Fig.
3: The two spherical coordinates psi and theta of a fly's visual space
and its three degrees of freedom for rotation (yaw, roll, pitch; redrawn
from Heisenberg and Wolf, 1984).In the flight simulator a single tethered Drosophila fruitfly flies stationarily in an artificial environment. Originally, open loop experiments, in which the fly's behavior has no effect upon its visual stimulus situation, were utilized for detailed examination of Drosophila's optomotor behavior (e.g. Heisenberg and Wolf, 1984; Heisenberg and Wolf, 1993). In this setup, however, the fly can be enabled to control some aspects of its visual input by coupling it to its motor-output (closed loop). Both the visual input and the motor-output are monitored on-line throughout the experiment.
Such a flight simulator setup is ideally suited for a detailed comparison of classical and operant conditioning, since various contingencies among behavioral output, visual input and the reinforcer - everything in exquisite control of the experimenter - can be established. In the present study, the environment consists of a cylindrical panorama arranged to center the fly within the cylinder. The motion of the environment is limited to the horizontal plane: only the rotational speed of the cylinder can be controlled by the fly's tendency to turn around its vertical body axis (yaw torque, see Fig. 3).
Fig.
3: The two spherical coordinates psi and theta of a fly's visual space
and its three degrees of freedom for rotation (yaw, roll, pitch; redrawn
from Heisenberg and Wolf, 1984).