The olfactory coding mechanism responsible for reproductive behaviour have been thoroughly investigated in heliothine moths. This sub-family is particularly fascinating since the individuals communicate both within and across the species. Thus, the males possess receptor neurons detecting pheromones leading to attraction as well as receptor neurons detecting interspecific signals leading to avoidance. In the project presented here we intend to understand the relationship between connectivity patterns and olfactory-mediated behaviours by exploring the neural pathways from defined male specific glomeruli of the antennal lobe to higher integration centres in the brain of Helicoverpa assulta. The methods involve intracellular recordings from antennal-lobe pro jection neurons combined with fluorescent stainings for morphological characterization. By use of confocal microscopy and advanced visualization software the stained neurons will be reconstructed. By performing double labeling experiments, the projection patterns of physiologically/morphologically identified antennal lobe neurons will be compared with the the distribution patterns of relevant neuroactive substances.