SENSORY REGULATION OF ADULT NEUROGENESIS

双侧耳蜗切除改变了成年鸟类鸣叫系统中潜在鸣叫行为区域的神经元转换。本研究的目标是1)确定受耳蜗切除影响的神经元转换过程，2)确定这些细胞效应是否由于感觉剥夺，特别是缺乏与歌曲相关的听觉刺激。震耳欲聋可能延长神经元的存活时间。通过改变耳聋的时间和细胞出生日期，我们将评估耳聋对新神经元存活的影响。耳聋也可能在形成后的最初几周内减少细胞增殖或减少神经元存活。拟议的实验将区分这两种假设。接受替换的神经元位于一个区域，该区域在对与歌曲相关的听觉刺激做出反应时，会增加尖峰活动。通过阻断听觉鸟类与歌声相关的听觉刺激，我们将确定与歌声相关的听觉剥夺是否对双侧耳蜗切除的影响负责。由于神经元活动与复杂的、习得的、歌曲产生的行为紧密相连，听觉体验、细胞更新和行为之间的关系可以在这个系统中很好地表征。本研究的目的是确定调节神经元替代的正常感觉需求。对调节成人神经发生、合并和细胞死亡的机制的深入了解，可能有助于我们理解控制神经回路维持、修改和修复的基本规则。这项研究可能最终被证明有助于设计修复成人大脑的策略。

Bilateral cochlea removal alters neuronal turnover in the adult avian song system in regions underlying singing behaviors. The goals of the proposed research are 1) to identify the processes of neuronal turnover that are affected by cochlea removal and 2) to determine whether these cellular effects are due to sensory deprivation, specifically the absence of song-related auditory stimulation. Deafening may prolong neuron survival. By altering the timing of deafening and cell birthdating, we will evaluate the effects of deafening on new neuron survival. Deafening may also either decrease cell proliferation or decrease neuron survival during the first few weeks after formation. The proposed experiments will discern between these two hypotheses. Neurons that undergo replacement are found in a region that increases spiking activity in response to song-related auditory stimulation. By blocking song-related auditory stimulation in hearing birds we will determine whether song- related auditory deprivation is responsible for the effects of bilateral cochlear removal. Because neuronal activity is tightly linked to the complex, learned, behavior of song production, the relationship between auditory experience, cell turnover, and behavior can be well characterized in this system. The goal of this research is to identify the normal sensory requirements for regulating neuronal replacement. Insight into mechanisms regulating adult neurogenesis, incorporation, and cell death may be expected to contribute to our understanding of the basic rules governing the maintenance, modification, and perhaps repair of neural circuits. This research may ultimately prove useful in designing strategies to repair the adult human brain.