Neural Control Systems Underlying Insect Feeding Behavior

The blowfly, Phormia regina, provides a model System for the study of neural control systems underlying the regulation of insect feeding behavior This animal regulates its daily food intake. The external chemoreceptors which drive feeding are well characterized and two sets of internal receptor which supply negative feedback to feeding behavior have recently been described. Both sets of internal receptors are stretch receptors activated by gut movements, hence there is no direct monitor for calorie value in the system. The properties of interneurons which integrate internal and external sensory input and command proboscis extension motoneurons must be inferred from behavioral data, however the wealth of behavioral data available suggests scveral interesting classes of interneuronal circuits, including some with a limited amount of plasticity. The neural machinery controlling feeding can be viewed as one component of the mechanism for metabolic homeostisis.