SENSORY REGULATION OF ADULT NEUROGENESIS

双侧耳蜗切除改变了成年鸟类鸣唱系统中鸣唱行为相关区域的神经元周转。拟议研究的目标是：1）确定受耳蜗移除影响的神经元周转过程; 2）确定这些细胞效应是否是由于感觉剥夺，特别是缺乏与歌曲相关的听觉刺激。耳聋可以延长神经元的存活。通过改变耳聋和细胞出生的时间，我们将评估耳聋对新神经元存活的影响。在形成后的最初几周内，耳聋也可能减少细胞增殖或减少神经元存活。拟议中的实验将区分这两种假设。在一个区域中发现了经历替换的神经元，该区域响应于与歌曲相关的听觉刺激而增加尖峰活动。通过阻断听觉鸟类与歌唱相关的听觉刺激，我们将确定与歌唱相关的听觉剥夺是否是双侧耳蜗摘除的原因。由于神经元活动与复杂的、习得的、发声行为紧密相连，因此听觉体验、细胞更新和行为之间的关系可以在这个系统中得到很好的表征。本研究的目的是确定调节神经元替代的正常感觉要求。深入了解成人神经发生、合并和细胞死亡的调节机制，有望有助于我们理解神经回路的维持、修饰和修复的基本规则。这项研究最终可能被证明对设计修复成人大脑的策略有用。

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.