Exposure to a novel stimulus environment alters patterns of lateralization in avian auditory cortex.
Exposure to a novel stimulus environment alters patterns of lateralization in avian auditory cortex.
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暴露于新的刺激环境会改变鸟类听觉皮层的偏侧化模式。
DOI：
10.1016/j.neuroscience.2014.10.022
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发表时间：
2015
期刊：
影响因子：
3.3
通讯作者：
Vicario,DS
中科院分区：
文献类型：
--
作者：
Yang,LM;Vicario,DS
在开发早期形成的感知过滤器提供了解析传入听觉流的初始手段。然而，这些滤波器可能不会保持固定，并且可以通过随后的听觉输入来更新，使得即使在成年生物体中，听觉系统也经历塑性变化以实现对最近听觉环境的更有效表示。鸣禽是一个很好的模型系统的实验研究的听觉现象，由于许多相似之处之间的歌曲学习鸟类和人类的语言习得。在本研究中，我们探讨了被动沉浸在一个新的异质性听觉环境中的尾内侧新纹状体（NCM），鸣禽听觉区类似于哺乳动物的次级听觉皮层的神经反应的影响。在斑胸草雀，一个被充分研究的鸣禽物种，NCM选择性地响应同种歌曲，并包含一个神经元记忆导师和其他熟悉的同种歌曲。成年雄性斑胸草雀被随机分配到同种或异种听觉环境。暴露2、4或9天后，受试者在清醒电生理记录期间呈现异种和同种歌曲。双侧记录神经反应强度和对测试刺激的适应率。暴露于同种环境声音的控制表现出正常的半球偏侧化模式，具有更高的绝对反应强度和更快的适应在右半球。在异种环境中暴露4或9天的鸟类中，侧化模式完全逆转，在异种环境中暴露2天的鸟类中部分逆转。我们的研究结果表明，短暂的被动暴露于一种新的声音类别是足以引起一个逐渐重组的左，右次级听觉皮层。这些变化可以反映感知滤波器的修改，以形成听觉空间的更有效的表示。
Perceptual filters formed early in development provide an initial means of parsing the incoming auditory stream. However, these filters may not remain fixed, and may be updated by subsequent auditory input, such that, even in an adult organism, the auditory system undergoes plastic changes to achieve a more efficient representation of the recent auditory environment. Songbirds are an excellent model system for experimental studies of auditory phenomena due to many parallels between song learning in birds and language acquisition in humans. In the present study, we explored the effects of passive immersion in a novel heterospecific auditory environment on neural responses in caudo-medial neostriatum (NCM), a songbird auditory area similar to the secondary auditory cortex in mammals. In zebra finches, a well-studied species of songbirds, NCM responds selectively to conspecific songs and contains a neuronal memory for tutor and other familiar conspecific songs. Adult male zebra finches were randomly assigned to either a conspecific or heterospecific auditory environment. After 2, 4 or 9 days of exposure, subjects were presented with heterospecific and conspecific songs during awake electrophysiological recording. The neural response strength and rate of adaptation to the testing stimuli were recorded bilaterally. Controls exposed to conspecific environment sounds exhibited the normal pattern of hemispheric lateralization with higher absolute response strength and faster adaptation in the right hemisphere. The pattern of lateralization was fully reversed in birds exposed to heterospecific environment for 4 or 9 days and partially reversed in birds exposed to heterospecific environment for 2 days. Our results show that brief passive exposure to a novel category of sounds was sufficient to induce a gradual reorganization of the left and right secondary auditory cortices. These changes may reflect modification of perceptual filters to form a more efficient representation of auditory space.