University of Groningen, University Medical Center Groningen, Groningen, Department of Otorhinolaryngology and Head/Neck Surgery, 9713, GZ, Groningen, the Netherlands.
Eaton-Peabody Laboratories, Massachusetts Eye & Ear and Department of Otorhinolaryngology and Head/Neck Surgery, Harvard Medical School, Boston, MA, USA.
Hear Res. 2020 Nov;397:107976. doi: 10.1016/j.heares.2020.107976. Epub 2020 Apr 20.
Sensory input has profound effects on neuronal organization and sensory maps in the brain. The mechanisms regulating plasticity of the auditory pathway have been revealed by examining the consequences of altered auditory input during both developmental critical periods-when plasticity facilitates the optimization of neural circuits in concert with the external environment-and in adulthood-when hearing loss is linked to the generation of tinnitus. In this review, we summarize research identifying the molecular, cellular, and circuit-level mechanisms regulating neuronal organization and tonotopic map plasticity during developmental critical periods and in adulthood. These mechanisms are shared in both the juvenile and adult brain and along the length of the auditory pathway, where they serve to regulate disinhibitory networks, synaptic structure and function, as well as structural barriers to plasticity. Regulation of plasticity also involves both neuromodulatory circuits, which link plasticity with learning and attention, as well as ascending and descending auditory circuits, which link the auditory cortex and lower structures. Further work identifying the interplay of molecular and cellular mechanisms associating hearing loss-induced plasticity with tinnitus will continue to advance our understanding of this disorder and lead to new approaches to its treatment.
感觉输入对大脑中的神经元组织和感觉图谱有深远的影响。通过研究在发育关键期（即可塑性促进神经网络与外部环境协同优化的时期）和成年期（即听力损失与耳鸣产生相关的时期）改变听觉输入的后果，已经揭示了调节听觉通路可塑性的机制。在这篇综述中，我们总结了研究确定分子、细胞和电路水平机制的研究，这些机制调节了发育关键期和成年期的神经元组织和音位图可塑性。这些机制在幼年和成年大脑以及听觉通路上都是共享的，它们用于调节去抑制网络、突触结构和功能，以及可塑性的结构障碍。可塑性的调节还涉及到神经调节回路，这些回路将可塑性与学习和注意力联系起来，以及上行和下行听觉回路，这些回路将听觉皮层和较低的结构联系起来。进一步研究确定与听力损失引起的可塑性相关的分子和细胞机制与耳鸣之间的相互作用，将继续推进我们对这种疾病的理解，并为其治疗带来新的方法。
