Roberts Todd F, Hisey Erin, Tanaka Masashi, Kearney Matthew G, Chattree Gaurav, Yang Cindy F, Shah Nirao M, Mooney Richard
Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
Department of Neurobiology, Duke University Medical Center, Durham, North Carolina, USA.
Nat Neurosci. 2017 Jul;20(7):978-986. doi: 10.1038/nn.4563. Epub 2017 May 15.
Learning to vocalize depends on the ability to adaptively modify the temporal and spectral features of vocal elements. Neurons that convey motor-related signals to the auditory system are theorized to facilitate vocal learning, but the identity and function of such neurons remain unknown. Here we identify a previously unknown neuron type in the songbird brain that transmits vocal motor signals to the auditory cortex. Genetically ablating these neurons in juveniles disrupted their ability to imitate features of an adult tutor's song. Ablating these neurons in adults had little effect on previously learned songs but interfered with their ability to adaptively modify the duration of vocal elements and largely prevented the degradation of songs' temporal features that is normally caused by deafening. These findings identify a motor to auditory circuit essential to vocal imitation and to the adaptive modification of vocal timing.
学会发声取决于自适应修改发声元素的时间和频谱特征的能力。理论上，向听觉系统传递与运动相关信号的神经元有助于发声学习，但此类神经元的身份和功能仍不清楚。在这里，我们在鸣禽大脑中鉴定出一种以前未知的神经元类型，它将发声运动信号传递到听觉皮层。在幼鸟中通过基因手段消除这些神经元会破坏它们模仿成年导师歌声特征的能力。在成年鸟中消除这些神经元对先前习得的歌声影响不大，但会干扰它们自适应修改发声元素时长的能力，并在很大程度上阻止通常由致聋引起的歌声时间特征的退化。这些发现确定了一条对发声模仿和发声时间的自适应修改至关重要的从运动到听觉的神经回路。
