An overrepresentation of high frequencies in the mouse inferior colliculus supports the processing of ultrasonic vocalizations

Mice are of paramount importance in biomedical research and their vocalizations are a subject of interest for researchers across a wide range of health-related disciplines due to their increasingly important value as a phenotyping tool in models of neural, speech and language disorders. However, the mechanisms underlying the auditory processing of vocalizations in mice are not well understood. The mouse audiogram shows a peak in sensitivity at frequencies between 15-25 kHz, but weaker sensitivity for the higher ultrasonic frequencies at which they typically vocalize. To investigate the auditory processing of vocalizations in mice, we measured evoked potential, single-unit, and multi-unit responses to tones and vocalizations at three different stages along the auditory pathway: the auditory nerve and the cochlear nucleus in the periphery, and the inferior colliculus in the midbrain. Auditory brainstem response measurements suggested stronger responses in the midbrain relative to the peri...小鼠在生物医学研究中具有至关重要的地位，其发声信号因在神经、言语及语言障碍模型中作为表型分析工具的价值日益凸显，因此受到众多健康相关领域研究者的广泛关注。然而，小鼠对发声信号的听觉加工机制目前尚未得到充分阐明。小鼠听阈图（audiogram）显示其听觉敏感度在15~25 kHz频段出现峰值，但对于其通常发声所在的更高超声频段，敏感度则相对较弱。为探究小鼠的发声听觉加工机制，本研究在听觉通路的三个不同阶段——外周的听神经与耳蜗核（cochlear nucleus）、中脑的下丘（inferior colliculus）——测量了其对纯音与发声信号的诱发电位（evoked potential）、单单位及多单位反应。听觉脑干反应（auditory brainstem response）测量结果显示，相较于外周区域，中脑区域的反应更强……