Friday, October 28, 2011
Hall 1-2 (San Jose Convention Center)
In order to better understand the changes that affect the human mind as it ages, it is worthwhile to study these changes in simpler animals. Both vertebrates and invertebrates are able to produce new neurons in specific brain regions during adulthood. In the common house cricket adult neurogenesis has been found to occur in the mushroom bodies, a sensory integrative area of the brain associated with memory and learning that is considered to be analogous to the mammalian hippocampus. Hormonal and sensory control of neurogenesis has been closely examined in adult crickets, but not much is known about how neurogenesis might change over their lifespan. The current experiment is examining whether or not the rate of neurogenesis differs between juvenile and adult crickets. By injecting crickets with a thymidine analogue, 5-bromo, 2’-deoxyuridine that is incorporated into cells during mitosis, and then performing immunohistochemistry on the dissected cricket brains, we are able count proliferating cells in the mushroom bodies. We expect to find a greater number of proliferating cells in the brains of juvenile crickets compared to adult crickets. If our hypothesis proves to be correct, we will conduct further studies to determine how the developmental stage of the animals, their sex and the environment (external and internal) might contribute to enhancing or inhibiting neurogenesis. In addition, it is of great interest to learn more about the specific functions of neurogenesis and to see if these functions differ over the lifespan of an animal.