Université de Saint-Etienne, Université de Lyon, ENES/CNPS CNRS UMR8195, 42023 Saint-Etienne, France.
Horm Behav. 2012 Apr;61(4):573-81. doi: 10.1016/j.yhbeh.2012.02.004. Epub 2012 Feb 24.
Animal vocalizations convey multiple pieces of information about the sender. Some of them are stable, such as identity or sex, but others are labile like the emotional or motivational state. Only a few studies have examined the acoustic expression of emotional state in non-human animals and related vocal cues to physiological parameters. In this paper, we examined the vocal expression of isolation-induced stress in a songbird, the zebra finch (Taeniopygia guttata). Although songbirds use acoustic communication extensively, nothing is known to date on how they might encode physiological states in their vocalizations. We tested the hypothesis that social isolation in zebra finches induces a rise of plasma corticosterone that modifies the vocal behavior. We monitored plasma corticosterone, as well as call rate and acoustic structure of calls of males in response to the playback of female calls of varied saliences (familiar versus stranger) in two situations: social isolation and social housing. Social isolation induced both a rise in plasma corticosterone, and a range of modifications in males' vocal behavior. Isolated birds showed a lower vocal activity, an abolition of the difference of response between the two stimuli, and evoked calls with longer duration and higher pitch. Because some of these effects were mimicked after oral administration of corticosterone in socially housed subjects, we conclude that corticosterone could be partly responsible for the isolation-related modifications of calls in male zebra finches. To our knowledge, this is the first demonstration of the direct implication of glucocorticoids in the modulation of the structure of vocal sounds.
动物的叫声传达了关于发送者的多种信息。其中一些是稳定的，如身份或性别，但其他的则是不稳定的，如情绪或动机状态。只有少数研究检查了非人类动物的情绪状态的声学表达，并将相关的声音线索与生理参数联系起来。在本文中，我们研究了斑胸草雀（Taeniopygia guttata）在隔离诱导的应激中的叫声表达。尽管鸣禽广泛使用声学通讯，但目前还不知道它们如何在叫声中编码生理状态。我们假设，在斑胸草雀中，社会隔离会引起血浆皮质酮的升高，从而改变其叫声行为。我们监测了雄性的血浆皮质酮、鸣叫率和鸣叫的声学结构，以响应播放不同显著性（熟悉与陌生）的雌性鸣叫，这两种情况分别是：社会隔离和社会居住。社会隔离诱导了雄性血浆皮质酮的升高，以及一系列的叫声行为的改变。孤立的鸟类表现出较低的发声活动、对两种刺激的反应差异的消除，以及发出持续时间更长、音高更高的鸣叫。由于在社会居住的雄性中经口给予皮质酮后，出现了一些类似的效果，我们得出结论，皮质酮可能部分负责雄性斑胸草雀的与隔离相关的叫声改变。据我们所知，这是第一次证明糖皮质激素直接参与了声音结构的调制。
