Figure 1. Experimental design.

(A, B): Tethered crickets were walking on a trackball while male calling song was presented from different angles of incidence between 0° and ±30°. Speaker position and acoustic stimulation was computer controlled. The rotations of the trackball were monitored and provided the walking velocity and the steering velocity of the animal. The steering velocity was integrated to calculate the lateral deviation in response to acoustic stimulation. (B, C): Laservibrometric and neurophysiological recordings. Crickets were tethered into a wireframe and placed on a trackball in walking posture. Traces show sound pulses presented from 30° ipsilateral and contralateral, sound level recordings above the cricket, tympanic membrane oscillations and the auditory afferent responses. The afferent activity was full wave rectified and 100 responses were averaged.