在脆弱X综合征中听觉成熟的改变及其在听力发作发作易感性中的参与
Dorit Möhrle1,2,3, Demi Ma4, Wenyue Xue5
1Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
概括
在小鼠中,脆弱X综合征 (FXS) 显示出与大脑干过激动性相关的听觉过敏和听觉发作 (AGS). 这项研究揭示了听觉发育和神经同步的改变,预测了年轻FXS小鼠的AGS严重程度.
科学领域:
- 神经科学是一个神经科学.
- 遗传学 是一个遗传学.
- 发展生物学 发展生物学
背景情况:
- 听觉过敏和听觉发作 (AGS) 是脆弱X综合征 (FXS) 的关键症状,这是一个遗传性疾病.
- FXS是由FMRP蛋白质的损失引起的,影响神经电路刺激性,特别是在脑干的听觉通路中.
- 以前的研究将FMRP损失与Fmr1淘汰赛 (KO) 小鼠中的异常声学反应和AGS联系起来.
研究的目的:
- 研究Fmr1 KO小鼠在早期和青春期发育期间听觉脑干功能和AGS行为之间的关系.
- 为了比较雄性和雌性Fmr1 KO小鼠与野生型 (WT) 小鼠的听觉处理和AGS表达.
- 探索听觉过敏的发育轨迹及其与神经元活动标志物的相关性.
主要方法:
- 听觉脑干反应 (ABR) 和听觉稳定状态反应 (ASSR) 用于评估听觉通路功能.
- 在暴露于声音时评估了AGS的严重程度,cFos表达量化了下部结合体中的神经元活动.
- 研究对Fmr1 KO和WT小鼠在产后日P20 (婴儿期) 和P32 (青春期) 进行了研究.
主要成果:
- 婴儿Fmr1 KO小鼠表现出更严重的AGS,与上层橄体综合体和下层结合体的听觉反应增加相关,以及神经同步增强.
- 在Fmr1 KO小鼠中,在声波暴露后的下结质中显示出更高的cFos表达.
- 在Fmr1 KO小鼠中,听觉过敏和过度的神经活动随着年龄的增长而下降,但ABR的发育概况仍然有所改变.
结论:
- 在FXS模型中,AGS与听觉系统过度兴奋和听觉成熟障碍有关,特别是在大脑干中.
- 皮层下听力神经元的超同步似乎预测了AGS的严重程度.
- 听觉超响应的短暂性质表明,与FXS相关的听觉处理缺陷背后的发育变化,提供了潜在的治疗点.
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.
Perception of Sound Waves
The human ear is not equally sensitive to all frequencies in the audible range. It may perceive sound waves with the same pressure but different frequencies as having different loudness. Moreover, the perception of sound waves depends on the health of an individual's ears, which decays with age. The health of one's ears may also be affected by regular exposure to loud noises.
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same frequency...
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same frequency...
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...
Auditory Perception
The auditory system is essential for sound perception, utilizing various critical structures. When sound waves enter the outer ear, they travel through the ear canal and cause the eardrum to vibrate. These vibrations are then transmitted to the middle ear, where three tiny bones – the malleus, incus, and stapes – amplify the sound. This amplification is crucial, as it ensures that the sound vibrations are strong enough to be conveyed to the inner ear. These vibrations then reach the cochlea, a...
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...
Factors Affecting Perception
Perception is influenced by perceptual set, context, motivation, and emotion. Perceptual set, or perceptual expectancy, refers to the tendency to perceive things in a particular way, influenced by previous experiences and expectations. This phenomenon affects the interpretation of stimuli, creating a set of mental tendencies and assumptions that impact sensory perceptions of sound, taste, touch, and sight.
An illustrative example of a perceptual set is the scenario where an airline pilot told...
An illustrative example of a perceptual set is the scenario where an airline pilot told...


