Name: investigating object representations in the macaque dorsal visual stream using single-unit recordings
Uploaded: 2018-08-01T15:00:00
Description: Watch this Scientific Journal Video about Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings at JoVE.com

Agradecemos a Inez Puttemans, Marc De Paep, Sara De Pril, Wouter Depuydt, Astrid Hermans, Piet Kayenbergh, Gerrit Meulemans, Christophe Ulens e Stijn Verstraeten para assistência técnica e administrativa.

Todos os procedimentos técnicos foram realizados de acordo com guia do Instituto Nacional de saúde para o cuidado e a utilização de animais de laboratório e a UE Directiva 2010/63/UE e foram aprovados pelo Comitê ético de KU Leuven.
1. general métodos para gravações extracelulares em macacos se comportando acordado
<ol><li>Treine os animais para executar as tarefas visuais e motoras necessárias para resolver sua questão de investigação específicos. Certifique-se de que o anima...

<ol>
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Neurosci. 8 (38), 69-86 (2015).</li><li>Theys, T., Pani, P., van Loon, J., Goffin, J., Janssen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selectivity+for+three-dimensional+contours+and+surfaces+in+the+anterior+intraparietal+area.">Selectivity for three-dimensional contours and surfaces in the anterior intraparietal area.</a> J. Neurophysiol. 107 (3), 995-1008 (2012).</li><li>Goffin, J., Janssen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+shape+coding+in+grasping+circuits:+a+comparison+between+the+anterior+intraparietal+area+and+ventral+premotor+area+F5a.">Three-dimensional shape coding in grasping circuits: a comparison between the anterior intraparietal area and ventral premotor area F5a.</a> J. Cogn. Neurosci. 25 (3), 352-364 (2013).</li><li>Raos, V., Umilt&#225;, M. 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Neurosci. 24 (10), 2551-2565 (2004).</li><li>Theys, T., Pani, P., van Loon, J., Goffin, J., Janssen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selectivity+for+three-dimensional+shape+and+grasping-related+activity+in+the+macaque+ventral+premotor+cortex.">Selectivity for three-dimensional shape and grasping-related activity in the macaque ventral premotor cortex.</a> J.Neurosci. 32 (35), 12038-12050 (2012).</li><li>Nelissen, K., Luppino, G., Vanduffel, W., Rizzolatti, G., Orban, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Observing+others:+multiple+action+representation+in+the+frontal+lobe.">Observing others: multiple action representation in the frontal lobe.</a> Science. 310 (5746), 332-336 (2005).</li><li>Janssen, P., Srivastava, S., Ombelet, S., Orban, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coding+of+shape+and+position+in+macaque+lateral+intraparietal+area.">Coding of shape and position in macaque lateral intraparietal area.</a> J. Neurosci. 28 (26), 6679-6690 (2008).</li><li>Romero, M. C., Janssen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Receptive+field+properties+of+neurons+in+the+macaque+anterior+intraparietal+area.">Receptive field properties of neurons in the macaque anterior intraparietal area.</a> J. Neurophysiol. 115 (3), 1542-1555 (2016).</li><li>Decramer, T., Premereur, E., Theys, T., Janssen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multi-electrode+recordings+in+the+macaque+frontal+cortex+reveal+common+processing+of+eye-,+arm-+and+hand+movements.+Program+No.+495.15/GG14.">Multi-electrode recordings in the macaque frontal cortex reveal common processing of eye-, arm- and hand movements. Program No. 495.15/GG14.</a> Neuroscience Meeting Planner. , (2017).</li><li>Pani, P., Theys, T., Romero, M. C., Janssen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Grasping+execution+and+grasping+observation+activity+of+single+neurons+in+macaque+anterior+intraparietal+area.">Grasping execution and grasping observation activity of single neurons in macaque anterior intraparietal area.</a> J. Cogn. Neurosci. 26 (10), 2342-2355 (2014).</li><li>Turriziani, P., Smirni, D., Oliveri, M., Semenza, C., Cipolotti, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+the+prefrontal+cortex+in+familiarity+and+recollection+processes+during+verbal+and+non-verbal+recognition+memory.">The role of the prefrontal cortex in familiarity and recollection processes during verbal and non-verbal recognition memory.</a> Neuroimage. 52 (1), 469-480 (2008).</li><li>Tsao, D. Y., Schweers, N., Moeller, S., Freiwald, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patches+of+faces-selective+cortex+in+the+macaque+frontal+lobe.">Patches of faces-selective cortex in the macaque frontal lobe.</a> Nat. Neurosci. 11 (8), 877-879 (2008).</li></ol>

Uma abordagem abrangente para o estudo do fluxo dorsal requer uma cuidadosa seleção de tarefas comportamentais e testes visuais: visuais e preensão paradigmas podem ser empregadas ou combinados ou separadamente, dependendo das propriedades específicas da região.
Neste artigo, nós fornecemos os exemplos da atividade neural gravado em AIP e F5p em resposta a um subconjunto de tarefas visuais e motoras, mas respostas muito semelhantes podem ser observadas em outras áreas frontais como áre...

Primatas humanos e não humanos compartilham a capacidade de realizar ações complexas motor, incluindo o objeto agarrando. Para com êxito executar essas tarefas, nosso cérebro precisa para completar a transformação das propriedades do objeto intrínseco em comandos de motor. Essa transformação depende de uma sofisticada rede de áreas corticais dorsais localizado no parietal e ventral cortéx pré-motor1,2,3 (Figura 1).
De estudos de lesão em macacos e humanos4,5, sabemos que o fluxo visual dorsal - originárias do córtex visual primário e direcionada para o córtex parietal posterior - está envolvido na visão espacial e o planejamento do motor ações. No entanto, a maioria das áreas de fluxo dorsal não é dedicada a um único tipo de processamento. Por exemplo, a área intraparietal anterior (AIP), dentre as áreas de estágio final no fluxo dorsal visual, contém uma variedade de neurônios que disparam não só durante a preensão de7,6,8, mas também durante o visual inspeção do objeto7,8,9,10.
Semelhante ao AIP, neurônios na área F5, localizado no córtex cortéx ventral (PMv), também respondem durante a fixação visual e o objeto agarrando, que é provável que seja importante para a transformação da informação visual em ações motor11. A porção anterior da região (subsector F5a) contém neurônios responder seletivamente a tridimensional (3D, disparidade definida) imagens de12,13, enquanto o subsector localizado da convexidade (F5c) contém neurônios caracteriza-se pelo espelho propriedades1,3, disparando tanto quando um animal realiza ou observa uma ação. Finalmente, a região posterior do F5 (F5p) é um campo relacionado a mão, com uma alta proporção de visuomotoras neurônios responsivos à observação tanto e preensão de objetos 3D14,15. Ao lado de F5, área 45B, localizado no ramo inferior do sulco arqueado, também podem estar envolvidos em forma processamento16,17 e18de preensão.
Testes de seletividade de objeto no córtex frontal e parietal é um desafio, porque é difícil determinar o que caracteriza estes neurônios respondem e quais são os campos receptivos destes neurônios. Por exemplo, se um neurônio responde a uma placa, mas não para um cone, cuja característica desses objetos está dirigindo esta seletividade: o contorno 2D, a estrutura 3D, a orientação em profundidade ou uma combinação de muitas características diferentes? Para determinar as características do objeto de crítica para os neurônios que respondem durante a fixação do objeto e de agarramento, é necessário empregar vários testes visuais usando versões reduzidas das mesmas imagens e imagens de objetos.
Uma fração considerável dos neurônios no AIP e F5 não só responde à apresentação visual de um objeto, mas também quando o animal apreende este objeto no escuro (ou seja, na ausência de informação visual). Tais neurônios podem não responder a uma imagem de um objeto que não pode ser aproveitada. Daí, visuais e motor componentes da resposta estão intimamente ligados, que torna difícil investigar a representação do objeto neuronal nestas regiões. Desde que os neurônios visuomotoras somente podem ser testados com objetos do mundo real, precisamos de um sistema flexível para apresentar diferentes objetos em diferentes posições no campo visual e às diferentes orientações se queremos determinar quais recursos são importantes para estes neurônios. Este último só pode ser alcançado por meio de um robô capaz de apresentar objetos diferentes em locais diferentes no espaço visual.
Este artigo pretende fornecer um guia experimental para pesquisadores interessados no estudo dos neurônios parieto-frontal. Nas seções seguintes, nós forneceremos o protocolo geral utilizado em nosso laboratório para a análise das respostas de preensão e visual objeto em macacos acordado (Macaca mulatta).

<table>
	<tbody>
		<tr>
			<td>Grasping robot</td>
			<td>GIBAS Universal Robots</td>
			<td>UR-6-85-5-A</td>
			<td>Robot arm equipped with a gripper</td>
		</tr>
		<tr>
			<td>Carousel motor</td>
			<td>Siboni</td>
			<td>RD066/&#8224;20 MV6, 35x23 F02</td>
			<td>Motor to be implemented in a custom-made vertical carousel. It allows the rotation of the carousel.</td>
		</tr>
		<tr>
			<td>Eye tracker</td>
			<td>SR Research</td>
			<td>EyeLink II</td>
			<td>Infrared camera system sampling at 500 Hz</td>
		</tr>
		<tr>
			<td>Filter</td>
			<td>Wavetek Rockland</td>
			<td>852</td>
			<td>Electronic filters perform a variety of signal-processing functions with the purpose of removing a signal&#39;s unwanted frequency components.</td>
		</tr>
		<tr>
			<td>Preamplifier</td>
			<td>BAK ELECTRONICS, INC.</td>
			<td>A-1</td>
			<td>The Model A-1 allows to reduce input capacity and noise pickup and allows to test impedance for metal micro-electrodes</td>
		</tr>
		<tr>
			<td>Electrodes</td>
			<td>FHC</td>
			<td>UEWLEESE*N4G</td>
			<td>Metal microelectrodes (* = Impedance, to be chosen by the researcher)</td>
		</tr>
		<tr>
			<td>CRT monitor</td>
			<td>Vision Research Graphics</td>
			<td>M21L-67S01</td>
			<td>The CRT monitor is equipped with a fast-decay P46-phosphor operating at 120 Hz</td>
		</tr>
		<tr>
			<td>Ferroelectric liquid crystal shutters</td>
			<td>Display Tech</td>
			<td>FLC Shutter Panel; LV2500P-OEM</td>
			<td>The shutters operate at 60 Hz in front of the monkeys and are synchronized to the vertical retrace of the monitor</td>
		</tr>
	</tbody>
</table>

investigating object representations in the macaque dorsal visual stream using single-unit recordings

Estudos anteriores mostraram que os neurônios em áreas parieto-frontal do cérebro do macaco podem ser altamente seletivos para objetos do mundo real, superfícies curvas definidas pelo disparidade e imagens de objetos do mundo real (com e sem disparidade) em uma maneira similar como descrito no fluxo ventral visual. Além disso, áreas parieto-frontal são acreditadas para converter informações de objeto visual em saídas de motor adequadas, tais como o pré-moldar da mão durante a preensão. Para melhor caracterizar a seletividade de objeto na rede cortical envolvida nas transformações visuomotoras, nós fornecemos uma bateria de testes destinados a analisar a seletividade de objeto visual de neurônios em regiões parieto-frontal.

Figura 5 parcelas as respostas de um neurônio exemplo gravado de área F5p testado com quatro objetos: duas diferentes formas - uma esfera e uma placa-mostrada em dois tamanhos diferentes (6 e 3 cm). Este neurônio particular respondeu não só à esfera grande (estímulo ideal; painel esquerdo superior), mas também para o prato grande (painel inferior esquerdo). Em comparação, a resposta para os objetos menores era mais fraca (superior e inferior direito...

Watch this Scientific Journal Video about Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings at JoVE.com

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

É apresentado um protocolo detalhado para analisar a seletividade de objeto de parieto-frontal neurônios envolvidos nas transformações visuomotoras.

Investigar as representações do objeto no fluxo Dorsal de Visual de Macaque usando gravações unitárias

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

This method can help answering key questions in visual and motor systems neuroscience. For example, how do neurons encode objects and and object parts? And how do neural representations change from visual to motor?The main advantage of this method is that neurons can be studied with real-world objects during reaching and grasping, and with images of objects and object parts presented on a display. Demonstrating this procedure will be Maria Romero, a postdoc, and Irene Caprara, a PhD student from my laboratory. Begin with the test subject situated in the testing chair in front of the object-grasping setup.Adjust an infrared camera in front of the subject's eyes to obtain an adequate image of the pupil and corneal reflex. To run the visually-guided grasping task using a carousel setup, first allow the macaque to place the hand contralateral to the recorded hemisphere in the resting position in complete darkness to initiate the sequence. After a variable intertrial interval of 2, 000 to 3, 000 milliseconds, apply a red laser as a fixation point at the base of the object.If the animal maintains its gaze inside an electronically-defined fixation window for 500 milliseconds, illuminate the object from above with a light source. Then, after a variable delay of 300 to 1, 500 milliseconds, program a dimming of the laser as the visual go cue. Instruct the macaque to lift the hand from the resting position and reach, grasp, and hold the object for a randomized variable interval of 300 to 900 milliseconds.Whenever the macaque performs the whole sequence correctly, reward it with a drop of juice. As for the carousel setup, let the macaque place the hand contralateral to the recorded hemisphere in the resting position in complete darkness to initiate the sequence. After 2, 000 to 3, 000 milliseconds, illuminate the LED on the object.Again, if the animal maintains its gaze inside an electronically-defined fixation window, illuminate the object with a white light source. After the delay, switch off the LED as the visual go cue. Again, the monkey lifts the hand from the resting position and reaches, grasps, and holds the object.Reward the monkey with a drop of juice after each correct sequence. Continue the training with additional objects. During the task, the software should measure the reaction time between the go signal and the onset of the hand movement.And the grasping time between the start of the movement and lifting of the object. For the 2D tasks, use a standard LCD monitor. Project all visual stimuli on a black background.For the 3D tests, locate two ferroelectric liquid crystal shutters in front of the monkey's eyes. For the 3D test, locate two ferroelectric liquid crystal shutters in front of the monkey's eyes. Present the stimuli stereoscopically by alternating the left and right eye images on a cathode ray tube monitor equipped with a fast-decay P46 phosphor, while operating the shutters at 60 hertz with synchronization to the vertical retrace of the monitor.Start the trial by presenting a small square in the center of the screen as the fixation point. If the eye position remains within an electronically-defined one-degree-square window for at least 500 milliseconds, present the visual stimulus on the screen for a total time of 500 milliseconds. When the monkey maintains a stable fixation until the stimulus offset, reward it with a drop of juice.To study shape selectivity, run multiple tests with 2D images during the passive fixation task beginning with a search test. Test the visual selectivity of the cell using a wide set of images, including pictures of the object that was grasped in the VGG. For this and all subsequent visual tasks, compare the image evoking the strongest response, termed preferred image, to a second image to which the neuron is responding weakly, termed nonpreferred image.Next, run a contour test. From the original surface images of real objects, obtain progressively simplified versions of the same stimulus shape. Collect at least 10 trials per condition.To determine whether the neuron prefers the original surface, the silhouette, or the outline from the original shape. Then run a receptive field test. Present the images of objects at different positions on a display, covering the central visual field.A total of 35 positions at three degrees are used here. Finally, run a reduction test with contour fragments presented at the center of the receptive field to identify the minimum effective shape feature. Determine the minimum effective shape feature as the smallest shape fragment evoking a response that is at least 70%of the intact outline response.This image shows the responses of an example neuron recorded from area F5p, tested with a sphere and a plate, shown in two different sizes. This particular neuron responded not only to the large sphere optimal stimulus, but also to the large plate. In comparison, the response to the smaller objects was weaker.The following images show results from an example neuron recorded in the anterior intraparietal area, and tested during both the visually-guided grasping task and passive fixation. This neuron was responsive during grasping. The neuron was also responsive to the visual presentation of 2D images of objects, including pictures of the objects used in the grasping task.The preferred was not the object to be grasped, but another 2D picture with which the animal had no previous grasping experience. An example of the responses obtained in the reduction test is shown here. This example neuron responded to the smallest fragments in the test.Once mastered, this technique can be done in less than 90 minutes, if it's performed correctly. After watching this video, you should have a good understanding of how to test neurons in the dorsal visual stream with objects and images of objects to determine the critical features that drive the responses.

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Única unidade de In vivo Gravações do quiasma óptico de rato

Information about the visual world is transmitted to the brain in sequences of action potentials in retinal ganglion cell axons that make up the optic ...

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Transretinal ERG Recordings from Mouse Retina: Rod and Cone Photoresponses

Transretinal Recordings ERG de Retina do mouse: Rod e Photoresponses Cone

There are two distinct classes of image-forming photoreceptors in the vertebrate retina: rods and cones. Rods are able to detect single photons of light ...

Retrograde Fluorescent Labeling Allows for Targeted Extracellular Single-unit Recording from Identified Neurons In vivo

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Labeling fluorescentes retrógrada Permite alvejado Extracelular Gravação Single-unidade dos neurônios identificados<em&gt; In vivo</em

The overall goal of this method is to record single-unit responses from an identified population of neurons. In vivo electrophysiological recordings from ...

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

Dois registros eletrofisiológicos de sinapticamente evocadas Respostas astroglial e neuronal em fatias hipocampais agudas

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

Simultaneous Whole-cell Recordings from Photoreceptors and Second-order Neurons in an Amphibian Retinal Slice Preparation

Gravações Whole-cell simultâneas de fotorreceptores e os neurônios de segunda ordem em um anfíbio Retinal Slice Preparação

One of the central tasks in retinal neuroscience  is to understand the circuitry of retinal neurons and how those connections are  responsible for shaping ...

A Procedure for Implanting Organized Arrays of Microwires for Single-unit Recordings in Awake, Behaving Animals

Um Procedimento para Implantação de Arrays organizado de microfios para gravações a única unidade em Awake, comportando-se Animais

In vivo electrophysiological recordings in the awake, behaving animal provide a powerful method for understanding neural signaling at the single-cell ...

A Guide to In vivo Single-unit Recording from Optogenetically Identified Cortical Inhibitory Interneurons

A Guide to In vivo Single-unit Recording from Optogenetically Identified Cortical Inhibitory Interneurons

Um Guia para<em&gt; In vivo</em&gt; Gravação única unidade de Optogenetically Identificado Cortical Inibitória Interneurônios

A major challenge in neurophysiology has been to characterize the response properties and function of the numerous inhibitory cell types in the cerebral ...

Simultaneous ex vivo Functional Testing of Two Retinas by in vivo Electroretinogram System

Simultaneous ex vivo Functional Testing of Two Retinas by in vivo Electroretinogram System

Simultâneo<em&gt; Ex vivo</em&gt; Teste Funcional de Dois retinas por<em&gt; In vivo</em&gt; Sistema Eletrorretinograma

An In vivo electroretinogram (ERG) signal is composed of several overlapping components originating from different retinal cell types, as well as noise ...

In Vitro Modeling of Cancerous Neural Invasion: The Dorsal Root Ganglion Model

In Vitro Modeling of Cancerous Neural Invasion: The Dorsal Root Ganglion Model

In Vitro Modelagem de Cancerous Neural Invasion: o gânglio Modelo de raiz dorsal

One way that solid tumors disseminate is through neural invasion. This route is well-known in cancers of the head and neck, prostate, and pancreas. These ...

Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography

Medição Conectividade no Visual principal via de albinismo humano utilizando tensor de difusão e tractography

In albinism, the number of ipsilaterally projecting retinal ganglion cells (RGCs) is significantly reduced. The retina and optic chiasm have been proposed ...