This research project is dedicated to answering three basic questions about the development of the visual system: 1) how do nerve cells connect to each other; 2) how do nerve cells know where to connect to each other and 3) how does nerve cell activity influence the connections? The answers can be found by studying the prenatal and postnatal development of the cat visual system, which is remarkably similar to that in the human. During development the connections nerve cells make are not the same as those found in the adult. It is important, therefore, to ascertain what determines which connections are eliminated or preserved. Although it is known that activity influences which connections nerve cells make, it is not clear how it is done. This project will study the anatomy and physiology of developing nerve cells and whether certain types of "growth-associated proteins" (GAP) regulate this process. Abnormal nerve cell activity during development may lead to birth defects. The use of certain drugs which cross from mother to fetus may have this effect. Toxic substances could also affect the proper development of the visual system after birth by abnormally stimulating or inhibiting nerve cell activity. Studying the processes regulating normal development can further our understanding of defects of the visual system.
