Graber Michael H, Helmchen Fritjof, Hahnloser Richard H R
Institute of Neuroinformatics and Neuroscience Center Zurich, University of Zurich / ETH Zurich, Zurich, Switzerland.
PLoS One. 2013 Dec 3;8(12):e81177. doi: 10.1371/journal.pone.0081177. eCollection 2013.
Motor functions are often guided by sensory experience, most convincingly illustrated by complex learned behaviors. Key to sensory guidance in motor areas may be the structural and functional organization of sensory inputs and their evoked responses. We study sensory responses in large populations of neurons and neuron-assistive cells in the songbird motor area HVC, an auditory-vocal brain area involved in sensory learning and in adult song production. HVC spike responses to auditory stimulation display remarkable preference for the bird's own song (BOS) compared to other stimuli. Using two-photon calcium imaging in anesthetized zebra finches we measure the spatio-temporal structure of baseline activity and of auditory evoked responses in identified populations of HVC cells. We find strong correlations between calcium signal fluctuations in nearby cells of a given type, both in identified neurons and in astroglia. In identified HVC neurons only, auditory stimulation decorrelates ongoing calcium signals, less for BOS than for other sound stimuli. Overall, calcium transients show strong preference for BOS in identified HVC neurons but not in astroglia, showing diversity in local functional organization among identified neuron and astroglia populations.
运动功能通常受感觉经验的引导，复杂的学习行为最有力地说明了这一点。感觉输入及其诱发反应的结构和功能组织可能是运动区域感觉引导的关键。我们研究鸣禽运动区域HVC中大量神经元和神经辅助细胞的感觉反应，HVC是一个参与感觉学习和成年鸣唱产生的听觉-发声脑区。与其他刺激相比，HVC对听觉刺激的尖峰反应对鸟类自身的歌声（BOS）表现出显著的偏好。在麻醉的斑马雀中使用双光子钙成像，我们测量了HVC细胞特定群体中基线活动和听觉诱发反应的时空结构。我们发现在特定类型的相邻细胞中，无论是在已识别的神经元还是在星形胶质细胞中，钙信号波动之间都存在很强的相关性。仅在已识别的HVC神经元中，听觉刺激使正在进行的钙信号去相关，对BOS的去相关程度低于对其他声音刺激的去相关程度。总体而言，钙瞬变在已识别的HVC神经元中对BOS表现出强烈偏好，但在星形胶质细胞中则不然，这表明已识别的神经元和星形胶质细胞群体之间在局部功能组织上存在差异。
