Gostaríamos de agradecer Riceberg Justin para assistência técnica nos testes da headstage. Este trabalho foi financiado em parte pelo National Institutes of Grants Saúde MH65658, MH073689 e F30 AG034003-01A1, eo Mount Sinai School of Medicine.

1. Projeto Headstage e Visão geral Fabricação A conclusão headstage sistema de pré-amplificador é composto dos seguintes componentes: <ol><li> Um computador projetado placa de circuito integrado com quatro canais de gravação e dois canais de estimulação. </li><li> Eletrodos que transmitem as gravações e os canais de estimulação para os conectores apropriados no palco cabeça animais. </li><li> Um cabo de corda e de interface que transmite a gravação e canais de estimulação para um comutador de anéis. </li><li> Duas formas de impermeabilização no palco cabeça e no circuito integrado. </li></ol> 2. Design e layout do Headstage Nós projetamos uma placa de circuito impresso integrado com quatro seguidores fonte e 2 passam por canais de estimulação usando um software de CAD comercialmente disponíveis pacote (www.expresspcb.com). Um headstage é projetado, eo padrão de design é lado a lado em uma folha maior de placas de circuito para fornecer headstages muitos a um custo menor. O arquivo CAD é transmitido para a placa de circuito impresso (PCB) de serviços de manufatura, onde dois lados, duas placas de camada são impressos usando camadas de cobre superior e inferior com todos os furos metalizados passar. As placas usam estanho / chumbo traços banhado e almofadas que correspondem ao padrão da indústria laminado FR-4. O PCB pode ser encomendado e enviado no dia útil seguinte. Headstages individuais são cortados da folha PCB grandes azulejos e componentes eletrônicos estão ligados com solda. Um layout de exemplo do headstage utilizado neste protocolo é mostrada (Figura 1). Consulte o site do fabricante para obter instruções detalhadas e dicas sobre concepção de um PCB. 3. Preparação e soldagem de componentes eletrônicos Todos os componentes eletrônicos usados ​​neste protocolo são do Monte Tipo de dispositivo de superfície (SMD). A pegada de cada tipo de dispositivo (resistor capacitor, etc) foi escolhido para minimizar o espaço perdido no headstage, mas maiores componentes SMD pode ser usado se for necessário. <ol><li> Organize seus componentes na placa de circuito e prepará-los para a soldagem. </li><li> Coloque uma pequena quantidade de solda no bloco de estanho / chumbo a ser soldada e trazer a ponta do ferro de solda perto de derreter e aderir a solda para a plataforma. </li><li> Soldar os capacitores em primeiro lugar, resistores seguinte, e então os amplificadores operacionais. </li><li> O op-amps podem ser destruídas por aquecimento mais. Nós usamos uma pistola de calor variável de solda e o menor calor necessário para derreter a solda. Minimizar o tempo de aquecimento usado para fazer uma solda bem. Achamos conveniente criar um pequeno reservatório de solda que flui para o bloco de pegada, aplicando solda ao longo dos traços de comunicação ou de energia. </li><li> Teste que a resistência em toda a sua resistores atende o valor esperado usando um ohmímetro. </li><li> Inspecionar cada bloco de perto para garantir que nenhuma solda é ligar ou ponte blocos adjacentes. Se há uma ponte de solda, aquecer e derreter a solda e usar uma pinça para quebrar a ponte. </li></ol> 4. Montagem e fabricação de Interfaces de Implantes e Tether <ol><li> Inserir um tubo de 23 Ga hipodérmica em uma das portas não utilizadas do ABS 9 pinos soquete para suporte mecânico. </li><li> Corte seis pedaços 1 cm de comprimento de fios magnéticos isolados para conectar os pinos fêmea amphenol à tomada de ABS. </li><li> Soldar os pinos fêmea para o fio magnético usando uma pequena quantidade de solda em cada pino, e pelo aquecimento do pino da ponta. </li><li> Final da solda outros de cada fio magnético nas tomadas ABS. </li><li> Posição do masculino - feminino pinos MillMax sobre as almofadas do lado da corda headstage, e apertar os pinos sobre o PCB para assegurar um ajuste de pressão. Então, cada pino de solda para cada bloco em ordem. </li><li> A posição da porca sobre o conector implante neural e empurrar todos os pinos do sexo feminino nas ranhuras desejado na base de plástico. </li><li> Aplique cola de acrílico (krazy cola) para o topo do conector do soquete ABS e segura-lo para a base do headstage. Cola o tubo de 23Ga para o lado da corda headstage de apoio. </li></ol> 5. Impermeabilização do Headstage <ol><li> Para headstage a prova d&#39;água, envolvem todo o circuito integrado e todas as superfícies metálicas expostas com 5 minutos de epóxi. Permitir 5-10 minutos para a secagem inicial, e 60 minutos para a secagem permanente. </li><li> Putty Tack pôster deve ser aplicada à superfície do 9 pinos ABS em torno da tomada de pinos salientes do sexo feminino a partir do final animal. </li><li> Para impermeabilização máxima, o soquete ABS e plug-ABS deve ser acoplado ea porca deve ser apertada. A pequena faixa de parafilme deve ser envolvido em torno da interface para evitar que a água entre em contato com os conectores de pinos. </li></ol> Segredos para o Sucesso <ol><li> Ao soldar o amplificador operacional, não sobreaquecer o pacote de plástico. Se houverestá queimando visível ou derreter, retire a op-amp e substituí-lo. Aplicação de calor demasiado pode danificar o amplificador operacional sem derreter visível. Teste cada canal com um gerador de função após a soldagem. </li><li> Certifique-se que não há conexões perdidas ou pontes de solda na headstage. Pavio de solda pode ser usado para remover componentes ou vadios solda. </li></ol> 6. Resultados representante Uma gravação boa seguirá um sinal de fonte de entrada sem cortar para dentro e para fora durante o movimento. Para testar a headstage, o usuário deve usar um gerador de função como uma entrada para cada pino de gravação e avaliar as formas de onda no final de saída Moinho Max cabeçalho. Do movimento físico do headstage não deve influenciar a forma de onda gravada. <img src="/files/ftp_upload/2155/2155fig1.jpg" alt="Figura 1" /> Figura 1. (A) Representação esquemática da camada superior da placa de circuito impresso (PCB). Linhas vermelhas indicam os traços de cobre. As linhas amarelas indicam camada de silkscreen opcional para posicionamento de peças eletrônicas. Mostrados são a colocação amplificador operacional (central quadrado amarelo), resistores (menor quadrados amarelos) e capacitores (menor quadrados amarelos). (B) Representação esquemática da camada inferior do PCB. Linhas verdes indicam traços de cobre. Grande área verde cheia representa placa de terra. Um arquivo modelo deste esquema é fornecido para download.

<ol>
	<li>Morris, R. G., Garrud, P., Rawlins, J. N., O'Keefe, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Place+navigation+impaired+in+rats+with+hippocampal+lesions.">Place navigation impaired in rats with hippocampal lesions.</a> Nature. 297, 681-683 (1982).</li><li>Rolston, J. D., Gross, R. E., Potter, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+low-cost+multielectrode+system+for+data+acquisition+enabling+real-time+closed-loop+processing+with+rapid+recovery+from+stimulation+artifacts.+Front.">A low-cost multielectrode system for data acquisition enabling real-time closed-loop processing with rapid recovery from stimulation artifacts. Front.</a> Neuroengineering. 2, 12-12 (2009).</li><li>Fee, M. S., Leonardo, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Miniature+motorized+microdrive+and+commutator+system+for+chronic+neural+recording+in+small+animals.">Miniature motorized microdrive and commutator system for chronic neural recording in small animals.</a> J. Neurosci. Methods. 112, 83-94 (2001).</li><li>Shirvalkar, P. R., Rapp, P. R., Shapiro, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bidirectional+changes+to+hippocampal+theta+gamma+oscillations+predict+memory+for+recent+spatial+episodes.">Bidirectional changes to hippocampal theta gamma oscillations predict memory for recent spatial episodes.</a> Proc Natl Acad Sci U S A. 107 (15), 7054-709 (2010).</li></ol>

Não há conflitos de interesse declarados.

Água labirinto baseado tarefas comportamentais fornecer ferramentas eficazes para investigar as habilidades dos animais cognitivas e representações em tempo real 1. O uso de pouco peso e custo amplificadores headstage eficaz é especialmente crítico em aplicações envolvendo o comportamento neurofisiologia labirinto de água. Porque escapar da água fria fornece a motivação intrínseca para os animais nestas tarefas, o seu comportamento pode ser testado em ensaios repetidos sem as dificuldades de motiv...

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
		
		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Custom designed Integrated Circuit Board</td>
<td>&nbsp;</td>
<td>ExpressPCB.com</td>
<td>Custom</td>
<td>2 layer double sided PCB</td>
</tr>
<tr>
<td>Surface mount Resistors</td>
<td>&nbsp;</td>
<td>Mouser Electronics</td>
<td>RK73B1JTTDD156J</td>
<td>1/10 W, 15 M Ohm 0603, Thick film</td>
</tr>
<tr>
<td>SMD Capacitors </td>
<td>&nbsp;</td>
<td>Newark Electronics</td>
<td>0402YD104KAT2A</td>
<td>0.1 uF (0402)</td>
</tr>
<tr>
<td>SMD Operational Amplifier (quad FET)</td>
<td>&nbsp;</td>
<td>Mouser Electronics</td>
<td>595-TLC2274AIPW</td>
<td>Quad FET - low noise</td>
</tr>
<tr>
<td>9 pin ABS socket</td>
<td>&nbsp;</td>
<td>Ginder Scientific</td>
<td>GS09SKT-220</td>
<td>For animal connection</td>
</tr>
<tr>
<td>9-pin ABS Plug</td>
<td>&nbsp;</td>
<td>Ginder Scientific</td>
<td>GS09PLG-220</td>
<td>To be implanted in animal</td>
</tr>
<tr>
<td>Black Delrin Ring Nut</td>
<td>&nbsp;</td>
<td>Ginder Scientific</td>
<td>GS09BDN-220</td>
<td>&nbsp;</td>
<tr>
<td>Black Delrin Cap Nut</td>
<td>&nbsp;</td>
<td>Ginder Scientific</td>
<td>GS09BDC-220</td>
<td>For protecting animal's implant</td>
</tr>
<tr>
<td>Amphenol pins (male)</td>
<td>&nbsp;</td>
<td>Ginder Scientific</td>
<td>220-P02</td>
<td>&nbsp;</td>
<tr>
<td>Amphenol pins (female)</td>
<td>&nbsp;</td>
<td>Ginder Scientific</td>
<td>220-S02</td>
<td>&nbsp;</td>
<tr>
<td>5-minute epoxy</td>
<td>&nbsp;</td>
<td>Devcon Inc.</td>
<td>S-208 / 20845</td>
<td>&nbsp;</td>
<tr>
<td>Poster Tack Putty</td>
<td>&nbsp;</td>
<td>Elmer's</td>
<td>026000015318</td>
<td>&nbsp;</td>
<tr>
<td>Rosin Core Solder</td>
<td>&nbsp;</td>
<td>Radio Shack</td>
<td>64-009</td>
<td>&nbsp;</td>
<tr>
<td>Soldering Iron </td>
<td>&nbsp;</td>
<td>Weller</td>
<td>Pyropen WSTA6</td>
<td>(adjustable heat)</td>
</tr>
<tr>
<td>Metal tweezers</td>
<td>&nbsp;</td>
<td>Fine Science Tools</td>
<td>Size 5</td>
<td>&nbsp;</td>
<tr>
<td>Parafilm sheets</td>
<td>&nbsp;</td>
<td>American National Can</td>
<td>Parafilm 4" x 250'</td>
<td>&nbsp;</td>
<tr>
<td>Magnet wire</td>
<td>&nbsp;</td>
<td>Belden</td>
<td>8052</td>
<td>Enamel Coated</td>
</tr>
<tr>
<td>Ammeter/ Multimeter</td>
<td>&nbsp;</td>
<td>Fluke Mfg Co.</td>
<td>77 Multimeter</td>
<td>&nbsp;</td>
<tr>
<td>Millmax Double Row Headers</td>
<td>&nbsp;</td>
<td>Millmax / Mouser</td>
<td>575 - 002101</td>
<td>0.05"</td>
</tr>
<tr>
<td>Solder Wick</td>
<td>&nbsp;</td>
<td>Chemtronics</td>
<td>7-10L</td>
<td>0.75 in.</td>
</tr>		</tbody>
		</table>
		</div>

design and construction of a cost effective headstage for simultaneous neural stimulation and recording in the water maze

Amplificadores Headstage e seguidores fonte são comumente usados ​​para estudar a atividade neural em experimentos comportamentais neurofisiologia. Disponíveis produtos comerciais são geralmente caros, não é facilmente personalizado, e não submersível. Aqui nós descrevemos um método para projetar e construir um personalizado, headstage circuito integrado para gravação de 4 canais simultâneos neural e 2 canais de simulação em vigília, os animais se comportando. O headstage é projetado usando um livre, pacote de design CAD disponíveis comercialmente tipo, e pode ser modificada facilmente para acomodar diferentes escalas (por exemplo, para adicionar canais). Uma placa de circuito impresso personalizado é construído usando resistores de montagem em superfície, condensadores e amplificadores operacionais para construir a unidade ganho do circuito seguidor de fonte. O headstage é feita à prova de água com uma combinação de epóxi, parafilme e uma massa de borracha sintética. Temos utilizado com sucesso este dispositivo para registrar potenciais de campo locais e estimular diferentes regiões do cérebro simultaneamente, através de canais independentes em ratos nadando em um labirinto de água. O custo total é &lt;$ 30/unit e podem ser fabricados facilmente.

Watch this Scientific Journal Video about Design and Construction of a Cost Effective Headstage for Simultaneous Neural Stimulation and Recording in the Water Maze at JoVE.com

Design and Construction of a Cost Effective Headstage for Simultaneous Neural Stimulation and Recording in the Water Maze

Nós apresentamos um método de baixo custo para projetar e construir uma luz headstage sistema de pré-amplificador com a gravação simultânea e capacidade neural estimulação. Este dispositivo pode ser impermeabilizado para uso em animais de natação.

Concepção e Construção de um Headstage Custo Efetivo de Estimulação Neural Simultânea e Gravação no labirinto aquático

Headstage preamplifiers and source followers are commonly used to study neural activity in behavioral neurophysiology experiments. Available commercial ...

design-construction-cost-effective-headstage-for-simultaneous-neural

Research

JoVE Journal

Neuroscience

10.6K visualizações.  Mount Sinai School of Medicine. Nós apresentamos um método de baixo custo para projetar e construir uma luz headstage sistema de pré-amplificador com a gravação simultânea e capacidade neural estimulação. Este dispositivo pode ser impermeabilizado para uso em animais de natação.

Vídeo: Design and Construction of a Cost Effective Headstage for Simultaneous Neural Stimulation and Recording in the Water Maze

Morris Water Maze Test for Learning and Memory Deficits in Alzheimer&#39;s Disease Model Mice

The Morris Water Maze (MWM) was first established by neuroscientist Richard G. Morris in 1981 in order to test hippocampal-dependent learning, including acquisition of spatial memoryand long-term spatial memory 1. The MWM is a relatively simple procedure typically consisting of six day trials, the main advantage being the differentiation between the spatial (hidden-platform) and non-spatial (visible platform) conditions 2-4. In addition, the MWM testing environment reduces odor trail interference 5. This has led the task to be used extensively in the study of the neurobiology and neuropharmacology of spatial learning and memory. The MWM plays an important role in the validation of rodent models for neurocognitive disorders such as Alzheimer&#x2019;s Disease 6, 7. In this protocol we discussed the typical procedure of MWM for testing learning and memory and data analysis commonly used in Alzheimer&#x2019;s disease transgenic model mice.

Morris Water Maze Test for Learning and Memory Deficits in Alzheimer&#039;s Disease Model Mice

The Morris Water Maze is a behavioral task to test hippocampal-dependent learning and memory. It has been widely used in the study of neurobiology, neuropharmacology and neurocognitive disorders in rodent models.

Morris Teste Maze Água para déficits de aprendizagem e memória em camundongos Alzheimer Disease Modelo

The Morris Water Maze (MWM) was first established by neuroscientist Richard G. Morris in 1981 in order to test hippocampal-dependent learning, including ...

Neurociência

Optical Recording of Suprathreshold Neural Activity with Single-cell and Single-spike Resolution

Signaling of information in the vertebrate central nervous system is often carried by populations of neurons rather than individual neurons. Also propagation of suprathreshold spiking activity involves populations of neurons. Empirical studies addressing cortical function directly thus require recordings from populations of neurons with high resolution. Here we describe an optical method and a deconvolution algorithm to record neural activity from up to 100 neurons with single-cell and single-spike resolution. This method relies on detection of the transient increases in intracellular somatic calcium concentration associated with suprathreshold electrical spikes (action potentials) in cortical neurons. High temporal resolution of the optical recordings is achieved by a fast random-access scanning technique using acousto-optical deflectors (AODs)1. Two-photon excitation of the calcium-sensitive dye results in high spatial resolution in opaque brain tissue2. Reconstruction of spikes from the fluorescence calcium recordings is achieved by a maximum-likelihood method. Simultaneous electrophysiological and optical recordings indicate that our method reliably detects spikes (&gt;97% spike detection efficiency), has a low rate of false positive spike detection (&lt; 0.003 spikes/sec), and a high temporal precision (about 3 msec) 3. This optical method of spike detection can be used to record neural activity in vitro and in anesthetized animals in vivo3,4.

Understanding the function of the vertebrate central nervous system requires recordings from many neurons because cortical function arises on the level of populations of neurons. Here we describe an optical method to record suprathreshold neural activity with single-cell and single-spike resolution, dithered random-access scanning. This method records somatic fluorescence calcium signals from up to 100 neurons with high temporal resolution. A maximum-likelihood algorithm deconvolves the underlying suprathreshold neural activity from the somatic fluorescence calcium signals. This method reliably detects spikes with high detection efficiency and a low rate of false positives and can be used to study neural populations in vitro and in vivo.

A gravação ótica da atividade neural supraliminares com resolução de uma única célula e um único pico

Signaling of information in the vertebrate central nervous system is often carried by populations of neurons rather than individual neurons. Also ...

Whole Cell Patch Clamp for Investigating the Mechanisms of Infrared Neural Stimulation

It has been demonstrated in recent years that pulsed, infrared laser light can be used to elicit electrical responses in neural tissue, independent of any further modification of the target tissue. Infrared neural stimulation has been reported in a variety of peripheral and sensory neural tissue in vivo, with particular interest shown in stimulation of neurons in the auditory nerve. However, while INS has been shown to work in these settings, the mechanism (or mechanisms) by which infrared light causes neural excitation is currently not well understood. The protocol presented here describes a whole cell patch clamp method designed to facilitate the investigation of infrared neural stimulation in cultured primary auditory neurons. By thoroughly characterizing the response of these cells to infrared laser illumination in vitro under controlled conditions, it may be possible to gain an improved understanding of the fundamental physical and biochemical processes underlying infrared neural stimulation.

Infrared nerve stimulation has been proposed as an alternative to electrical stimulation in a range of nerve types, including those associated with the auditory system. This protocol describes a patch clamp method for studying the mechanism of infrared nerve stimulation in a culture of primary auditory neurons.

Todo patch clamp celular para investigar os mecanismos de estimulação neural Infrared

It has been  demonstrated in recent years that pulsed, infrared laser light can be used to  elicit electrical responses in neural tissue, independent of ...

Simultaneous Electrophysiological Recording and Calcium Imaging of Suprachiasmatic Nucleus Neurons

Simultaneous electrophysiological and fluorescent imaging recording methods were used to study the role of changes of membrane potential or current in regulating the intracellular calcium concentration. Changing environmental conditions, such as the light-dark cycle, can modify neuronal and neural network activity and the expression of a family of circadian clock genes within the suprachiasmatic nucleus (SCN), the location of the master circadian clock in the mammalian brain. Excitatory synaptic transmission leads to an increase in the postsynaptic Ca2+ concentration that is believed to activate the signaling pathways that shifts the rhythmic expression of circadian clock genes. Hypothalamic slices containing the SCN were patch clamped using microelectrodes filled with an internal solution containing the calcium indicator bis-fura-2. After a seal was formed between the microelectrode and the SCN neuronal membrane, the membrane was ruptured using gentle suction and the calcium probe diffused into the neuron filling both the soma and dendrites. Quantitative ratiometric measurements of the intracellular calcium concentration were recorded simultaneously with membrane potential or current. Using these methods it is possible to study the role of changes of the intracellular calcium concentration produced by synaptic activity and action potential firing of individual neurons. In this presentation we demonstrate the methods to simultaneously record electrophysiological activity along with intracellular calcium from individual SCN neurons maintained in brain slices.

Procedures are described to perform simultaneous recordings of membrane potential or current and changes of intracellular calcium concentration. Suprachiasmatic nucleus neurons are filled with the calcium indicator bis-fura-2 using a patch clamp electrode in the whole cell patch clamp configuration.

Simultaneous electrophysiological and fluorescent imaging recording methods were used to study the role of changes of membrane potential or current in ...

Fabrication of High Contact-Density, Flat-Interface Nerve Electrodes for Recording and Stimulation Applications

Many attempts have been made to manufacture multi-contact nerve cuff electrodes that are safe, robust and reliable for long term neuroprosthetic applications. This protocol describes a fabrication technique of a modified cylindrical nerve cuff electrode to meet these criteria. Minimum computer-aided design and manufacturing (CAD and CAM) skills are necessary to consistently produce cuffs with high precision (contact placement 0.51 &#177; 0.04 mm) and various cuff sizes. The precision in spatially distributing the contacts and the ability to retain a predefined geometry accomplished with this design are two criteria essential to optimize the cuff&#39;s interface for selective recording and stimulation. The presented design also maximizes the flexibility in the longitudinal direction while maintaining sufficient rigidity in the transverse direction to reshape the nerve by using materials with different elasticities. The expansion of the cuff&#39;s cross sectional area as a result of increasing the pressure inside the cuff was observed to be 25% at 67 mm Hg. This test demonstrates the flexibility of the cuff and its response to nerve swelling post-implant. The stability of the contacts&#39; interface and recording quality were also examined with contacts&#39; impedance and signal-to-noise ratio metrics from a chronically implanted cuff (7.5 months), and observed to be 2.55 &#177; 0.25 k&#8486; and 5.10 &#177; 0.81 dB respectively.

This article provides a detailed description on the fabrication process of a high contact-density flat interface nerve electrode (FINE). This electrode is optimized for recording and stimulating neural activity selectively within peripheral nerves.

Fabricação de alta Contact densidade, eletrodos nervosas Plano de Interface para gravação e estimulação Applications

Many attempts have been made to manufacture multi-contact nerve cuff electrodes that are safe, robust and reliable for long term neuroprosthetic ...

Time-dependent Increase in the Network Response to the Stimulation of Neuronal Cell Cultures on Micro-electrode Arrays

Micro-electrode arrays (MEAs) can be used to investigate drug toxicity, design paradigms for next-generation personalized medicine, and study network dynamics in neuronal cultures. In contrast with more traditional methods, such as patch-clamping, which can only record activity from a single cell, MEAs can record simultaneously from multiple sites in a network, without requiring the arduous task of placing each electrode individually. Moreover, numerous control and stimulation configurations can be easily applied within the same experimental setup, allowing for a broad range of dynamics to be explored. One of the key dynamics of interest in these in vitro studies has been the extent to which cultured networks display properties indicative of learning. Mouse neuronal cells cultured on MEAs display an increase in response following training induced by electrical stimulation. This protocol demonstrates how to culture neuronal cells on MEAs; successfully record from over 95% of the plated dishes; establish a protocol to train the networks to respond to patterns of stimulation; and sort, plot, and interpret the results from such experiments. The use of a proprietary system for stimulating and recording neuronal cultures is demonstrated. Software packages are also used to sort neuronal units. A custom-designed graphical user interface is used to visualize post-stimulus time histograms, inter-burst intervals, and burst duration, as well as to compare the cellular response to stimulation before and after a training protocol. Finally, representative results and future directions of this research effort are discussed.

Mouse neuronal cells cultured on multi-electrode arrays display an increase in response following electrical stimulation. This protocol demonstrates how to culture neurons, how to record activity, and how to establish a protocol to train the networks to respond to patterns of stimulation.

Aumento Time-dependente na resposta da rede à estimulação de culturas de pilha neuronais em matrizes do micro-elétrodo

Micro-electrode arrays (MEAs) can be used to investigate drug toxicity, design paradigms for next-generation personalized medicine, and study network ...

Simultaneous Recordings of Cortical Local Field Potentials, Electrocardiogram, Electromyogram, and Breathing Rhythm from a Freely Moving Rat

Monitoring the physiological dynamics of the brain and peripheral tissues is necessary for addressing a number of questions about how the brain controls body functions and internal organ rhythms when animals are exposed to emotional challenges and changes in their living environments. In general experiments, signals from different organs, such as the brain and the heart, are recorded by independent recording systems that require multiple recording devices and different procedures for processing the data files. This study describes a new method that can simultaneously monitor electrical biosignals, including tens of local field potentials in multiple brain regions, electrocardiograms that represent the cardiac rhythm, electromyograms that represent awake/sleep-related muscle contraction, and breathing signals, in a freely moving rat. The recording configuration of this method is based on a conventional micro-drive array for cortical local field potential recordings in which tens of electrodes are accommodated, and the signals obtained from these electrodes are integrated into a single electrical board mounted on the animal's head. Here, this recording system was improved so that signals from the peripheral organs are also transferred to an electrical interface board. In a single surgery, electrodes are first separately implanted into the appropriate body parts and the target brain areas. The open ends of all of these electrodes are then soldered to individual channels of the electrical board above the animal's head so that all of the signals can be integrated into the single electrical board. Connecting this board to a recording device allows for the collection of all of the signals into a single device, which reduces experimental costs and simplifies data processing, because all data can be handled in the same data file. This technique will aid the understanding of the neurophysiological correlates of the associations between central and peripheral organs.

This study introduces a method for the simultaneous recording of local field potentials in the brain, electrocardiograms, electromyograms, and breathing signals of a freely moving rat. This technique, which reduces experimental costs and simplifies data analysis, will contribute to the understanding of the interactions between the brain and peripheral organs.

Gravações simultâneas de potenciais de campo corticais Local, eletrocardiograma, eletromiograma e respirar o ritmo de um rato andando livremente

Monitoring the physiological dynamics of the brain and peripheral tissues is necessary for addressing a number of questions about how the brain controls ...

Construction of an Improved Multi-Tetrode Hyperdrive for Large-Scale Neural Recording in Behaving Rats

Monitoring the activity patterns of a large population of neurons over many days in awake animals is a valuable technique in the field of systems neuroscience. One key component of this technique consists of the precise placement of multiple electrodes into desired brain regions and the maintenance of their stability. Here, we describe a protocol for the construction of a 3D-printable hyperdrive, which includes eighteen independently adjustable tetrodes, and is specifically designed for in vivo extracellular neural recording in freely behaving rats. The tetrodes attached to the microdrives can either be individually advanced into multiple brain regions along the track, or can be used to place an array of electrodes into a smaller area. The multiple tetrodes allow for simultaneous examination of action potentials from dozens of individual neurons, as well as local field potentials from populations of neurons in the brain during active behavior. In addition, the design provides for simpler 3D drafting software that can easily be modified for differing experimental needs.

We present the construction of a 3D-printable hyperdrive with eighteen independently adjustable tetrodes. The hyperdrive is designed to record brain activity in freely behaving rats over a period of several weeks.

Construção de um Hyperdrive melhorado de multi Tetrode para gravação Neural em grande escala em comportar-se ratos

Monitoring the activity patterns of a large population of neurons over many days in awake animals is a valuable technique in the field of systems ...

Construction and Implementation of Carbon Fiber Microelectrode Arrays for Chronic and Acute In Vivo Recordings

Multichannel electrode arrays offer insight into the working brain and serve to elucidate neural processes at the single-cell and circuit levels. Development of these tools is crucial for understanding complex behaviors and cognition and for advancing clinical applications. However, it remains a challenge to densely record from cell populations stably and continuously over long time periods. Many popular electrodes, such as tetrodes and silicon arrays, feature large cross-diameters that produce damage upon insertion and elicit chronic reactive tissue responses associated with neuronal death, hindering the recording of stable, continuous neural activity. In addition, most wire bundles exhibit broad spacing between channels, precluding simultaneous recording from a large number of cells clustered in a small area. The carbon fiber microelectrode arrays described in this protocol offer an accessible solution to these concerns. The study provides a detailed method for fabricating carbon fiber microelectrode arrays that can be used for both acute and chronic recordings in vivo. The physical properties of these electrodes make them ideal for stable and continuous long-term recordings at high cell densities, enabling the researcher to make robust, unambiguous recordings from single units across months.

Construction and Implementation of Carbon Fiber Microelectrode Arrays for Chronic and Acute In Vivo Recordings

This protocol describes a procedure for constructing carbon fiber microelectrode arrays for chronic and acute in vivo electrophysiological recordings in mouse (Mus musculus) and ferret (Mustela putorius furo) from multiple brain regions. Each step, following the purchase of raw carbon fibers to microelectrode array implantation, is described in detail, with emphasis on microelectrode array construction.

Construção e Implementação de Matrizes de Microeletrodos de Fibra de Carbono para Gravações In Vivo Crônicas e Agudas

Multichannel electrode arrays offer insight into the working brain and serve to elucidate neural processes at the single-cell and circuit levels. ...

Optrode Array for Simultaneous Optogenetic Modulation and Electrical Neural Recording

During the last decade, optogenetics has become an essential tool for the investigation of neural signaling due to its unique capability of selective neural modulation or monitoring. As specific types of neuronal cells can be genetically modified to express opsin proteins, optogenetics enables optical stimulation or inhibition of the selected neurons. There have been several technological advances in the optical system for optogenetics. Recently, it was proposed to combine the optical waveguide for light delivery with electrophysiological recording to simultaneously monitor the neural responses to optogenetic stimulation or inhibition. In this study, an implantable optrode array (2x2 optical fibers) was developed with embedded multichannel electrodes. 
A light-emitting diode (LED) was employed as a light source, and a microfabricated microlens array was integrated to provide sufficient light power at the tip of the optical fibers. The optrode array system comprises the disposable part and the reusable part. The disposable part has optical fibers and electrodes, while the reusable part has the LED and electronic circuitry for light control and neural signal processing. The novel design of the implantable optrode array system is introduced in the accompanying video in addition to the procedure of the optrode implantation surgery, optogenetic light stimulation, and the electrophysiological neural recording. The results of in vivo experiments successfully showed time-locked neural spikes evoked by the light stimuli from hippocampal excitatory neurons of mice.

Here, we present the fabrication method of an optrode system with optical fibers for light delivery and an electrode array for neural recording. In vivo experiments with transgenic mice expressing channelrhodopsin-2 show the feasibility of the system for simultaneous optogenetic stimulation and electrophysiological recording.

Oprode Array para modulação optogenética simultânea e gravação neural elétrica

During the last decade, optogenetics has become an essential tool for the investigation of neural signaling due to its unique capability of selective ...