Vocal production mechanisms in the budgerigar (Melopsittacus undulatus): the presence and implications of amplitude modulation.
Vocal production mechanisms in the budgerigar (Melopsittacus undulatus): the presence and implications of amplitude modulation.
复制标题
虎皮鹦鹉（Melopsittacus undulatus）的发声机制：振幅调制的存在和影响。
DOI：
--
复制
发表时间：
1999
影响因子：
2.4
通讯作者：
P. B. Lavenex
中科院分区：
文献类型：
--
作者：
P. B. Lavenex
在本文中，声学证据的存在下，振幅调制虎皮鹦鹉（Melopsittacus undulatus）接触呼叫和学习英语发声。以前，鹦鹉发声的声学分析仅包括对频谱图或功率谱（来自傅立叶变换）的目视检查。这样的分析使研究人员得出结论，虎皮鹦鹉的发声主要是频率调制，谐波发声。虽然虎皮鹦鹉的叫声已经被证明含有幅度调制的区域，但这一事实的含义在很大程度上被忽视了。振幅调制是两个独立信号之间的非线性相互作用，导致产生新的外差（和差）频率，可以产生非常复杂的傅立叶频谱，可能类似于谐波发声产生的频谱。在本文中，识别信号中存在的振幅调制所需的声学原理进行了概述，其次是数据表明，振幅调制是一个突出的特点，不仅是自然的虎皮鹦鹉联系电话，但也学会了英语发声。它说明了如何分析发声，包含幅度调制，如果它是谐波可能会导致误解的声音和声源的声学和物理特性。振幅调制的影响，研究的个体发育，物理和神经基础的虎皮鹦鹉发声进行了讨论，并提出了一个潜在的模型如何虎皮鹦鹉syrinx可能会产生振幅调制。
In this paper acoustic evidence is presented for the presence of amplitude modulation in budgerigar (Melopsittacus undulatus) contact calls and learned English vocalizations. Previously, acoustic analyses of budgerigar vocalizations have consisted solely of visual inspection of spectrograms or power spectra (derived from Fourier transformation). Such analyses have led researchers to conclude that budgerigar vocalizations are primarily frequency-modulated, harmonic vocalizations. Although budgerigar calls have been shown to contain regions that are modulated in amplitude, the implications of this fact have been largely ignored. Amplitude modulation, the nonlinear interaction between two separate signals that results in the creation of new, heterodyne (sum and difference) frequencies, can produce a very complex Fourier spectrum that may resemble that produced by a harmonic vocalization. In this paper, the acoustic principles necessary for identifying amplitude modulation present in signals are outlined, and followed by data demonstrating that amplitude modulation is a prominent feature not only of natural budgerigar contact calls, but also of their learned English vocalizations. It is illustrated how analyzing a vocalization that contains amplitude modulation as if it were harmonic can result in misinterpretations of the acoustic and physical properties of the sound and sound source. The implications of amplitude modulation for studies of the ontogenetic, physical, and neural basis of budgerigar vocalizations are discussed, and a potential model for how the budgerigar syrinx may function to produce amplitude modulation is proposed.
虎皮鹦鹉（Melopsittacus undulatus）对声音信号的感知。
DOI：
--
发表时间：
1986
期刊：
Experimental biology
影响因子：
--
作者：
Dooling,RJ
通讯作者：
Dooling,RJ
虎皮鹦鹉（Melopsittacus undulatus）的发声发育：接触叫声。
DOI：
10.1037/0735-7036.111.3.226
发表时间：
1997
期刊：
Journal of comparative psychology (Washington, D.C. : 1983)
影响因子：
--
作者：
Brittan-Powell,EF;Dooling,RJ;Farabaugh,SM
通讯作者：
Farabaugh,SM
鸟鸣运动学：麻雀颅骨运动和声学特征的功能相关性。
DOI：
10.1242/jeb.182.1.147
发表时间：
1993
期刊：
The Journal of experimental biology
影响因子：
--
作者：
Westneat,MW;LongJr,JH;Hoese,W;Nowicki,S
通讯作者：
Nowicki,S