Figure 4. Visual stimuli used to stimulate the lobula plate network.

a,b To probe the receptive field, a small bar is moved first horizontally to the right at several elevations (a) and subsequently vertically down at several azimuth positions (b). c Virtual environment to create full-field ego-motion stimuli. The walls of the virtual room are projected onto a sphere. d The sphere can be rotated and translated according to the 6 degrees of freedom. e Example snapshots shown in spherical coordinates from image movies obtained for three different kinds of rotations.