Role of Avian Song Nucleus HV c/ Categorical Perception

描述(申请人提供)：这项关于鸣禽鸣唱知觉的研究将有助于理解人类言语知觉的神经机制的长期目标。这些实验的重点是听觉神经元(HVC核)在范畴知觉(CP)中的作用，其中歌曲刺激中的连续差异被认为是离散类别的实例。以前的行为测试已经揭示了沼泽麻雀的鸟鸣特征，这些特征会在沼泽麻雀中引起CP，这些特征将在本研究中重复。在第一个实验中，HVC神经元的细胞内记录将揭示单个神经元是否对歌曲刺激表现出分类反应。如果有明显的范畴反应，比较阈值下和动作电位反应将揭示是否在HVC或突触前部位建立了范畴边界。在第二个实验中，清醒和自由行为的鸟类的HVC神经元的细胞外记录将揭示对歌声刺激的分类行为反应是否伴随着HVC神经元的分类反应。这些数据将为HVC神经元在听觉信号感知中的作用提供新的见解，并可能暗示人类对语言的感知的机械特征。

DESCRIPTION (provided by applicant): This study of song perception by songbirds will contribute to the long-term goal of understanding neural mechanisms underlying human perception of speech. The focus of these experiments is the role of auditory neurons (HVc nucleus) in categorical perception (CP), wherein continuous differences in song stimuli are perceived as instances of discrete categories. Previous behavioral tests have revealed features of birdsong that evoke CP in swamp sparrows, and those features will be duplicated in this study. In the first experiment, intracellular recordings of HVc neurons will reveal whether individual neurons express categorical responses to song stimuli. If categorical responses are evident, comparison of subthreshold and action potential responses will reveal whether categorical boundaries are established in HVc or in sites presynaptic to HVc. In a second experiment, extracellular recordings of HVc neurons in awake and freely behaving birds will reveal whether categorical behavioral responses to song stimuli are accompanied by categorical responses of HVc neurons. These data will provide new insight into the role of HVc neurons in the perception of auditory signals and may suggest mechanistic features of human perception of speech.