Neurobiology of Mammalian Photoperiodism

光影响生理和行为的日常(昼夜节律)和季节周期。努涅斯博士将研究神经和内分泌系统，这些系统调节光对这些生物节律的影响。下丘脑的视交叉上核被认为是生物钟的神经底物。因此，努涅斯博士将专注于识别核团的输出，以确定昼夜节律信号如何到达中枢神经系统的其他部分。昼夜节律系统和视交叉上核都参与了季节性生殖周期的产生，但参与季节性周期的这一神经结构的投射或输出似乎与负责每日周期的投射不同。似乎季节性周期也可能牵涉到下丘脑室旁核。努涅斯博士还将研究起源于这种大脑结构的途径。此外，他还将阐明取消季节性周期性的神经损伤所产生的内分泌变化。有关这一生物钟的解剖学和生理学的信息为更全面地了解某些极端的精神障碍以及情绪和生产力在更正常范围内的波动提供了基础科学。光周期控制知识的另一个价值可能在于提高畜牧业的效率。

Light affects daily (circadian) and seasonal cycles in physiology and behavior. Dr. Nunez will examine the neural and endocrine systems that mediate these effects of light on these biological rhythms. The suprachiasmatic nucleus of the hypothalamus is believed to be the neural substrate for the biological clock. Therefore, Dr. Nunez will concentrate on identifying the outputs of the nucleus to determine how circadian signals reach the rest of the central nervous system. Both the circadian system and the suprachiasmatic nucleus are involved in the generation of seasonal reproductive cycles but the projection or output from this neural structure involved in seasonal cycles appears to be different than the projections responsible for daily cycles. It appears that seasonal cycles may also involve the paraventricular nucleus of the hypothalamus. Dr. Nunez will also investigate the pathways that originate in this brain structure. In addition, he will elucidate the endocrine changes that are produced by neural damage that abolishes seasonal cyclicity. Information about the anatomy and physiology of this biological clock provides the basic science for a more comprehensive understanding of certain psychiatric disorders at the extreme and fluctuations in mood and productivity in the more normal range. An additional value of knowledge of controls of photoperiodism may lie in an increased efficiency in animal husbandry.