Assaying Visual Memory in the Desert Locust.

The involvement of associative learning cues has been demonstrated in several stages of feeding and food selection. Short neuropeptide F (sNPF)， an insect neuropeptide whose effects on feeding behavior have previously been well established， may be one of the factors bridging feeding and learning behavior. Recently， it was shown in Drosophila melanogaster that the targeted reduction of Drome-sNPF transcript levels significantly reduced sugar-rewarded olfactory memory. While Drosophila mainly relies on olfactory perception in its food searching behavior， locust foraging behavior is likely to be more visually orientated. Furthermore， a feeding-dependent regulation of Schgr-sNPF transcript levels has previously been observed in the optic lobes of the locust brain， suggesting a possible involvement in visual perception of food and visual associative memory in this insect species. In this study， we describe the development of a robust and reproducible assay allowing visual associative memory to be studied in the desert locust， Schistocerca gregaria. Furthermore， we performed an exploratory series of experiments， studying the role of Schgr-sNPF in this complex process.