Gentner Timothy Q, Margoliash Daniel
Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th Street, Chicago, Illinois 60637, USA.
Nature. 2003 Aug 7;424(6949):669-74. doi: 10.1038/nature01731.
The neural representations associated with learned auditory behaviours, such as recognizing individuals based on their vocalizations, are not well described. Higher vertebrates learn to recognize complex conspecific vocalizations that comprise sequences of easily identified, naturally occurring auditory objects, which should facilitate the analysis of higher auditory pathways. Here we describe the first example of neurons selective for learned conspecific vocalizations in adult animals--in starlings that have been trained operantly to recognize conspecific songs. The neuronal population is found in a non-primary forebrain auditory region, exhibits increased responses to the set of learned songs compared with novel songs, and shows differential responses to categories of learned songs based on recognition training contingencies. Within the population, many cells respond highly selectively to a subset of specific motifs (acoustic objects) present only in the learned songs. Such neuronal selectivity may contribute to song-recognition behaviour, which in starlings is sensitive to motif identity. In this system, both top-down and bottom-up processes may modify the tuning properties of neurons during recognition learning, giving rise to plastic representations of behaviourally meaningful auditory objects.
与习得的听觉行为相关的神经表征，比如基于发声来识别个体，目前尚未得到充分描述。高等脊椎动物学会识别复杂的同种发声，这些发声由易于识别的、自然出现的听觉对象序列组成，这应该有助于对高级听觉通路的分析。在这里，我们描述了成年动物中对习得的同种发声具有选择性的神经元的首个例子——在经过操作性训练以识别同种歌曲的椋鸟中。神经元群体位于前脑非初级听觉区域，与新歌曲相比，对习得歌曲组表现出增强的反应，并根据识别训练的意外情况对习得歌曲类别表现出不同反应。在这个群体中，许多细胞对仅存在于习得歌曲中的特定基序（声学对象）子集具有高度选择性反应。这种神经元选择性可能有助于歌曲识别行为，在椋鸟中，这种行为对基序特征很敏感。在这个系统中，自上而下和自下而上的过程可能在识别学习期间修改神经元的调谐特性，从而产生具有行为意义的听觉对象的可塑性表征。
