Neural basis of odor-source searching behavior in insect brain systems evaluated with a mobile robot.

More than 3 million species of insects live around the world in a variety of environments, and display a diversity of sophisticated behaviors adapted to these environments. Our research is aimed at understanding how the brain systems of insects process constantly changing environmental information and generate adaptive behaviors. Specifically, we are investigating how odor information is processed and modified by other sensory modalities and experience (i.e. learning and memory). It is well known that males of many moth species can detect their species-specific pheromones at low concentrations and orient successfully toward the odor source (e.g. females) even though the odor-source is far away. This may depend not only on high sensitivity to olfactory information by insect olfactory receptors, but also on superior behavioral strategies or algorithms based on processing by neural networks in the insect brain (Arbas et al., 1993; Kanzaki, 1998). Insects have become an excellent model for understanding adaptive control in biological systems which has inspired research and development of control and communication in engineered systems. It is our long-term goal to understand the behavioral and neural basis of behavior of insects. To this end we have investigated the algorithms used to search for and locate a pheromone source and its underlying control mechanisms in the brain of the male silk moth, Bombyx mori. To evaluate the behavioral model we have implemented it in an insect-size mobile robot as a controller for the robot behavior.