Development of spectral and temporal response selectivity in the auditory cortex
Development of spectral and temporal response selectivity in the auditory cortex
复制标题
DOI：
10.1073/pnas.0508239102
复制
发表时间：
2005-11-08
影响因子：
11.1
通讯作者：
Merzenich, MM
中科院分区：
文献类型：
--
作者：
Chang, EF;Bao, SW;Merzenich, MM
听力选择性在早期发育过程中被细化和完善的机制还不完全确定。在这项研究中，我们记录了逐渐成熟的抑制影响对初级听觉皮层频谱和时间反应特性的改进的贡献。幼龄大鼠听觉皮层神经元的抑制性感受野（IRFs）比成年大鼠的频谱宽得多，持续时间长得多。相对于兴奋性感受野的选择性细化，irf的选择性细化延迟了大约2周的时间，这与可塑性的关键期相对应。局部应用GABA(a)受体拮抗剂表明，皮质内抑制有助于这种频率选择性反应的渐进式感受野成熟。相反，它对irf的持续时间或连续信号皮层反应恢复时间没有影响。当在连续中等强度噪声环境中饲养的大鼠幼鼠的光谱和时间IRF成熟被破坏时，表明暴露于图案声输入的重要性。随后，当动物成年后被送回标准的住房条件时，它们被重新规范化。
The mechanisms by which hearing selectivity is elaborated and refined in early development are very incompletely determined. In this study, we documented contributions of progressively maturing inhibitory influences on the refinement of spectral and temporal response properties in the primary auditory cortex. Inhibitory receptive fields (IRFs) of infant rat auditory cortical neurons were spectrally far broader and had extended over far longer duration than did those of adults. The selective refinement of IRFs was delayed relative to that of excitatory receptive fields by an approximate to 2-week period that corresponded to the critical period for plasticity. Local application of a GABA(A) receptor antagonist revealed that intracortical inhibition contributes to this progressive receptive field maturation for response selectivity in frequency. Conversely, it had no effect on the duration of IRFs or successive-signal cortical response recovery times. The importance of exposure to patterned acoustic inputs was suggested when both spectral and temporal IRF maturation were disrupted in rat pups reared in continuous, moderate-intensity noise. They were subsequently renormalized when animals were returned to standard housing conditions as adults.