皮质信号传输对于鼠标瞳孔直径的变化是必要的,这些变化是由具有不同对比度的背景声音引起的
Patrick Cody1,2,3, Manoj Kumar4, Thanos Tzounopoulos1,3
1Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 thanos@pitt.edu pac94@pitt.edu.
概括
皮质突触信号传递对于与小鼠听觉对比度相关的瞳孔直径变化至关重要. 这一发现澄清了神经调节如何影响瞳孔大小,有助于理解大脑状态.
科学领域:
- 神经科学是一个神经科学.
- 听觉神经科学 听觉神经科学
- 感官处理 感官处理
背景情况:
- 醒觉期间的瞳孔直径 (PD) 波动与神经调节和神经元活动有关.
- 具体的神经调节变化和PD波动之间的确切因果关系尚不清楚.
- 听觉皮层的声音对比适应涉及神经元增益的变化,这取决于信号传递.
研究的目的:
- 调查皮质神经调节活性,特别是信号传递是否对于光度独立的瞳孔直径变化是必要的.
- 为了确定皮质信号是否调解学生对不同听觉对比度的反应.
- 探索初级听觉皮层 (A1) 神经调节在学生动态中的作用.
主要方法:
- 在清醒的小鼠 (雄性和雌性) 中同时记录瞳孔直径和皮质神经元活动.
- 在适应不同声音对比的过程中测量PD和神经元活动.
- 在A1中成像单细胞神经活动,操纵皮质信号,并评估PD.
主要成果:
- 与低对比度的声音相比,高刺激对比度的声音引起的瞳孔直径的增加更大.
- 皮质突触信号被发现是必要的,这些增加的瞳孔直径在高对比度的声音暴露.
- 初级听觉皮层的神经元增益随着声音对比度的增加而减少,这个过程取决于信号传递.
结论:
- 皮质神经调节性信号传递是一个关键的机制,驱动瞳孔直径的变化,以响应听觉环境.
- 瞳孔尺寸波动可以作为潜在皮质神经调节状态和大脑活动的可靠指标.
- 这项研究推进了对大脑状态,电路和神经调节机制的理解,这些机制反映在瞳孔动态上.
相关概念视频
01:22Hair Cells
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
01:13The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
01:06Echo
The human ear cannot distinguish between two sources of sound if they happen to reach within a specific time interval, typically 0.1 seconds apart. More than this, and they are perceived as separate sources.
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case, then the...
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case, then the...
01:15Depth Perception and Spatial Vision
Depth perception is the ability to perceive objects three-dimensionally. It relies on two types of cues: binocular and monocular. Binocular cues depend on the combination of images from both eyes and how the eyes work together. Since the eyes are in slightly different positions, each eye captures a slightly different image. This disparity between images, known as binocular disparity, helps the brain interpret depth. When the brain compares these images, it determines the distance to an object.