat via a speaker positioned above and behind the microphone. D, Schematic of the real oscillating target tracking setup. Bats are trained to rest on a platform and use echolocation to track and capture a moving target. The target, positioned on a horizontal arm connected to a single pivot point vertical pendulum, swings in a single plane intersecting the bat's position.