Saunders J C, Dolgin K G, Lowry L D
Brain Res. 1980 Apr 7;187(1):69-79. doi: 10.1016/0006-8993(80)90495-3.
The present study was designed to examine the ontogeny of frequency selectivity in the neonatal auditory system. Mice were tested between 12 and 65 days of age. At each age two measures of auditory sensitivity were made from cochlear nucleus evoked responses. Tone-burst evoked-response thresholds in the quiet were determined for frequencies between 1.0 and 39.0 kHz. A two-tone simultaneous masking procedure was then used to obtain evoked response tuning curves. The frequency selectivity of the tuning curves was quantified by calculating a Q ratio. The results show that tuning is poor in neonates but rapidly improves to adult-like levels within 5-16 days after the inception of auditory function. The data also indicate that the development of frequency selectivity varies directly with the maturation of threshold sensitivity.
本研究旨在考察新生儿听觉系统频率选择性的个体发生。对12至65日龄的小鼠进行测试。在每个年龄阶段，通过耳蜗核诱发反应来测量两种听觉敏感性指标。测定了1.0至39.0千赫兹频率范围内安静状态下短纯音诱发反应的阈值。然后采用双音同时掩蔽程序来获得诱发反应调谐曲线。通过计算Q比值来量化调谐曲线的频率选择性。结果表明，新生儿的调谐能力较差，但在听觉功能开始后的5至16天内迅速提高到类似成年动物的水平。数据还表明，频率选择性的发展与阈值敏感性的成熟直接相关。
