一个神经元群代码用于声音本地化
D C Fitzpatrick1, R Batra, T R Stanford
1Department of Anatomy, University of Connecticut Health Center, Farmington 06030-3405, USA. dcf@neuron.uchc.edu
Nature
|August 28, 1997
概括
听觉神经元在信息通过大脑传递时,提高了对声音位置线索的调. 这种改进的神经调提高了声音本地化人口代码的效率.
科学领域:
- 神经科学是一个神经科学.
- 审计系统 审计系统
- 计算神经科学是一种神经科学.
背景情况:
- 听众在声音定位上的准确性超过了单个神经元的空间灵敏度.
- 听觉神经元的广泛空间调表明,对声音定位的种群代码.
- 声间时间差 (ITD) 是低频声音定位的主要提示.
研究的目的:
- 为了研究ITD的神经调如何随着听觉信息上升到大脑而改变ITD.
- 为了确定神经调的敏化是否会影响声音定位群体代码的效率.
主要方法:
- 在听觉系统的不同阶段对低频声音 (<2kHz) 的神经反应的分析.
- 量化神经元调敏度与间隔时间差异 (ITDs) 的量化.
- 基于观察到的神经调属性的群体代码效率的建模.
主要成果:
- 在听觉系统的更高层次上,神经元对ITDs的调变得明显更敏.
- 更清晰的神经调导致声音本地化人口代码的效率提高.
- 需要更少的神经元才能达到特定水平的局部化敏度与利的调.
结论:
- 神经处理提高了声音定位线索的表现,特别是ITDs.
- 增强的神经调可以提高听觉系统中人口编码的效率.
- 这种机制解释了大脑如何实现精确的声音定位,尽管有广泛的神经元调.
相关概念视频
Hearing
When we hear a sound, our nervous system is detecting sound waves—pressure waves of mechanical energy traveling through a medium. The frequency of the wave is perceived as pitch, while the amplitude is perceived as loudness.
Hair 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.
The 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.
The Role of Ion Channels in Neuronal Computation
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Auditory Pathway
Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
Perceiving Loudness, Pitch, and Location
The human brain perceives pitch through two primary mechanisms reflected in place theory and frequency theory. Each mechanism describes how sound waves are interpreted as specific pitches by the brain, offering insights into the intricate processes of auditory perception.
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...


