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 motivar animais em labirintos seco. O dispositivo pré-amplificador de baixo custo headstage aqui descrito permitirá aos cientistas para testar hipóteses da função neural em tarefas de água sem a preocupação de danificar equipamentos caros. Este protocolo é utilizado para servir como ponto de partida para o projeto headstage personalizado. O esquema fornecido é facilmente adaptável para incluir mais canais de gravação ou de estimulação e pode ser redimensionada de acordo com os desejos do experimentador. Em particular, mediante a incorporação de setups conector pin comercial, pode-se construir headstages que podem acasalar com placas de interface disponíveis comercialmente eletrodo. Embora o exemplo fornecido neste protocolo fornece fonte de ganho unitário a seguir em cada canal, o leitor interessado pode ajustar esta amplificação, alterando a configuração de resistores e capacitores (veja 2 para uma revisão detalhada dos sistemas de aquisição de dados). Embora as técnicas relacionadas com implante de eletrodos e posicionamento estão fora do escopo deste artigo, usamos a seguinte configuração para gravar a partir de eletrodos de profundidade fixo (Shirvalkar et al. In press, 2010). Mais detalhes de como construir e implantar eletrodos móvel para gravação crônica pode ser encontrada aqui: 3.

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		<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

Nanyang Technological University

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

Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making

Behavioral endocrinological research in humans as well as in animals suggests that testosterone plays a key role in social interactions. Studies in rodents have shown a direct link between testosterone and aggressive behavior1 and folk wisdom adapts these findings to humans, suggesting that testosterone induces antisocial, egoistic or even aggressive behavior2. However, many researchers doubt a direct testosterone-aggression link in humans, arguing instead that testosterone is primarily involved in status-related behavior3,4. As a high status can also be achieved by aggressive and antisocial means it can be difficult to distinguish between anti-social and status seeking behavior.
We therefore set up an experimental environment, in which status can only be achieved by prosocial means. In a double-blind and placebo-controlled experiment, we administered a single sublingual dose of 0.5 mg of testosterone (with a hydroxypropyl-&beta;-cyclodextrin carrier) to 121 women and investigated their social interaction behavior in an economic bargaining paradigm. Real monetary incentives are at stake in this paradigm; every player A receives a certain amount of money and has to make an offer to another player B on how to share the money. If B accepts, she gets what was offered and player A keeps the rest. If B refuses the offer, nobody gets anything. A status seeking player A is expected to avoid being rejected by behaving in a prosocial way, i.e. by making higher offers.
The results show that if expectations about the hormone are controlled for, testosterone administration leads to a significant increase in fair bargaining offers compared to placebo. The role of expectations is reflected in the fact that subjects who report that they believe to have received testosterone make lower offers than those who say they believe that they were treated with a placebo. These findings suggest that the experimental economics approach is sensitive for detecting neurobiological effects as subtle as those achieved by administration of hormones. Moreover, the findings point towards the importance of both psychosocial as well as neuroendocrine factors in determining the influence of testosterone on human social behavior.

The procedure described in this protocol shows that testosterone administration and folk beliefs about testosterone may be associated with directly opposed social behaviors.

Combinando Behavioral Endocrinologia e Economia Experimental: Decisão da testosterona e Social Fazendo

Behavioral endocrinological research in humans as well as in animals suggests that testosterone plays a key role in social interactions. Studies in ...

Neurociência

Combining Transcranial Magnetic Stimulation and fMRI to Examine the Default Mode Network

The default mode network is a group of brain regions that are active when an individual is not focused on the outside world and the brain is at "wakeful rest."1,2,3 It is thought the default mode network corresponds to self-referential or "internal mentation".2,3
It has been hypothesized that, in humans, activity within the default mode network is correlated with certain pathologies (for instance, hyper-activation has been linked to schizophrenia 4,5,6 and autism spectrum disorders 7 whilst hypo-activation of the network has been linked to Alzheimer's and other neurodegenerative diseases 8). As such, noninvasive modulation of this network may represent a potential therapeutic intervention for a number of neurological and psychiatric pathologies linked to abnormal network activation. One possible tool to effect this modulation is Transcranial Magnetic Stimulation: a non-invasive neurostimulatory and neuromodulatory technique that can transiently or lastingly modulate cortical excitability (either increasing or decreasing it) via the application of localized magnetic field pulses.9
In order to explore the default mode network's propensity towards and tolerance of modulation, we will be combining TMS (to the left inferior parietal lobe) with functional magnetic resonance imaging (fMRI). Through this article, we will examine the protocol and considerations necessary to successfully combine these two neuroscientific tools.

In this article, we examine the methodology and considerations relevant to the combination of TMS and fMRI to examine the effects of brain stimulation on the default network.

Combinando Estimulação Magnética Transcraniana e fMRI para o Exame da rede de modo padrão

The default mode network is a group of brain regions that are active when an individual is not focused on the outside world and the brain is at "wakeful ...

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'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 ...

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 ...

Design and Assembly of an Ultra-light Motorized Microdrive for Chronic Neural Recordings in Small Animals

The ability to chronically record from populations of neurons in freely behaving animals has proven an invaluable tool for dissecting the function of neural circuits underlying a variety of natural behaviors, including navigation1 , decision making 2,3, and the generation of complex motor sequences4,5,6. Advances in precision machining has allowed for the fabrication of light-weight devices suitable for chronic recordings in small animals, such as mice and songbirds. The ability to adjust the electrode position with small remotely controlled motors has further increased the recording yield in various behavioral contexts by reducing animal handling.6,7
 Here we describe a protocol to build an ultra-light motorized microdrive for long-term chronic recordings in small animals. Our design evolved from an earlier published version7, and has been adapted for ease-of use and cost-effectiveness to be more practical and accessible to a wide array of researchers. This proven design 8,9,10,11 allows for fine, remote positioning of electrodes over a range of ~ 5 mm and weighs less than 750 mg when fully assembled. We present the complete protocol for how to build and assemble these drives, including 3D CAD drawings for all custom microdrive components.

The design, fabrication and assembly of an ultra-light motorized microdrive is described. The device provides a cost-effective and easy-to-use solution for chronic recordings of single units in small behaving animals.

Concepção e montagem de um Microdrive Ultra-leve motorizada para doenças crônicas Recordings Neurais em Pequenos Animais

The ability to chronically record from populations of neurons in freely behaving animals has proven an invaluable tool for dissecting the function of ...

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 ...

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.