Dr. Nicholas Strausfeld is an extremely gifted scientist who has been gathering a volume of information on the organization of the insect brain. His previous work has focused on the neuroanatomy and functional organization of the brain and thoracic nervous system of dipterous insects, in particular the blowfly. In his new research program he shall exploit a cardinal feature of arthropod brains: namely, the presence of a manageable number of large nerve cells with characteristic forms, which are readily identifiable in all individuals of a species and which can be unambiguously related to specific motor neuron pools innervating identified muscles used in a specified locomotor function. The ultimate goal of this new line of research is to resolve the functional organization of neurons that mediate polarized-light orientation. To this end the project is restricted to the analysis of clearly defined and neuroanatomically identifiable sensory systems leading to identified motor neurons and muscles. The physiological studies are specifically designed to test the activities of premotor descending neurons in response to polarized light in the context of other visual and mechanical cues, such as would normally be encountered. The research will test current hypotheses concerning polarized-light-sensitive networks. This work is important because it seeks to functionally detail a complete neuronal circuit from sensory input to muscle movement, a circuit in which the anatomy of the neurons has already been beautifully described.
