这项工作得到了部分的支持, 重点研究机构, 重点-加州理工研究合作项目通过一笔赠款提供的主旨在2017年。也得到由韩国政府 (MEST) 资助的国家研究基金会 (NRF) 的研究补助金 (NRF-2016R1A2B4015381) 和由科学、信息和通信技术部资助的韩国脑研究所的 KBRI 基础研究方案和未来计划 (17-BR-04)。

动物照料和处理遵循了光州科学和技术研究所 (要点) 的体制方针。
注: 从鼠标中获取视觉诱发电位信号的过程包括四步骤: (1) 传感器组件, (2) 动物制剂, (3) 诱发电位测量, (4) 信号处理。
1. 传感器总成
<ol><li>为一个非侵入电极准备十六针。 注: 每个针型电极由三部分组成: 探头头柱塞、内部弹簧和枪管, 如图 1a所示。每个引脚的长度为13毫米, 可调节的弹簧预长度为1毫米。</li>
	<li>切割两块玻璃纤维衬底 (厚度: 1.5 毫米), 大小为 15 mm x 17 mm (宽度 x 高度)。 注: 导电玻璃纤维基板作为绝缘体, 它将多个信号分离, 同时从鼠标的头皮获得。</li>
	<li>使用精密雕刻机制作直径 1.2 mm 的十六孔, 如图 1c所示。<ol>
<li>均匀地展开探针协调在2毫米的间隔上平的基体: + 7/0, + 2/-2, + 2/0, + 2/+ 2, 0/-4, 0/-2, 0/0 (bregma), 0/+ 2, 0/+ 4,-2/-3,-2/-1,-2/+ 1,-2/-3,-4,-4/+ 2 (前后/横向与 bregma 的基础, 在 mm)24,25,26。</li>
	</ol>
</li>
	<li>堆叠两个衬底和应用一滴快速作用胶粘剂之间的基板层, 产生一个双层的3毫米厚度支持十六稳定和平行电极在信号采集。</li>
	<li>手动将十六电极安装到衬底上。 注: 较小的孔直径会在同一长度下停止每个电极。每个孔直径略小于一个枪管的最厚直径 (1.3 mm), 这使得电极的紧固没有任何松动。</li>
	<li>焊锡和连接每个电极的结束焊料杯部分的触摸证明连接器。</li>
	<li>用热收缩导管遮盖和隐藏电绝缘的裸接点。</li>
</ol>2. 动物制剂
<ol><li>麻醉用腹腔注射氯胺酮的小鼠: 嗪 100:10 (100 mg/mL:10 毫克/毫升) 混合物与体重10µL/克的数量。 注: 在开始准备前, 检查动物的麻醉是否足够, 通过拉一条腿或调整尾巴。</li>
	<li>应用眼药膏, 用棉签使老鼠的角膜保持湿润。</li>
	<li>用头发剪掉头部和肩膀周围的毛发, 然后传播商业上可用的脱毛霜, 并将其保持在这个区域3-4 分钟。</li>
	<li>用刮刀将所应用的脱毛取出, 然后用湿纸巾擦拭好几次。</li>
</ol>3. 视觉诱发电位测量
注: 整个视觉诱发电位测量过程发生在一个黑暗的法拉第笼 (宽度 x 深度 x 高度:61 x 61 x 60 cm)。
<ol><li>将小鼠的头贴在小鼠耳道上, 并将其紧固到位, 将其安装在立体定向框架上。</li>
	<li>将传感器装入 custom-made 电极支架 (图 1b), 并将传感器支架固定在立体定向帧上, 如图 1d所示。</li>
	<li>找到灵活的 EEG 传感器, 同时考虑参考电极位置和 bregma 位置27。在此之后, 非常小心地降低传感器的垂直方向, 使阵列电极活塞接触鼠标的头皮均匀地弯曲的边缘。 注: 降低的距离小于1毫米, 这是可调整的柱塞长度。</li>
	<li>检查阻抗是否在正确范围内, 从100ω到2ω。当针脚的任何阻抗值超过范围28时, 重新定位电极。</li>
	<li>位置的照片刺激器20厘米远离鼠标的眼睛。</li>
	<li>在开始实验之前, 在黑暗的笼子里调整10分钟的小鼠以适应黑暗的视觉适应。<ol>
<li>设置实验装置的参数如下: 采样频率: 500 赫兹;缺口滤波:60 赫兹;刺激间间隔: 十年代;闪光持续时间:10 毫秒;闪光刺激次数: 100 试验/主题。 注: 闪光灯是白光 LED 照明, 有550± 20% lx, 距离为20厘米。</li>
	</ol>
</li>
</ol>4. 视觉诱发电位反应信号处理程序
<ol><li>
Epoching
	<ol>
<li>为了连续测量串行数据, 从 pre-stimulus 周期 (-300 毫秒) 到刺激周期 (600 毫秒), 根据闪光刺激的开始, 提取每个纪元以创建 single-trial 的诱发电位片段。 注: 由于我们重复提供闪光刺激超过100试验每一个主题, 总共100视觉诱发电位的世纪为每只老鼠在这一步提取。eeg epoching 是从连续测量的 eeg 信号数据中提取特定时间的过程。</li>
	</ol>
</li>
	<li>
重新引用 (平均参考)
	<ol>
<li>计算每个时间点上所有十四电极通道上的 EEG 信号的平均值, 然后从每个通道中减去平均值。重复这一过程的所有视觉诱发时代。</li>
	</ol>
</li>
	<li>使用有限冲激响应 (FIR) 滤波器对 ~ 1-100 赫兹的信号进行带通滤波。</li>
	<li>
基线校正
	<ol>
<li>计算每个通道的 pre-stimulus 周期 (基线周期,-300 ~ 0 毫秒) 的 EEG 信号的平均值, 然后从波形中的每个点减去这个平均值 (-300 ~ 600 毫秒)。这就调整了诱发电位反应的振幅轴, 以利于观察刺激后的脑电波变化。对所有的视觉诱发时代重复这一步。</li>
	</ol>
</li>
	<li>
大视诱发电位反应
	<ol>
<li>平均 single-trial 诱发电位的时代, 为每个频道创造 single-subject 平均的诱发电位波形。然后, 计算每个频道对所有主题的视觉诱发电位响应的总体平均值。</li>
	</ol>
</li>
</ol>

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作者没有什么可透露的。

我们首先关注的是传感器的设计, 通过最小化复杂的手术程序来确定实用性。可变形 EEG 传感器由十六针组成: 十四用于记录, 一个用于地面, 最后一个用于参考电极。每个电极都有柱塞弹簧筒结构, 它将变形能力应用到电极的接触面上, 从而便于从弯曲的小鼠头皮上获得均匀稳定的信号。考虑到动物的福祉, 我们试图通过扩大皮肤电极界面的接触面积29来减轻弹簧力所引起的疼痛, ?...

随着老年痴呆症、老年痴呆症、帕金森综合征和中风的患者数量的增加, 随着人口老龄化和预期寿命的增加, 这些疾病的长期社会负担已还增加了1、2、3。此外, 大多数神经发育疾病, 如精神分裂症和自闭症, 伴有认知和行为障碍, 影响患者的整个生活2,3,4。因此, 研究人员一直在努力改善诊断, 预防, 病理理解, 长期观察和治疗脑部疾病。然而, 问题仍然源于大脑的复杂性和未疾病的病态。翻译研究可能是一个有前途的工具, 以确定解决方案, 因为它使基础研究的转移, 以更短的时间框架内的临床应用, 以较低的成本, 并与更高的成功率在神经科学领域5 ,6,7。翻译研究的另一个目标是检查人体的适用性, 这需要在动物身上进行非侵入性的实验方法, 以便与人类的相同方法进行比较。这些条件已经导致了一些重要的需要发展非侵入性动物的准备方法。一种方法是脑电图 (eeg), 它揭示了皮质脑连接和活动 two-dimensionally 的高时间分辨率, 并受益于非侵入性的协议。事件相关电位记录 (ERP) 是利用 EEG 的典型实验范式之一。
以往的许多研究都采用了非侵入性脑电图方法, 针对人类的对象, 而侵入的方法, 如植入螺钉和极型电极, 已被用于动物研究8,9,10,11,12. 这些方法的信号质量和特性明显依赖于传感器位置的侵入性。为成功的翻译研究, 加纳强调使用相同的条件进行动物研究的那些用于人类研究13。然而, 对于使用动物的基础研究, 非侵入性脑电图方法并不普遍。一种新的方法, 使用非侵入性头皮脑电图传感器系统的重点是实验室小鼠将是一个可靠的和有效的工具, 可用于人类的非侵入性的范式的转化研究, 以及。
众多的鼠标脑电图研究 led 的方式商业化 PCB (印制电路板) 基于多通道电极14,15,16。虽然他们采取了侵入性的方法, 他们有一个有限的通道数 (3-8), 这使得它更难观察 large-scale 脑动力学。此外, 其侵入和高成本也可以限制应用。在另一项研究中, KIST (韩国科学和技术研究所) 开发了40通道 polyimide-based 薄膜电极, 并将其连接到鼠标的头骨17,18,19,20.这项工作获得了最大数量的鼠标脑电图通道。然而, 它是机械薄弱, 不容易重用;因此, 它不适合长期观察, 导致信号减弱, 可能是由免疫反应引起的。同时, Troncoso 和 Mégevand 获得了一种感官诱发电位 (SEP) 对啮齿动物的头骨与三十二不锈钢电极的穿孔聚 (甲基丙烯酸甲酯) (PMMA, 丙烯酸玻璃) 网格21,22,23. 尽管信号质量高, 但电极具有机械弹性和柔软性;因此, 他们在多项实验中遇到了困难。此外, 这种方法仍然是微创的。虽然这些方法提供了良好的信号质量, 但小鼠颅骨的表面积有限, 因此电极的数量受到限制, 使用的是不锈钢极型电极。以前的一些小鼠脑电图研究显示了一些局限性。在本研究中, 我们将展示一种新的测量脑电图的方法, 适用于临床前的翻译研究使用无创干式多通道传感器。
为了克服以往动物脑电图方法的局限性, 包括动物制剂的内在复杂性、侵袭性、高成本、浪费和弱机械强度, 我们试图开发一种新的电极, 它展示了灵活性、干式状态、多通道功能、侵入和性。在下面的协议, 我们将描述的过程, 测量视觉诱发电位 (诱发电位) 记录鼠标头皮使用干燥, 无创, 多通道脑电图传感器。这种方法利用了很容易获得的资源, 从而降低了进入生物医学工程领域的动物实验的门槛。

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visual evoked potential recordings in mice using a dry non-invasive multi-channel scalp eeg sensor

对于实验室小鼠的头皮脑电图研究环境, 我们设计了一种干式16通道脑电图传感器, 由于柱塞弹簧筒结构面和金属的机械强度, 它是无创、可变形和可重用的。材料.从小鼠体内获取视觉诱发电位反应的整个过程包括四步骤: (1) 传感器组件, (2) 动物制剂, (3) 诱发电位测量, (4) 信号处理。本文介绍了具有微米电压信号分辨率和 sub-hundred 毫秒时间分辨率的多小鼠诱发电位反应的有代表性的测量方法。虽然所提出的方法比其他以前报道的动物脑电图获取方法更安全、更方便, 但仍存在一些问题, 包括如何提高信噪比以及如何将这种技术应用于自由运动的动物。该方法利用了较易获得的资源, 并以满意的信号质量显示重复的诱发电位响应。因此, 该方法可用于纵向实验研究和利用非侵入范式进行可靠的平移研究。

我们计算了十一只小鼠诱发电位反应的平均集合, 如图 2所示。这一结果表明, 通过这个实验获得的诱发电位反应从预期 (-300 毫秒) 到 post-stimulation 周期 (600 毫秒), 因为刺激是在时间 0 s。值得注意的是, 信号在刺激后仅波动一段时间 (少于300毫秒), 而信号在 post-stimulation 期间稳定稳定。此外, 十四通道可以分为几个组的基础上, 视觉诱发电位反应, 揭示?...

Watch this Scientific Journal Video about Visual Evoked Potential Recordings in Mice Using a Dry Non-invasive Multi-channel Scalp EEG Sensor at JoVE.com

Visual Evoked Potential Recordings in Mice Using a Dry Non-invasive Multi-channel Scalp EEG Sensor

我们设计了一种干式16通道脑电图传感器, 它是无创、可变形和可重用的。本文介绍了利用干无创多通道脑电传感器对小鼠头皮上的视觉诱发电位 (诱发电位) 信号进行处理的全过程。

干无创多通道头皮脑电传感器在小鼠视觉诱发电位记录中的应用

For scalp EEG research environments with laboratory mice, we designed a dry-type 16 channel EEG sensor which is non-invasive, deformable, and re-usable ...

visual-evoked-potential-recordings-mice-using-dry-non-invasive-multi

Research

JoVE Journal

Neuroscience

8.8K 次观看.  Gwangju Institute of Science and Technology (GIST). 我们设计了一种干式16通道脑电图传感器, 它是无创、可变形和可重用的。本文介绍了利用干无创多通道脑电传感器对小鼠头皮上的视觉诱发电位 (诱发电位) 信号进行处理的全过程。

视频: Visual Evoked Potential Recordings in Mice Using a Dry Non-invasive Multi-channel Scalp EEG Sensor

Electrode Fabrication and Implantation in Aplysia californica for Multi-channel Neural and Muscular Recordings in Intact, Freely Behaving Animals

Recording from key nerves and muscles of Aplysia during feeding behavior allows us to study the patterns of neural control in an intact animal. Simultaneously recording from multiple nerves and muscles gives us precise information about the timing of neural activity. Previous recording methods have worked for two electrodes, but the study of additional nerves or muscles required combining and averaging the recordings of multiple animals, which made it difficult to determine fine details of timing and phasing, because of variability from response to response, and from animal to animal. Implanting four individual electrodes has a very low success rate due to the formation of adhesions that prevent animals from performing normal feeding movements. We developed a new method of electrode fabrication that reduces the bulk of the electrodes inside the animal allowing for normal feeding movements. Using a combination of glues to attach the electrodes results in a more reliable insulation of the electrode which lasts longer, making it possible to record for periods as long as a week. The fabrication technique that we describe could be extended to incorporate several additional electrodes, and would be applicable to vertebrate animals.

Electrode Fabrication and Implantation in Aplysia californica for Multi-channel Neural and Muscular Recordings in Intact, Freely Behaving Animals

A technique is described for implanting four in vivo electrodes to monitor the neuromuscular control of feeding behavior in Aplysia californica.

电极的制作及植入海兔californica完整的，自由的行为的动物多通道的神经和肌肉的录音

Recording from key nerves and muscles of Aplysia during feeding behavior allows us to study the patterns of neural control in an intact animal.  ...

科研

神经科学

High-density EEG Recordings of the Freely Moving Mice using Polyimide-based Microelectrode

Electroencephalogram (EEG) indicates the averaged electrical activity of the neuronal populations on a large-scale level. It is widely utilized as a noninvasive brain monitoring tool in cognitive neuroscience as well as a diagnostic tool for epilepsy and sleep disorders in neurology. However, the underlying mechanism of EEG rhythm generation is still under the veil. Recently introduced polyimide-based microelectrode (PBM-array) for high resolution mouse EEG1 is one of the trials to answer the neurophysiological questions on EEG signals based on a rich genetic resource that the mouse model contains for the analysis of complex EEG generation process. This application of nanofabricated PBM-array to mouse skull is an efficient tool for collecting large-scale brain activity of transgenic mice and accommodates to identify the neural correlates to certain EEG rhythms in conjunction with behavior. However its ultra-thin thickness and bifurcated structure cause a trouble in handling and implantation of PBM-array. In the presented video, the preparation and surgery steps for the implantation of PBM-array on a mouse skull are described step by step. Handling and surgery tips to help researchers succeed in implantation are also provided.

In this article, we described the surgery procedure and handling tips for implantation of ultra-thin polyimide-based microelectrode array (PBM-array) on the mouse skull for acquisition of high-density encephalography (EEG) in a mouse model.

高密度的自由移动，使用基于聚酰亚胺的微电极的小鼠的脑电图记录

Electroencephalogram (EEG) indicates the averaged electrical activity of the neuronal populations on a large-scale level. It is widely utilized as a ...

Dual Electrophysiological Recordings of Synaptically-evoked Astroglial and Neuronal Responses in Acute Hippocampal Slices

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs through activation of their ion channels and neurotransmitter receptors, and process information in part through activity-dependent release of gliotransmitters. Furthermore, astrocytes constitute the main uptake system for glutamate, contribute to potassium spatial buffering, as well as to GABA clearance. These cells therefore constantly monitor synaptic activity, and are thereby sensitive indicators for alterations in synaptically-released glutamate, GABA and extracellular potassium levels. Additionally, alterations in astroglial uptake activity or buffering capacity can have severe effects on neuronal functions, and might be overlooked when characterizing physiopathological situations or knockout mice. Dual recording of neuronal and astroglial activities is therefore an important method to study alterations in synaptic strength associated to concomitant changes in astroglial uptake and buffering capacities. Here we describe how to prepare hippocampal slices, how to identify stratum radiatum astrocytes, and how to record simultaneously neuronal and astroglial electrophysiological responses. Furthermore, we describe how to isolate pharmacologically the synaptically-evoked astroglial currents.

The preparation of acute brain slices from isolated hippocampi, as well as the simultaneous electrophysiological recordings of astrocytes and neurons in stratum radiatum during stimulation of schaffer collaterals is described. The pharmacological isolation of astroglial potassium and glutamate transporter currents is demonstrated.

双突触诱发的星形胶质细胞和神经元的反应，在急性海马脑片电生理记录

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs ...

Extracting Visual Evoked Potentials from EEG Data Recorded During fMRI-guided Transcranial Magnetic Stimulation

Transcranial Magnetic Stimulation (TMS) is an effective method for establishing a causal link between a cortical area and cognitive/neurophysiological effects. Specifically, by creating a transient interference with the normal activity of a target region and measuring changes in an electrophysiological signal, we can establish a causal link between the stimulated brain area or network and the electrophysiological signal that we record. If target brain areas are functionally defined with prior fMRI scan, TMS could be used to link the fMRI activations with evoked potentials recorded. However, conducting such experiments presents significant technical challenges given the high amplitude artifacts introduced into the EEG signal by the magnetic pulse, and the difficulty to successfully target areas that were functionally defined by fMRI. Here we describe a methodology for combining these three common tools: TMS, EEG, and fMRI. We explain how to guide the stimulator&#39;s coil to the desired target area using anatomical or functional MRI data, how to record EEG during concurrent TMS, how to design an ERP study suitable for EEG-TMS combination and how to extract reliable ERP from the recorded data. We will provide representative results from a previously published study, in which fMRI-guided TMS was used concurrently with EEG to show that the face-selective N1 and the body-selective N1 component of the ERP are associated with distinct neural networks in extrastriate cortex. This method allows us to combine the high spatial resolution of fMRI with the high temporal resolution of TMS and EEG and therefore obtain a comprehensive understanding of the neural basis of various cognitive processes.

This paper describes a method for collecting and analyzing electroencephalography (EEG) data during concurrent transcranial magnetic stimulation (TMS) guided by activations revealed with functional magnetic resonance imaging (fMRI). A method for TMS artifact removal and extraction of event related potentials is described as well as considerations in paradigm design and experimental setup.

提取脑电数据视觉诱发电位记录在功能磁共振成像引导下经颅磁刺激

Transcranial Magnetic Stimulation (TMS) is an effective method for establishing a causal link between a cortical area and cognitive/neurophysiological ...

Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to monitor the disease course in the follow-up period. Changes in the VEP parameters closely correlate with pathological damage in the optic nerve. This protocol provides a detailed description about the rodent model of optic nerve microinjection, in which a partial demyelination lesion is produced in the optic nerve. VEP recording techniques are also discussed. Using skull implanted electrodes, we are able to acquire reproducible intra-session and between-session VEP traces. VEPs can be recorded on individual animals over a period of time to assess the functional changes in the optic nerve longitudinally. The optic nerve demyelination model, in conjunction with the VEP recording protocol, provides a tool to investigate the disease processes associated with demyelination and remyelination, and can potentially be employed to evaluate the effects of new remyelinating drugs or neuroprotective therapies.

Focal demyelination is induced in the optic nerve using lysolecithin microinjection. Visual evoked potentials are recorded via skull electrodes implanted over the visual cortex to examine the signal conduction along the visual pathway in vivo. This protocol details the surgical procedures underlying electrode implantation and optic nerve microinjection.

在实验视神经脱髓鞘模型大鼠视觉诱发电位记录

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to ...

Simultaneous Recording of Electroretinography and Visual Evoked Potentials in Anesthetized Rats

The electroretinogram (ERG) and visual evoked potential (VEP) are commonly used to assess the integrity of the visual pathway. The ERG measures the electrical responses of the retina to light stimulation, while the VEP measures the corresponding functional integrity of the visual pathways from the retina to the primary visual cortex following the same light event. The ERG waveform can be broken down into components that reflect responses from different retinal neuronal and glial cell classes. The early components of the VEP waveform represent the integrity of the optic nerve and higher cortical centers. These recordings can be conducted in isolation or together, depending on the application. The methodology described in this paper allows simultaneous assessment of retinal and cortical visual evoked electrophysiology from both eyes and both hemispheres. This is a useful way to more comprehensively assess retinal function and the upstream effects that changes in retinal function can have on visual evoked cortical function.

This protocol describes simultaneous measurement of electroretinogram and visual evoked potentials in anesthetized rats.

电图同时记录和麻醉大鼠视觉诱发电位

The electroretinogram (ERG) and visual evoked potential (VEP) are commonly used to assess the integrity of the visual pathway. The ERG measures the ...

A Visual Guide to Sorting Electrophysiological Recordings Using 'SpikeSorter'

Few stand-alone software applications are available for sorting spikes from recordings made with multi-electrode arrays. Ideally, an application should be user friendly with a graphical user interface, able to read data files in a variety of formats, and provide users with a flexible set of tools giving them the ability to detect and sort extracellular voltage waveforms from different units with some degree of reliability. Previously published spike sorting methods are now available in a software program, SpikeSorter, intended to provide electrophysiologists with a complete set of tools for sorting, starting from raw recorded data file and ending with the export of sorted spikes times. Procedures are automated to the extent this is currently possible. The article explains and illustrates the use of the program. A representative data file is opened, extracellular traces are filtered, events are detected and then clustered. A number of problems that commonly occur during sorting are illustrated, including the artefactual over-splitting of units due to the tendency of some units to fire spikes in pairs where the second spike is significantly smaller than the first, and over-splitting caused by slow variation in spike height over time encountered in some units. The accuracy of SpikeSorter's performance has been tested with surrogate ground truth data and found to be comparable to that of other algorithms in current development.

The article shows how to use the program SpikeSorter to detect and sort spikes in extracellular recordings made with multi-electrode arrays.

可视化指南排序的电生理记录使用"SpikeSorter"

Few stand-alone software applications are available for sorting spikes from recordings made with multi-electrode arrays. Ideally, an application should be ...

Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings

Previous studies have shown that neurons in parieto-frontal areas of the macaque brain can be highly selective for real-world objects, disparity-defined curved surfaces, and images of real-world objects (with and without disparity) in a similar manner as described in the ventral visual stream. In addition, parieto-frontal areas are believed to convert visual object information into appropriate motor outputs, such as the pre-shaping of the hand during grasping. To better characterize object selectivity in the cortical network involved in visuomotor transformations, we provide a battery of tests intended to analyze the visual object selectivity of neurons in parieto-frontal regions.

A detailed protocol to analyze object selectivity of parieto-frontal neurons involved in visuomotor transformations is presented.

用单单元记录法研究猕猴背视流中的对象表示

Previous studies have shown that neurons in parieto-frontal areas of the macaque brain can be highly selective for real-world objects, disparity-defined ...

Cochlear Implant Surgery and Electrically-evoked Auditory Brainstem Response Recordings in C57BL/6 Mice

Cochlear implants (CIs) are neuroprosthetic devices that can provide a sense of hearing to deaf people. However, a CI cannot restore all aspects of hearing. Improvement of the implant technology is needed if CI users are to perceive music and perform in more natural environments, such as hearing out a voice with competing talkers, reflections, and other sounds. Such improvement requires experimental animals to better understand the mechanisms of electric stimulation in the cochlea and its responses in the whole auditory system. The mouse is an increasingly attractive model due to the many genetic models available. However, the limited use of this species as a CI model is mainly due to the difficulty of implanting small electrode arrays. More details about the surgical procedure are therefore of great interest to expand the use of mice in CI research.
In this report, we describe in detail the protocol for acute deafening and cochlear implantation of an electrode array in the C57BL/6 mouse strain. We demonstrate the functional efficacy of this procedure with electrically-evoked auditory brainstem response (eABR) and show examples of facial nerve stimulation. Finally, we also discuss the importance of including a deafening procedure when using a normally hearing animal. This mouse model provides a powerful opportunity to study genetic and neurobiological mechanisms that would be of relevance for CI users.

Animal models of cochlear implants can advance knowledge of the technological bases of treating permanent sensorineural hearing loss with electrical stimulation. This study presents a surgical protocol for acute deafening and cochlear implantation of an electrode array in mice as well as the functional assessment with auditory brainstem response.

c57bl6 小鼠耳蜗植入术与电唤起脑干反应记录

Cochlear implants (CIs) are neuroprosthetic devices that can provide a sense of hearing to deaf people. However, a CI cannot restore all aspects of ...

Noninvasive EEG Recordings from Freely Moving Piglets

The method allows the recording of high-quality electroencephalograms (EEGs) from freely moving piglets directly in the pigpen. We use a one-channel telemetric electroencephalography system in combination with standard self-adhesive hydrogel electrodes. The piglets are calmed down without the use of sedatives. After their release into the pigpen, the piglets behave normally&#8212;they drink and sleep in the same cycle as their siblings. Their sleep phases are used for the EEG recordings.

Here, we present a protocol to record telemetric electroencephalograms (EEGs) from freely moving piglets directly in the pigpen without the use of a sedative, making it possible to record typical EEG patterns during non-REM sleep, like spindle bursts.

自由移动仔猪的无创脑电图记录

The method allows the recording of high-quality electroencephalograms (EEGs) from freely moving piglets directly in the pigpen. We use a one-channel ...