Information about diverse environmental factors, such as day length (i.e., season), time of day, temperature, availability of food and/or water, presence of conspecifics that may be either competitors for limited resources (e.g. food) or potential mates, is processed and integrated by the central nervous system. Utilizing both this environmental input and information about the individual's internal status (e.g. nutritional, sexual maturity), the brain sets in motion a variety of coordinated adaptive responses that involve the neuroendocrine system. The goal of Dr. Ball's research is to examine the neuroendocrine integration of environmental information regulating reproduction. He has selected a species that show dramatic changes over the course of a year in their propensity to exhibit an endocrine response to photoperiodic stimuli that regulate the timing of reproduction. Dr. Ball proposes that the neuropeptide gonadotrophin-releasing hormone (GnRH) is involved in the integration of signals. He will determine whether GnRH changes in specific brain structures in response to seasonal variation. Moreover, he will examine how extra-photoperiodic stimuli and physiological conditions affect reproductive activity as measured by plasma hormone levels, gonadal growth as well as GnRH neurochemistry. These studies should provide new insight into both how the central nervous system assimilates the varied stimuli that regulate reproduction and the nature of seasonal plasticity in the neurochemical systems involved in mediating variation in responses to stimuli. Understanding the brain's integration with physiological and behavioral systems can lead to the elucidation of basic principles that underlie the conservation and restoration of biological diversity. Moreover, it could provide a more thorough understanding of how species adapt to adverse environmental changes that may prove important to human adaptation in this changing world.
