3rd instar larvae: 406 (n=2)

Adult: 1430 (n=2) (VNC excluded)

The previous cell count was done considering only the central brain. Here I included the VNC in order to have a more complete information

Unfortunately it looks like it is impossible for me to recognize cell bodies. I can only see neuropil, therefore I can not look for colocalizations.

The optomotor stimulus consists of a striped arena with panoramic vertical stripes rotating horizontally around the vertical, or yaw axis. Depending on the spatial wavelenght (or spatial frequency, SF) the fly’s optomotor response (OR) is changing supposedly to reach a maximum between 20-40°
(with a pattern motion of 0° ) . As the panoramic stripes are rotating a tethered fly will actively steer in the direction of the motion. After its maximum the OR gradually decreases with an increasing spatial frequency to finally reach 0 around 9.6-6.3°. A tendency to negative/reversed OR has been observed as the SF reaches 6.3°.

This experiment has been shown before in 1976 by E. Buchner, Elementary movement detectors in an insect visual system. Bioi Cybern 24:85- 101, Figure 8 page 93. Attaching Figure 8 as a reference.