1] Department of Otology and Laryngology, Harvard Medical School, Boston Massachussetts 02114, USA [2] Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston Massachussetts 02114, USA [3] Center for Computational Neuroscience and Neural Technology, Boston University, Boston Massachussetts 02215, USA.
Nat Commun. 2013;4:2547. doi: 10.1038/ncomms3547.
Early binaural experience can recalibrate central auditory circuits that support spatial hearing. However, it is not known how binaural integration matures shortly after hearing onset or whether various developmental stages are differentially impacted by disruptions of normal binaural experience. Here we induce a brief, reversible unilateral conductive hearing loss (CHL) at several experimentally determined milestones in mouse primary auditory cortex (A1) development and characterize its effects ~1 week after normal hearing is restored. We find that CHL shapes A1 binaural selectivity during two early critical periods. CHL before P16 disrupts the normal coregistration of interaural frequency tuning, whereas CHL on P16, but not before or after, disrupts interaural level difference sensitivity contained in long-latency spikes. These data highlight an evolving plasticity in the developing auditory cortex that may relate to the aetiology of amblyaudia, a binaural hearing impairment associated with bouts of otitis media during human infancy.
早期的双耳经验可以重新校准支持空间听觉的中枢听觉回路。然而，目前尚不清楚在听觉出现后不久，双耳整合是如何成熟的，也不知道各种发育阶段是否会因正常双耳经验的中断而受到不同程度的影响。在这里，我们在小鼠初级听觉皮层 (A1) 发育的几个实验确定的里程碑处诱导短暂的、可逆的单侧传导性听力损失 (CHL)，并在正常听力恢复后约 1 周内描述其影响。我们发现 CHL 在两个早期关键期塑造了 A1 的双耳选择性。在 P16 之前发生的 CHL 会破坏两耳频率调谐的正常共定位，而在 P16 时发生的 CHL （而非在此之前或之后）则会破坏长潜伏期尖峰中包含的两耳强度差敏感性。这些数据突出了发育中的听觉皮层中不断发展的可塑性，这可能与 amblyaudia 的病因有关，amblyaudia 是一种与人类婴儿期中耳炎发作相关的双耳听力障碍。
