The effects of spectrally imbalanced sound on auditory cortical organization

我们最近的研究发现，在有限的频率范围和中等的音量下被动地接触6到12周的声音会增强，而且不会导致听力丧失，但听觉皮层会产生长期的变化。这些变化在安静暴露后大约3个月才恢复。这可能会引发对“安全声环境”概念的重新思考。我们现在计划将动物暴露在不同类型的声音环境中。我们建议评估声音的各个方面和动物的年龄在诱导这些大脑变化中的重要性。其中一个方面是模拟12小时嘈杂的工作/娱乐环境，穿插12小时安静的夜间时间。通过这种方式，声音暴露在现实生活中的后果可能会被揭示出来。我们将通过记录听觉脑干和皮层的神经活动来评估这些影响。

Our recent finding that passive exposure for six to 12 weeks to sound enhanced in a restricted frequency range and at moderate loudness, and that does not result in hearing loss, produced long-lasting changes in auditory cortex. These changes took about 3 months post-exposure in quiet to recover. This may induce rethinking of the concept of a 'safe acoustic environment'. We now plan to expose animals to various types of sound environments. We propose to assess the importance of various aspects of sound and the age of the animals in inducing these changes in the brain. One of these aspects is to mimic a 12 hour noisy work/recreation condition interspersed with 12 h quiet night time. In this way consequences of the sound exposure for real life situations might be revealed. We will evaluate these effects, by recording neural activity from auditory brainstem and cortex.