Behavioral analysis of Drosophila landmark learning in the flight simulator.

Drosophila flies can be trained in the flight simulator to operantly avoid heat by choosing certain orientations relative to landmarks. Flies primarily store pattern orientations associated with the absence of heat. They readily escape from heat-associated orientations under the direct influence of the reinforcer but not in the subsequent memory tests. The flies tend to keep the largest possible distance from the "hot" or potentially "hot" regions, that is, they head toward the center of the "cold" sector. The results are discussed in the light of the retinotopic matching model explaining visual memory in flies by the superposition of a retinotopically stored template with the actual retinal image. Window experiments confining visual feedback to two 90 degrees sectors indicate that the memory template covers most of the visible space.