This project has been supported by the Japan Science and Technology Agency (JST) PRESTO program.

伦理声明:涉及人类受试者的程序批准了伯尔尼州的伦理委员会（KEK-BE 007/14）。 注意: 图1示出蒙太奇，以及TACS电极的设计（也见讨论），和EEG帽。我们使用EEG帽的弹性材料制成（图1D），以保持附着在头皮上的TACS电极。 1.蒙太奇注意:代表性的结果是从以下TACS电极蒙太奇获得。 <ol><li>蒙太奇1:将两个电极在头皮上，在左背外侧前额叶皮层（DLPFC）（F3电极）和左后顶叶（PPC）（P3电极）（图1A）。 </li><li>蒙太奇2:在头皮上在左边DLPFC（F3电极）将一个TACS电极，以及放置在左肩（图1B）的另一TACS电极。 </li><li>剪辑3:在头皮上在左边的PPC（P3电极）将一个TACS电极，以及放置在左肩（图1C）的另一TACS电极。 </li></ol> 2.准备TACS电极的<ol><li>如果参考TACS电极将被放置在肩部（蒙太奇2和3），为此，首先。 <ol><li>在放置的肩膀电极，准备用磨蚀的皮肤准备凝胶脑电图和心电图的皮肤。使用纱布垫皮肤准备凝胶轻轻擦洗皮肤。 </li><li>应用EEG凝胶的TACS电极放置在肩膀上的电极。 </li><li>固定电极上用胶带的肩膀。 </li></ol></li><li>戴上脑电图帽。调整盖的按国际:10-20系统的电极定位30的位置，并拧紧EEG帽的颚带。 </li><li>标记斑点以指示TACS电极将被定位在头皮上。使用水基于红笔，首先是因为笔的彩色材料的绝缘效果降低，其次，它可以容易地用水洗去。 </li><li>如果没有与笔不延伸到头皮的标记，由于在EEG帽的凝胶插入过于紧（图1D）中的孔中的问题，使用木棒，例如棉签的木柄。 <ol><li>彻底涂料棒的尖端和使用这个技巧，以纪念在头皮上。 </li><li>取下脑电帽和检查标记成功。如果需要的话，填入标记，以便它可以容易地购买有斑点。 </li></ol></li><li>执行以下步骤（2.5.1-2.5.4），取决于参与者的头发的长度。如果参与者具有短发（高达约10厘米），跳过以下步骤（也应该指出的是，某些发型，如恐惧锁，使TACS电极不可能的应用程序）。如果参与者具有较长的海R: <ol><li>放置，其中心标记头皮上的红色斑点的TACS电极。请注意，没有脑电图凝胶应该提上TACS电极在这一刻。 </li><li>螺纹出所有的TACS电极的内环内的头发。 </li><li>绑定螺纹出头发电缆粘合剂。需要注意的是TACS电极周围的头发没有得到约束与由电缆粘合剂的TACS电极。 </li><li>之后头发已经绑定，删除TACS电极。 </li></ol></li><li>适用脑电图凝胶到头皮TACS电极。 <ol><li>之前施加凝胶，头皮和肩TACS电极连接到刺激器，但不要在刺激开启爱好。涂抹薄薄的一层脑电图凝胶到TACS电极。稀疏应用凝胶是非常重要的。 </li><li>小心地将TACS电极后面的头。 <ol><li>如果参与者具有较长的毛发，螺纹结合的头发回通过TACS电极的内孔，没有它uching的TACS电极脑电图凝胶。 </li><li>同时将TACS电极，密切关注红色标记在头皮上被保持在TACS电极中间。一旦TACS电极已被放置在头皮上，它的位置可能不再被改变。 </li><li>从头发中取出电缆粘合剂，一旦TACS电极已被放置。 </li></ol></li><li>打开刺激和监测阻抗。同时认真把一些压力，TACS电极，非常密切地关注了红色标记点始终保持在TACS电极中间。 </li><li>小心提起TACS电极的边缘，并应用一些脑电图胶的头发下面，而不是TACS电极和头发（ 图2）之间。这一点尤其重要，如果参与者有很多头发（见讨论）。 </li><li>继续施加压力的TACS电极，直到阻抗稳定低于10千欧。监测的阻抗如果有必要的TACS stimulator.Carefully TACS电极增加额外的脑电图凝胶，但总是人烟稀少。 注:TACS电极由TACS刺激监测的阻抗的TACS电极，它具有不提供对于每个电极的单独的阻抗值的信息的缺点之间测量。根据不同的脑电放大器系统上，也可能是可以测量通过这个TACS电极阻抗，然后可以分别测量每个电极阻抗。 </li><li>注意任何凝胶从TACS电极逃逸，并去除多余的脑电图凝胶用棉签。 </li></ol></li></ol> 3.安装脑电帽<ol><li>经过TACS电极阻抗达到低于10kΩ的门槛，再次装入脑电帽。提上EEG帽轻轻地和小心，特别是如果EEG帽的材料是弹性的，因为它是否则容易移动的财政的位置在此工序P TACS电极。 注:TACS电极的转变展开了TACS电极下的脑电凝胶引起脑电图凝胶脑电图电极的桥梁。它不拉下一个弹性帽的力量，因为这可能导致其之后出现反弹，这也将导致移动TACS电极是非常重要的。 </li><li>拧紧脑电图帽带。 </li></ol> 4.制备脑电极的<ol><li>适用的适当的粘度脑电图凝胶（如在详细讨论，所讨论的）的EEG电极来创建头皮和EEG电极之间的接触。开始与地面和参考EEG电极。然后，继续到位于TACS电极的中间，并且附近的电极。然后继续剩下的电极（见讨论）。 </li><li>用于围绕TACS电极EEG电极，在一个方向上远离TACS电极注入凝胶与针尖指向。轻轻推下EEģ电极同时施加凝胶，使凝胶不从电极下方逸出。 </li><li>使用木棍增大EEG电极和头皮之间的接触， 如图3，不要使用针尖用于此目的，因为它会刮去参与者的头皮，并且此外不能有效用于此目的。 <ol><li>向下推凝胶对头皮的棒，而且非常轻轻揉搓头皮与杆的顶部有旋转运动。尽量保持棒的角度垂直于头皮设在TACS电极的紧挨电极，坚持下去的侧向运动将电极伸长的凝胶。如果需要的话，采用一些更脑电图凝胶，然后用木棒，进一步提高阻抗。 </li></ol></li><li>为了避免经由泄漏凝胶（图4）桥，节俭了将凝胶用于降低EEG电极的阻抗在TACS电极附近。相反，尝试以降低阻抗尽可能仅使用木棍时，才考虑增加更多的凝胶。 </li><li>一旦良好阻抗已实现了与木棒，小心地插入和打倒针直到针的尖端接触到头皮，然后轻轻涂抹凝胶而把针头从，从而帮助稳定脑电图电极和之间的接触头皮。 </li><li>瞄准低于5kΩ的脑电图电极阻抗，优化数据，因为这降低了噪声干扰和信号失真。 </li><li>一旦阻抗已被降低到适当的水平，测试是否已创建TACS电极和周围EEG电极由于泄漏凝胶之间的任何桥。 <ol><li>申请简要正弦刺激，与实验利益的强度（例如，以1mA峰-峰值）。 注:由于某些系统（见表的材料）的局限性，它是正催产素可以检查网络桥接，而只能通过施加刺激，然后检查脑电放大器的任一通道是否趋于饱和。 </li><li>见任何通道是否饱和，同时刺​​激。 注:由于显而易见的代表性成果，通过泄露的TACS和脑电图电极之间的凝胶桥接将导致饱和脑电放大器的这个通道，并排除这些电极记录数据。这是不可能通过一旦已经建立泄漏凝胶撤消一个桥接。唯一的选择是中断实验。 </li></ol></li><li>检查阻抗一次。然后开始录制。 </li></ol>

<ol>
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The authors have no financial interest to disclose.

该步骤设置并发TACS脑电图实验说明。我们现在来讨论考虑了TACS-脑电图记录，其中前两个因素是成功并发TACS，脑电图记录重要的设置。 避免TACS脑电图电极通过凝胶桥这是至关重要的，以避免通过泄漏脑电图凝胶EEG和TACS电极之间桥接，紧接桥接饱和脑电图放大器的各自的信道。由于这个原因，脑电图凝胶的粘度是成功TACS脑电图记录一个重要的参数。切勿使用液体脑电图凝胶，作为一种流体脑电图凝胶风险从TACS电极和桥梁与相邻的脑电图电极逃逸出来。同时，非常粘稠的脑电图凝胶具有在穿透头发和润滑皮肤，以减少阻抗是不利的。对于在TACS电极附近的脑电图电极，一个更具粘性凝胶bË使用，可以使用一个木棍，以降低阻抗。对于TACS和剩余脑电图电极，用略带粘性较低（但仍不能液）脑电图凝胶。这种类型的凝胶需要较少的努力来降低阻抗。因为难以在TACS电极下刮掉，最好是在这里使用稍微少粘性凝胶。 与TACS神器幅度处理第二个问题是处理TACS神器的大幅度，从10毫伏的脑电图电极的刺激的区域较远，超过100毫伏的刺激0.9毫安当前刺激强度在现场（ 图6） 图7示出刺激强度之间的线性关系（0.5至2.0 mA的峰-峰值）和所述假象的刺激（信道F3）站点所得数值。第一个措施是保持两个EEG和TACS电极的低阻抗。不足在TACS电极和头皮之间的接触将产生较大的TACS工件在脑电图数据的幅度，并且除了应用于电子电流将趋向于不均匀。其次，我们需要考虑的脑电系统的A / D转换器的分辨率级别。 24位A / D转换器理论上可以覆盖一定范围的1.68 V配合0.1μV/位的分辨率。相比之下，16位A / D转换器和一个0.1μV/位分辨率将涵盖6.5 mV的电压范围-过低覆盖TACS神器（ 图6）的范围内。因此，电压记录分辨率需要降低。为了掩饰高达100毫伏工件幅度在刺激部位用16比特系统中，电压记录分辨率理论上需要以上1.53μV/比特被降低到。事实上最近并发TACS脑电图研究具有16位系统不能记录来自刺激​​位点附近的EEG信号由于AMPL的饱和<html> ifier即使当分辨率降低到0.5μV/位12,13。 注意事项减少电极阻抗究其原因，首先开始工作在位于TACS电极中间或附近的脑电图电极的阻抗，是这些脑电图电极需要一定的耐心，细致的工作，以避免桥接。通过启动与这些电极，有时间要等到应用凝胶已经有一些时间来润滑头皮，才考虑采用更脑电图凝胶，如果必要的。附加凝胶应的TACS电极下应用，一旦它已经被放置在头皮上，特别是如果参与者都有很多头发。其原因不仅是减少阻抗 - 好的阻抗，可以实现没有这种步骤 - 但实现与头皮整个TACS电极的表面均匀的连接。 设计与蒙太奇的考虑ntent"&gt; 图1示出的TACS电极的蒙太奇。头皮TACS电极/电极的环状设计和矩形肩TACS电极被描绘。头皮TACS电极的形状允许脑电图电极被放置在受刺激区域的中间。的甜甜圈形设计的一个优点是，它允许从刺激区域中记录的信号。其次，它也可以很容易地保持TACS电极的位置不变。根据刺激的部位，在TACS电极的其他的形状会更适合。从网站的脑电图电极之间进行录制时，矩形TACS电极形状更适合。 应当提醒，TACS电极的形状和位置是不一样的实际受到刺激的区域，但也可以稍微错开31。当决定TACS电极的电流f的位置，建模低估计电极的最佳位置用于靶向感兴趣区域总是强烈建议。 目前的设置是适合于有节奏的活动，在大型网络中的调制。多个协调刺激可以在几个方面13，32，33，34来实现。首先，降低了TACS电极的大小。 Nitsche和他的同事已经表明，一个3.5厘米2电极可调节运动皮层的兴奋性与TDCS 32。第二种方法是利用高清晰度配置13,33,34，其中一个激励电极由四个参考电极包围。高清晰度结构的另一优点是，EEG电极的密度可以增加，因为传统的橡胶电极限制的空间放置EEG电极和64 EEG电极未在当前的设置来实现是可行的。虽然日对于更高的空间特异性ESE的修改需要不同的设置过程，这里所描述的技术方面的考虑仍然适用。 在这个协议中，我们按照国际:10-20系统脑电图电极定位30放置TACS电极。刺激位置的Whileindividual优化将是替代方案中，不同的刺激位置，当在实验中个体间，作为刺激部位相对于所述脑电图记录点改变它可能构成一个问题进行比较。最近展示了结合使用脑磁图（MEG）和TACS的，由Neuling和他的同事35，可能会解决这个问题，TACS神器相关的问题，如空间滤波方法与MEG波束成形允许估计独立的一个TACS网站的大脑活动。 关于蒙太奇，二单极蒙太奇这里描述， 即与extracephali参考电极（图1B和1C），和一个单极蒙太奇， 即，与位于头皮（图1A）两个电极的Ç位置（见电极蒙太奇的进一步分类由纳塞等人36）。另外用单极蒙太奇的优点是避免不感兴趣的研究额外头侧刺激。当选择一个单极蒙太奇主要关注的是电流流动虽然皮质下结构，包括脑干，与调制重要脑干功能的潜在风险。参考电极的两个extracephalic和同侧肩安置已证实不调节脑干功能TDCS 37,38为1mA强度（例如，心脏心率变异性，呼吸速率和血压）。作为一个单极蒙太奇可以具有取决于实验设计明显的优点，有必要为全面测试期间更高的刺激强度和不同单极蒙太奇上重要脑干功能的影响，以及用于比较TDCS和TACS之间的影响力。 需要注意的是高清晰度的配置是用于避免不感兴趣额外头侧刺激双极蒙太奇的问题的另一个解决方案。与由四个参考电极包围一个激励电极的高清晰度的配置导致了四个周围电极下在中心电极和低电流密度下的高电流密度。作为刺激的效果取决于电流的密度，这意味着对于高清晰度的配置中心电极下的单向调制，而相比之下，两个电极结构39的双向调制。 视觉闪烁感知诱发TACS是放置TA时，一个关键的限制因素的刺激强度在额叶CS电极，因视网膜刺激总可捕量。特别是TACS在测试波段频率引起的视觉闪烁，即使在TACS 11的低强度。在我们的经验0.9毫安（峰 - 峰）刺激过DLPFC（F3电极）6赫兹是一个合适的强度电平，以尽量减少视觉闪烁的感觉。 根据实验的设计中，可能有必要，以控制与外部设备的刺激器（如果该功能是用于所使用的刺激物）。我们使用的波形的模拟输出板，以控制刺激器和发送触发器脑电图放大器（见进一步硬件和软件规范在材料表）。万一，这里使用（见表材料 ）的刺激器的，电流输出用遥控器的噪声电平比与嵌入式刺激器接口更高。因此可以选择远程控制的刺激器应选择仅当需要通过实验设计。 脑电图通道故障排除饱和我们已经表明，通过在饱和脑电图放大器的各自的信道泄漏脑电图凝胶结果TACS和EEG电极之间的桥接，并从这些电极（图5A）排除了记录数据。还有其它原因脑电图通道的饱和度。一个原因可能是该放大器的增益是太窄，且电压记录分辨率还未相应调整。在这种情况下，电压记录分辨率需要降低以覆盖TACS工件的幅度的范围内。另一个原因是，在记录部位过于接近的刺激部位。在这种情况下，即使是非常粗糙的电压记录分辨率可能仍然不能覆盖工件的范围。记录应位于进一步远离刺激位置。 目前的职业母育全面描绘了设置和技术方面的考虑并发TACS脑电图实验。使用方法的过程中TACS删除TACS神器和协议好品质录音，TACS将真正成为一个有前途的方法，进一步方便了我们的大脑活动，有节奏的动态变化的最突出的特点的理解。

外的电流在脑的节奏动力学已经观察到了一个世纪1,2。虽然大部分时间被认为是在数据非特异性噪声，今天它们被广泛认为是在大脑3,4,5,6,7,8,9起到信息处理的主要作用。我们的振荡大脑活动和认知过程的特定频率之间的因果关系的理解，通过各种干预措施的发展拥有先进在过去十年中的方法直接调制振荡活动8,10。颅交流电刺激（TACS）就是这样的一个有希望的方法来调制节律活动在脑中10。 TACS是一种非侵入性脑刺激方法，它适用于弱交替（正弦）电流从头皮并调制大脑皮层的兴奋性中的频率特异性方式11，图12，&lt;/ SUP&gt; 13，14，15。虽然是一个有希望的技术为研究大脑中的节律活动的作用，TACS的神经生理机制仍然难以捉摸。一些研究报告TACS对高阶认知过程23,24,25,26,27，28上感知11,13,16,17,18效果和运动功能19,20,21,22，以及效果。神经生理学的证据刺激后夹带脑振荡已经提出使用脑电图13，14，15。目前在人类中用于TACS的效果神经生理学证据刺激12，13，22中报道很少。由于大脑对外界扰动非常强劲，如网上证据对于理解总可捕量的直接神经生理的影响至关重要。 ELECtroencephalography（脑电图），捕捉电生理活动在脑中具有高时间分辨率，是用于研究内源性和夹带的振荡神经活动的理想选择。通过赫尔弗里希和最近的研究同事报道TACS在线神经生理的影响，但在同一时间在TACS测量EEG已经证明困难的，因为突出的TACS神器12，13。对于成功并发TACS脑电图实验，记录良好的品质脑电数据是一个重要方面，这是当前文章的重点，并在同一时间的预处理方法来去除TACS神器也至关重要。在我们的实验室，我们一直在开发我们自己的预处理流水线，允许从脑电数据29去除TACS神器。在这里，我们将介绍如何成功地从刺激的区域，技术因素对成功记录重要记录的EEG信号。

<table><tbody><tr><td>&lt;strong&gt;Stimulator for tACS:&lt;/strong&gt; Eldith DC-Stimulator plus</td><td>NeuroConn GmbH, Germany</td><td></td><td>For remote input, be sure to order a model with this feature enabled</td></tr><tr><td>&lt;strong&gt;Analog Output board for sending triggers:&lt;/strong&gt; Static and Waveform Analog Output board, model NI PCI-6723</td><td>National Instruments, USA</td><td></td><td>13-bit, 32 channels.</td></tr><tr><td>&lt;strong&gt;Matlab and data acquisition toolbox&lt;/strong&gt;</td><td>The MathWorks, Inc., USA</td><td></td><td>The &#039;Data acquisition toolbox&#039; available for MATLAB provides functions to control data acquisition hardware such as an analog output board, produced by several manufacturers.</td></tr><tr><td>&lt;strong&gt;EEG system: &lt;/strong&gt;eegosports, with a 32 channel waveguard EEG cap</td><td>ANT neuro, Netherlands</td><td></td><td></td></tr><tr><td>&lt;strong&gt;tACS electrodes&lt;/strong&gt;</td><td>NeuroConn GmbH, Germany</td><td>305090-05&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 305050</td><td>Materials: conductive-rubber electrodes.&lt;br/&gt; Dimensions of scalp electrodes: Outer &amp;Oslash;: 60 mm, Inner &amp;Oslash;:25 mm (Part# 305090-05) Cut from the original size &amp;Oslash; 75mm&lt;br/&gt; Dimensions of shoulder electrode:&lt;br/&gt; 50 x 50 mm (Part# 305050)</td></tr><tr><td>&lt;strong&gt;EEG gel&lt;/strong&gt;</td><td>Inselspital, Bern, Switzerland</td><td></td><td>Electrode paste, containing abrasives (&lt;em&gt;i.e.&lt;/em&gt; &lt;strong&gt;pumice&lt;/strong&gt;) which scrub the skin, improving the electrode-to-skin contact.</td></tr><tr><td>&lt;strong&gt;Abrasive skin preparing gel for EEG and electrocardiography&lt;/strong&gt;: Nuprep</td><td>Weaver and Company, USA</td><td></td><td></td></tr><tr><td>&lt;strong&gt;Cotton swabs, wooden handle&lt;/strong&gt;</td><td>Salzmann MEDICO, Switzerland</td><td></td><td>Dimensions:&lt;br/&gt; 150 x 1.5 mm; wooden handle &amp;Oslash; 2.2 mm</td></tr><tr><td>&lt;strong&gt;Adhesive tape:&lt;/strong&gt; Leukofix</td><td>BNS medical GmbH, Germany&amp;nbsp;</td><td>04.107.12</td><td></td></tr></tbody></table>

concurrent electroencephalography recording during transcranial alternating current stimulation (tacs)

Oscillatory brain activities are considered to reflect the basis of rhythmic changes in transmission efficacy across brain networks and are assumed to integrate cognitive neural processes. Transcranial alternating current stimulation (tACS) holds the promise to elucidate the causal link between specific frequencies of oscillatory brain activity and cognitive processes. Simultaneous electroencephalography (EEG) recording during tACS would offer an opportunity to directly explore immediate neurophysiological effects of tACS. However, it is not trivial to measure EEG signals during tACS, as tACS creates a huge artifact in EEG data. Here we explain how to set up concurrent tACS-EEG experiments. Two necessary considerations for successful EEG recording while applying tACS are highlighted. First, bridging of the tACS and EEG electrodes via leaking EEG gel immediately saturates the EEG amplifier. To avoid bridging via gel, the viscosity of the EEG gel is the most important parameter. The EEG gel must be viscous to avoid bridging, but at the same time sufficiently fluid to create contact between the tACS electrode and the scalp. Second, due to the large amplitude of the tACS artifact, it is important to consider using an EEG system with a high resolution analog-to-digital (A/D) converter. In particular, the magnitude of the tACS artifact can exceed 100 mV at the vicinity of a stimulation electrode when 1 mA tACS is applied. The resolution of the A/D converter is of importance to measure good quality EEG data from the vicinity of the stimulation site. By following these guidelines for the procedures and technical considerations, successful concurrent EEG recording during tACS will be realized.

例子示从两个不同的记录（ 图5）得到的不成功和成功并发TACS脑电图测量。两个TACS电极放置在头皮上（F3和P3电极）和TACS的强度为0.9 mA的（峰到峰）。在第一个例子中，F3脑电图电极桥接通过凝胶额叶TACS电极（注意，提到"架桥"在整个下面的讨论时，我们表示由脑电图凝胶的直接连接的形成创造TACS和脑电图之间的接触电极）。立即桥接饱和TACS在F3通道和脑电图信号不能被记录（ 图5A）。在第二个例子中，EEG信号被成功地记录，同时施加TACS（图5B）。 为了评估TACS工件的幅度的空间分布，所述在TACS神器幅度从三个科目获得成功的录制过程中进行了计算。 TACS施加到要么DLPFC（F3电极）或PPC（P3电极）。 TACS的强度为0.9 mA的（峰-峰）。它被观察到，TACS工件的峰-峰值幅度呈负与EEG和TACS电极之间的距离的相关性（ 图6A 和 6B）。此外，相对于TACS电极脑电图参考电极的位置也影响了TACS工件横跨脑电图通道幅度的空间分布（图6A 和 6B）。在TACS工件的幅度从10毫伏的范围内，在EEG电极从刺激部位更远，而幅度可达100毫伏在在TACS电极中间脑电图电极。在的附近TACS的电流强度和工件的大小之间的关系TACS电极还检查（图7）。它表现出的线性关系和饱和记录的电压范围时TACS电流强度超过1.6毫安。 <img alt="图1" src="/files/ftp_upload/53527/53527fig1.jpg" /> 图1.蒙太奇的。（A）蒙太奇放在头皮（F3和P3）二TACS电极。 （二）蒙太奇一个TACS电极放在头皮（F3）和一个参考TACS电极置于患侧肩部。 （C）的蒙太奇与一种TACS电极放置在头皮上（P3）和一个参考TACS电极放置在患侧肩部。 （D）的弹性脑电帽持有盖下的地方头皮TACS电极。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53527/53527fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>。 <img alt="图2" src="/files/ftp_upload/53527/53527fig2.jpg" /> 图2. 正确应用一个TACS电极下方附加脑电图凝胶。附加脑电图凝胶是TACS电极下被应用到提高连接到头皮的均匀性。附加凝胶应在头发和头皮上（蓝色箭头）间应用，而不是TACS电极和头发之间，以提高接触。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53527/53527fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/53527/53527fig3.jpg" /> 图3. 提高EEG电极的对头皮的连接。（A）的应用脑电图凝胶用注射器将EEG电极。使用t针的IP来刷掉头发脑电图电极的下方，然后小心地插入和打倒针直到针的尖端接触头皮。应用凝胶而把针头从，创建头皮脑电图电极之间的连接。 （B）使用木棒（例如，棉签或类似的木柄），以进一步改善EEG电极和头皮之间的接触。向下推凝胶对头皮的棒，而且非常轻轻揉搓头皮与杆的顶部有旋转运动。尽量保持棒的角度垂直于头皮设在TACS电极的紧挨电极，坚持下去的侧向运动将电极伸长的凝胶。如果需要的话，采用一些更脑电图凝胶，然后用木棒，进一步提高阻抗。对于地处TACS电极的紧挨电极同样重要的是要谨慎采用更胶FOř提高接触的目的。而尝试改善接触尽可能使用木棒。最后，一旦良好的阻抗已经实现了与木棒，添加一些额外的凝胶稳定脑电图电极和头皮之间的接触。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53527/53527fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图4" src="/files/ftp_upload/53527/53527fig4.jpg" /> 图 泄露脑电图凝胶创建TACS和脑电图电极之间的直接接触，4例。脑电图泄漏凝胶，它创建了TACS和脑电图电极之间的直接接触，观察。在TACS和EEG电极之间的桥接如这可以创建例如，通过在TACS电极附近的TACS电极或脑电图电极下加入脑电图凝胶的过量，或者通过移动电极的TACS。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53527/53527fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图5" src="/files/ftp_upload/53527/53527fig5.jpg" /> 图5. TACS饱和经由凝胶弥合脑电放大器。从两个不同的录音，参考氯丙嗪，原始数据蒙太奇放置在DLPFC（F3电极）和PCC（P3电极）头皮TACS电极中。 （A）的记录，在电极F3的信号由于经由F3脑电图电极和TACS电极之间泄漏脑电图凝胶桥接饱和。 （B）的信号成功地记录所有电极。该TACS神器在F3电极的幅度超过50毫伏。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53527/53527fig5large.jpg" target="_blank">请点击这里查看</a>一个更大的版本这个数字。 <img alt="图6" src="/files/ftp_upload/53527/53527fig6.jpg" /> 图6.跨脑电图渠道TACS器物的大小，对TACS文物峰-峰值幅度，在三个科目（MV）的平均值。该数据是原始数据，参考氯丙嗪。 （A）中的TACS工件与一种头皮TACS电极放置在左侧DLPFC（F3电极）和其它TACS电极放置在左肩（蒙太奇2， 图1B）的蒙太奇中的大小。 （B）中的TACS工件与一种TACS电极放置在左侧的PPC（P3电极）和其它TACS电极蒙太奇放置在左肩期间的幅度（蒙太奇3， 图1C）。 （ 三）脑电图通道的位置。红色:通道下的刺激部位，蓝色:通道的刺激部位紧挨参（粗黑）:参比电极（氯丙嗪）。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53527/53527fig6large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图7" src="/files/ftp_upload/53527/53527fig7.jpg" /> 图7. TACS工件的大小线性相关与刺激的强度。的TACS工件（毫伏）的峰-峰值幅度从在频道F3一个从属。的0.5至2 mA强度在步骤0.1毫安施加。该数据是原始数据，参考氯丙嗪。蒙太奇与头皮TACS电极放置在左侧DLPFC（F3电极）和其它TACS电极放置在左肩（蒙太奇2， 图1B）。该数据显示了刺激强度施加和TACS工件幅度之间的完美的线性关系，在0.5至1.6毫安强度范围。电压分辨率设置为150毫伏，但ACTUA升最大收购范围为161.6毫伏超过该信号饱和。虚线标记的电压的最大范围。随着1.7 mA和更高的，当产生神器幅度均超过161.6 mV的刺激强度，在F3通道饱和。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53527/53527fig7large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Concurrent Electroencephalography Recording During Transcranial Alternating Current Stimulation tACS at JoVE.com

Concurrent Electroencephalography Recording During Transcranial Alternating Current Stimulation tACS

In this article we explain how to set up a concurrent transcranial alternating current stimulation and EEG experiment.

并行脑电图记录在经颅交流电刺激（TACS）

Oscillatory brain activities are considered to reflect the basis of rhythmic changes in transmission efficacy across brain networks and are assumed to ...

concurrent-electroencephalography-recording-during-transcranial

Universidad San Sebastian

Research

JoVE Journal

Behavior

Concurrent Electroencephalography Recording During Transcranial Alternating Current Stimulation (tACS)

14.1K 次观看.  University of Bern. In this article we explain how to set up a concurrent transcranial alternating current stimulation and EEG experiment.

视频: Concurrent Electroencephalography Recording During Transcranial Alternating Current Stimulation tACS

Best Current Practice for Obtaining High Quality EEG Data During Simultaneous fMRI

Simultaneous EEG-fMRI allows the excellent temporal resolution of EEG to be combined with the high spatial accuracy of fMRI. The data from these two modalities can be combined in a number of ways, but all rely on the acquisition of high quality EEG and fMRI data. EEG data acquired during simultaneous fMRI are affected by several artifacts, including the gradient artefact (due to the changing magnetic field gradients required for fMRI), the pulse artefact (linked to the cardiac cycle) and movement artifacts (resulting from movements in the strong magnetic field of the scanner, and muscle activity). Post-processing methods for successfully correcting the gradient and pulse artifacts require a number of criteria to be satisfied during data acquisition. Minimizing head motion during EEG-fMRI is also imperative for limiting the generation of artifacts.
Interactions between the radio frequency (RF) pulses required for MRI and the EEG hardware may occur and can cause heating. This is only a significant risk if safety guidelines are not satisfied. Hardware design and set-up, as well as careful selection of which MR sequences are run with the EEG hardware present must therefore be considered.
The above issues highlight the importance of the choice of the experimental protocol employed when performing a simultaneous EEG-fMRI experiment. Based on previous research we describe an optimal experimental set-up. This provides high quality EEG data during simultaneous fMRI when using commercial EEG and fMRI systems, with safety risks to the subject minimized. We demonstrate this set-up in an EEG-fMRI experiment using a simple visual stimulus. However, much more complex stimuli can be used. Here we show the EEG-fMRI set-up using a Brain Products GmbH (Gilching, Germany) MRplus, 32 channel EEG system in conjunction with a Philips Achieva (Best, Netherlands) 3T MR scanner, although many of the techniques are transferable to other systems.

Simultaneous electroencephalography (EEG) and functional Magnetic Resonance imaging (fMRI) is a powerful neuroimaging tool. However, the inside of an MRI scanner forms a difficult environment for EEG data recording and safety must be considered whenever operating EEG equipment inside a scanner. Here, we present an optimised EEG-fMRI data acquisition protocol.

获得高质量的脑电数据在同步功能磁共振成像的当前最佳实践

Simultaneous  EEG-fMRI allows the excellent temporal resolution of EEG to be combined with the  high spatial accuracy of fMRI. The data  from these two ...

科研

行为学

Simultaneous EEG Monitoring During Transcranial Direct Current Stimulation

Transcranial direct current stimulation (tDCS) is a technique that delivers weak electric currents through the scalp. This constant electric current induces shifts in neuronal membrane excitability, resulting in secondary changes in cortical activity. Although tDCS has most of its neuromodulatory effects on the underlying cortex, tDCS effects can also be observed in distant neural networks. Therefore, concomitant EEG monitoring of the effects of tDCS can provide valuable information on the mechanisms of tDCS. In addition, EEG findings can be an important surrogate marker for the effects of tDCS and thus can be used to optimize its parameters. This combined EEG-tDCS system can also be used for preventive treatment of neurological conditions characterized by abnormal peaks of cortical excitability, such as seizures. Such a system would be the basis of a non-invasive closed-loop device. In this article, we present a novel device that is capable of utilizing tDCS and EEG simultaneously. For that, we describe in a step-by-step fashion the main procedures of the application of this device using schematic figures, tables and video demonstrations. Additionally, we provide a literature review on clinical uses of tDCS and its cortical effects measured by EEG techniques.

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that has shown initial therapeutic effects in several neurological conditions. The main mechanism underlying these therapeutic effects is the modulation of cortical excitability. Therefore, online monitoring of cortical excitability would help guide stimulation parameters and optimize its therapeutic effects. In the present article we review the use of a novel device that combines simultaneous tDCS and EEG monitoring in real time.

同时脑电图监测在经颅直流电刺激

Transcranial  direct current stimulation (tDCS) is a technique that delivers weak electric  currents through the scalp. This constant electric current ...

Stimulating the Lip Motor Cortex with Transcranial Magnetic Stimulation

Transcranial magnetic stimulation (TMS) has proven to be a useful tool in investigating the role of the articulatory motor cortex in speech perception. Researchers have used single-pulse and repetitive TMS to stimulate the lip representation in the motor cortex. The excitability of the lip motor representation can be investigated by applying single TMS pulses over this cortical area and recording TMS-induced motor evoked potentials (MEPs) via electrodes attached to the lip muscles (electromyography; EMG). Larger MEPs reflect increased cortical excitability. Studies have shown that excitability increases during listening to speech as well as during&#160;viewing speech-related movements. TMS can be used also to disrupt the lip motor representation. A 15-min train of low-frequency sub-threshold repetitive stimulation has been shown to suppress motor excitability for a further 15-20 min. This TMS-induced disruption of the motor lip representation impairs subsequent performance in demanding speech perception tasks and modulates auditory-cortex responses to speech sounds. These findings are consistent with the suggestion that the motor cortex contributes to speech perception. This article describes how to localize the lip representation in the motor cortex and how to define the appropriate stimulation intensity for carrying out both single-pulse and repetitive TMS experiments.

Transcranial magnetic stimulation (TMS) has proven to be a useful tool in investigating the role of the articulatory motor cortex in speech perception.&#160; This article describes how to record motor evoked potentials (MEPs) from the lip muscles and how to disrupt the motor lip representation using repetitive TMS.

刺激唇部运动皮层与经颅磁刺激

Transcranial magnetic stimulation (TMS) has proven to be a useful tool in investigating the role of the articulatory motor cortex in speech perception. ...

Transcranial Direct Current Stimulation and Simultaneous  Functional Magnetic Resonance Imaging

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses weak electrical currents administered to the scalp to manipulate cortical excitability and, consequently, behavior and brain function. In the last decade, numerous studies have addressed short-term and long-term effects of tDCS on different measures of behavioral performance during motor and cognitive tasks, both in healthy individuals and in a number of different patient populations. So far, however, little is known about the neural underpinnings of tDCS-action in humans with regard to large-scale brain networks. This issue can be addressed by combining tDCS with functional brain imaging techniques like functional magnetic resonance imaging (fMRI) or electroencephalography (EEG).
In particular, fMRI is the most widely used brain imaging technique to investigate the neural mechanisms underlying cognition and motor functions. Application of tDCS during fMRI allows analysis of the neural mechanisms underlying behavioral tDCS effects with high spatial resolution across the entire brain. Recent studies using this technique identified stimulation induced changes in task-related functional brain activity at the stimulation site&#160;and also in more distant brain regions, which were associated with behavioral improvement. In addition, tDCS administered during resting-state fMRI allowed identification of widespread changes in whole brain functional connectivity.
Future studies using this combined protocol should yield new insights into the mechanisms of tDCS action in health and disease and new options for more targeted application of tDCS in research and clinical settings. The present manuscript describes this novel technique in a step-by-step fashion, with a focus on technical aspects of tDCS administered during fMRI.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique. It has successfully been used in basic research and clinical settings to modulate brain function in humans. This article describes the implementation of tDCS and simultaneous functional magnetic resonance imaging (fMRI), to investigate the neural basis of tDCS effects.

经颅直流电刺激和同步功能磁共振成像

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses weak electrical currents administered to the scalp ...

Simultaneous Transcranial Alternating Current Stimulation and Functional Magnetic Resonance Imaging

Transcranial alternating current stimulation (tACS) is a promising tool for noninvasive investigation of brain oscillations. TACS employs frequency-specific stimulation of the human brain through current applied to the scalp with surface electrodes. Most current knowledge of the technique is based on behavioral studies; thus, combining the method with brain imaging holds potential to better understand the mechanisms of tACS. Because of electrical and susceptibility artifacts, combining tACS with brain imaging can be challenging, however, one brain imaging technique that is well suited to be applied simultaneously with tACS is functional magnetic resonance imaging (fMRI). In our lab, we have successfully combined tACS with simultaneous fMRI measurements to show that tACS effects are state, current, and frequency dependent, and that modulation of brain activity is not limited to the area directly below the electrodes. This article describes a safe and reliable setup for applying tACS simultaneously with visual task fMRI studies, which can lend to understanding oscillatory brain function as well as the effects of tACS on the brain.

Transcranial alternating current stimulation (tACS) is a promising tool for noninvasive investigation of brain oscillations, though its effects are not completely understood. This article describes a safe and reliable setup for applying tACS simultaneously with functional magnetic resonance imaging, which can increase understanding oscillatory brain function and effects of tACS.

同时经颅交替电流刺激和功能磁共振成像

Transcranial alternating current stimulation (tACS) is a promising tool for noninvasive investigation of brain oscillations. TACS employs ...

Brain State-dependent Brain Stimulation with Real-time Electroencephalography-Triggered Transcranial Magnetic Stimulation

The effect of a stimulus to the brain depends not only on the parameters of the stimulus but also on the dynamics of brain activity at the time of the stimulation. The combination of electroencephalography (EEG) and transcranial magnetic stimulation (TMS) in a real-time brain state-dependent stimulation system allows the study of relations of dynamics of brain activity, cortical excitability, and plasticity induction. Here, we demonstrate a newly developed method to synchronize the timing of brain stimulation with the phase of ongoing EEG oscillations using a real-time data analysis system. This real-time EEG-triggered TMS of the human motor cortex, when TMS is synchronized with the surface EEG negative peak of the sensorimotor &#181;-alpha (8-14 Hz) rhythm, has shown differential corticospinal excitability and plasticity effects. The utilization of this method suggests that real-time information about the instantaneous brain state can be used for efficacious plasticity induction. Additionally, this approach enables personalized EEG-synchronized brain stimulation which may lead to the development of more effective therapeutic brain stimulation protocols.

This paper describes real-time electroencephalography-triggered transcranial magnetic stimulation to study and modulate human brain networks.

脑状态依赖性脑刺激与实时脑脑图触发颅内磁刺激

The effect of a stimulus to the brain depends not only on the parameters of the stimulus but also on the dynamics of brain activity at the time of the ...

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 ...

神经科学

Effects of Transcranial Alternating Current Stimulation on the Primary Motor Cortex by Online Combined Approach with Transcranial Magnetic Stimulation

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific frequency and in turn modulate ongoing cortical oscillatory activity. This neurotool allows the establishment of a causal link between endogenous oscillatory activity and behavior. Most of the tACS studies have shown online effects of tACS. However, little is known about the underlying action mechanisms of this technique because of the AC-induced artifacts on Electroencephalography (EEG) signals. Here we show a unique approach to investigate online physiological frequency-specific effects of tACS of the primary motor cortex (M1) by using single pulse Transcranial Magnetic Stimulation (TMS) to probe cortical excitability changes. In our setup, the TMS coil is placed over the tACS electrode while Motor Evoked Potentials (MEPs) are collected to test the effects of the ongoing M1-tACS. So far, this approach has mainly been used to study the visual and motor systems. However, the current tACS-TMS setup can pave the way for future investigations of cognitive functions. Therefore, we provide a step-by-step manual and video guidelines for the procedure.

Transcranial Alternating Current Stimulation (tACS) allows the modulation of cortical excitability in a frequency-specific fashion. Here we show a unique approach which combines online tACS with single pulse Transcranial Magnetic Stimulation (TMS) in order to "probe" cortical excitability by means of Motor Evoked Potentials.

经颅磁刺激在线联合方法对经颅交流电刺激对原发性运动皮层的影响

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific ...

Chronic Transcranial Electrical Stimulation and Intracortical Recording in Rats

Transcranial electrical stimulation (TES) is a powerful and relatively simple approach to diffusely influence brain activity either randomly or in a closed-loop event-triggered manner. Although many studies are focusing on the possible benefits and side-effects of TES in healthy and pathologic brains, there are still many fundamental open questions regarding the mechanism of action of the stimulation. Therefore, there is a clear need for a robust and reproducible method to test the acute and the chronic effects of TES in rodents. TES can be combined with regular behavioral, electrophysiological, and imaging techniques to investigate neuronal networks in vivo. The implantation of transcranial stimulation electrodes does not impose extra constraints on the experimental design while it offers a versatile, flexible tool to manipulate brain activity. Here we provide a detailed, step-by-step protocol to fabricate and implant transcranial stimulation electrodes to influence brain activity in a temporally constrained manner for months.

This detailed protocol describes transcranial stimulation electrode placement on the temporal bone in order to investigate the short- and long-term effects of transcranial electrical stimulation in freely moving rats.

大鼠慢性经颅电刺激及 Intracortical 记录

Transcranial electrical stimulation (TES) is a powerful and relatively simple approach to diffusely influence brain activity either randomly or in a ...

Combined Transcranial Magnetic Stimulation and Electroencephalography of the Dorsolateral Prefrontal Cortex

Transcranial magnetic stimulation (TMS) is a non-invasive method that produces neural excitation in the cortex by means of brief, time-varying magnetic field pulses. The initiation of cortical activation or its modulation depends on the background activation of the neurons of the cortical region activated, the characteristics of the coil, its position and its orientation with respect to the head. TMS combined with simultaneous electrocephalography (EEG) and neuronavigation (nTMS-EEG) allows for the assessment of cortico-cortical excitability and connectivity in almost all cortical areas in a reproducible manner. This advance makes nTMS-EEG a powerful tool that can accurately assess brain dynamics and neurophysiology in test-retest paradigms that are required for clinical trials. Limitations of this method include artifacts that cover the initial brain reactivity to stimulation. Thus, the process of removing artifacts may also extract valuable information. Moreover, the optimal parameters for dorsolateral prefrontal (DLPFC) stimulation are not fully known and current protocols utilize variations from the motor cortex (M1) stimulation paradigms. However, evolving nTMS-EEG designs hope to address these issues. The protocol presented here introduces some standard practices for assessing neurophysiological functioning from stimulation to the DLPFC that can be applied in patients with treatment resistant psychiatric disorders that receive treatment such as transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), magnetic seizure therapy (MST) or electroconvulsive therapy (ECT).

The protocol presented here is for TMS-EEG studies utilizing intracortical excitability test-retest design paradigms. The intent of the protocol is to produce reliable and reproducible cortical excitability measures for assessing neurophysiological functioning related to therapeutic interventions in the treatment of neuropsychiatric diseases such as major depression.

侧前额叶皮质联合经颅磁刺激与脑电图的研究

Transcranial magnetic stimulation (TMS) is a non-invasive method that produces neural excitation in the cortex by means of brief, time-varying magnetic ...