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

Vi tackar Inez Puttemans, Marc De Paep, Sara De Pril, Wouter Depuydt, Astrid Hermans, Piet Kayenbergh, Gerrit Meulemans, Christophe Ulens och Stijn Verstraeten för tekniskt och administrativt stöd.

Alla tekniska förfaranden utfördes enligt National Institute of Health's Guide för skötsel och användning av laboratoriedjur och EU-direktiv 2010/63/EU och godkändes av den etiska kommittén i KU Leuven.
1. allmänna metoder för extracellulära inspelningar i vaken beter sig apor
<ol><li>Träna djuren att utföra visuell och motorisk krävs att din specifika forskningsfrågan. Se till att djuret kan flexibelt växla mellan aktiviteter under samma inspelningssession för att testa neur...

<ol>
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C., Pani, P., 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=Coding+of+shape+features+in+the+macaque+anterior+intraparietal+area.">Coding of shape features in the macaque anterior intraparietal area.</a> J. Neurosci. 34 (11), 4006-4021 (2014).</li><li>Sakata, H., Taira, M., Kusonoki, M., Murata, A., Tanaka, Y., Tsutsui, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+coding+of+3D+features+of+objects+for+hand+action+in+the+parietal+cortex+of+the+monkey.">Neural coding of 3D features of objects for hand action in the parietal cortex of the monkey.</a> Philos. Trans. R. Soc. Lond. B. Biol. Sci. 353 (1373), 1363-1373 (1998).</li><li>Taira, M., Mine, S., Georgopoulos, A. 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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. A., Murata, A., Fogassi, L., Gallese, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+properties+of+grasping-related+neurons+in+the+ventral+premotor+area+F5+of+the+macaque+monkey.">Functional properties of grasping-related neurons in the ventral premotor area F5 of the macaque monkey.</a> J. Neurophysiol. 95 (2), 709-729 (2006).</li><li>Umilta, M. A., Brochier, T., Spinks, R. L., Lemon, R. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simultaneous+recording+of+macaque+premotor+and+primary+motor+cortex+neuronal+populations+reveals+different+functional+contributions+to+visuomotor+grasp.">Simultaneous recording of macaque premotor and primary motor cortex neuronal populations reveals different functional contributions to visuomotor grasp.</a> J. Neurophysiol. 98 (1), 488-501 (2007).</li><li>Denys, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+processing+of+visual+shape+in+the+cerebral+cortex+of+human+and+nonhuman+primates:+a+functional+magnetic+resonance+imaging+study.">The processing of visual shape in the cerebral cortex of human and nonhuman primates: a functional magnetic resonance imaging study.</a> J. 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>

En övergripande strategi för studiet av dorsala strömmen kräver ett noggrant urval av beteendemässiga uppgifter och visuella tester: visuella och gripa paradigm kan användas antingen kombinerade eller separat beroende på de specifika egenskaperna i regionen.
I denna artikel, ger vi exempel på neurala aktiviteten registreras i både AIP och F5p som svar på en delmängd av visuella och motoriska aktiviteter, men mycket lik Svaren kan observeras i andra frontala områden såsom området ...

Mänskliga och icke-mänskliga primater dela kapacitet utför komplexa motoriska åtgärder inklusive objektet greppa. För att kunna utföra dessa uppgifter, behöver vår hjärna för att slutföra omvandlingen av inneboende objektegenskaper till motoriska kommandon. Denna omvandling är beroende av ett sofistikerat nätverk av dorsala kortikala områden som ligger i parietala och ventrala premotor cortex1,2,3 (figur 1).
Från lesionen studier på apor och människor4,5vet vi att den dorsala visuella stream - med ursprung i primära syncentrum och riktad mot bakre parietala cortex - är inblandade i både rumslig vision och planering av motor åtgärder. Men ägnas majoriteten av dorsala stream områden inte åt en unik typ av bearbetning. Exempelvis innehåller det främre intraparietal området (AIP), en av områdena slutet skede i den dorsala visuella strömmen, en mängd nervceller som brand inte bara under greppa6,7,8, utan också under visuellt inspektion av objektet7,8,9,10.
Liknar AIP, nervceller i området F5, ligger i den ventrala premotor cortexen (PMv), också svara under visuell fixation och objektet greppa, som kommer vara viktiga för omvandlingen av visuell information till motoriska handlingar11. Den främre delen av denna region (undersektor F5a) innehåller neuroner svarar selektivt till tredimensionella (3D, skillnad-definierade) bilder12,13, medan undersektorn ligger i konvexitet (F5c) innehåller neuroner kännetecknas av spegel boenden1,3, skjuter båda när ett djur utför eller har påpekat en åtgärd. Regionen för bakre F5 (F5p) är slutligen ett hand-relaterade fält, med en hög andel av visuomotor nervceller lyhörda för både observation och greppa 3D objekt14,15. Bredvid F5, området 45B, beläget i den underlägsna ramus av arcuatus sulcus, kan också vara inblandade i både formen bearbetning16,17 och gripa18.
Testa objekt selektivitet i parietala och frontala cortex är utmanande, eftersom det är svårt att avgöra vilka funktioner som dessa nervceller svara på och vad de receptiva fälten av dessa nervceller är. Om en neuron svarar till en tallrik men inte till en kon, som funktion av dessa objekt till exempel driver denna selektivitet: 2D kontur, 3D-strukturen, med orientering i djup eller en kombination av många olika funktioner? För att bestämma de kritiska objekt funktionerna för nervceller som svarar under objektet fixering och greppa, är det nödvändigt att anställa olika visuella tester med bilder av föremål och minskad versioner av samma bilder.
En ansenlig del av nervceller i AIP och F5 svarar inte bara på den visuella presentationen av ett objekt, utan även när djuret griper detta objekt i mörker (dvs. i avsaknad av visuell information). Sådana nervceller kan inte svara på en bild av ett objekt som inte kan gripas. Därav, visuell och motorisk komponenterna i svaret är nära sammankopplad, vilket gör det svårt att utreda den neuronala objekt representationen i dessa regioner. Sedan visuomotor nervceller kan endast testas med verkliga objekt, behöver vi ett flexibelt system för att presentera olika objekt på olika positioner i synfältet och olika inriktningar om vi vill bestämma vilka funktioner är viktiga för dessa neuroner. Den senare kan endast uppnås med hjälp av en robot som kan presentera olika objekt på olika platser i visuella rymden.
Denna artikel avser att ge en experimentell guide för forskares studier av parieto-frontal nervceller. I följande avsnitt kommer vi ge det allmänna protokoll som används i vårt laboratorium för analys av gripande och visuella objekt svaren i vaken Makaker apor (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

Tidigare studier har visat att nervceller i parieto-frontal områden av hjärnan som makak kan vara mycket selektiv för verkliga objekt, skillnad-definierade krökta ytor och bilder av verkliga objekt (med och utan skillnad) på ett liknande sätt som beskrivs i den ventrala visuella strömmen. Dessutom tros parieto-frontal områden att konvertera information visuella objekt till lämplig motor utgångar, såsom pre utformningen av handen under greppa. För att bättre karaktärisera objekt selektivitet i kortikala nätverk involverade i visuomotor transformationer, tillhandahåller vi ett batteri av tester avsedda att analysera visuella objekt selektivitet av nervceller i parieto-frontala regioner.

Figur 5 tomter svaren från en exempel neuron inspelade från området F5p testade med fyra objekt: två olika former - en sfär och en tallrik-visas i två olika storlekar (6 och 3 cm). Detta särskilt neuron svarade inte bara till den stora sfären (optimal stimulans; övre vänstra panelen), men också till stora plattan (nedre vänstra panelen). I jämförelse, svaret på de mindre objekten var svagare (övre och nedre höger paneler).
<p class="jove_...

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

Ett detaljerat protokoll att analysera objektet selektivitet av parieto-frontal nervceller inblandade i visuomotor transformationer presenteras.

Undersöka objektet representationer i makak dorsala Visual strömmen använder Single-unit Recordings

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

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.

Research

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Neuroscience

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Single-enhet In vivo Inspelningar från Optic Chiasm av Rat

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

Bakåtsträvande Fluorescerande märkning Tillåter Riktade Extracellular Single-enhet Inspelning från identifierade nervceller<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

Dubbla Elektrofysiologiska Inspelningar av synaptiskt-framkallade astrogliala och neuronala svar i akut hippocampus skivor

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

Samtidiga Hel-Inspelningar från fotoreceptorer och andra ordningens neuron i ett Amfibie näthinnan Slice Förberedelser

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

Ett förfarande för Implantation Organized arrayer av Microwires för Single-enhet Inspelningar i Awake, uppför djur

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

En guide till<em&gt; In vivo</em&gt; Single-enhet Inspelning från Optogenetically identifierad kortikal hämmande intern

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

Samtidig<em&gt; Ex vivo</em&gt; Funktionstest av två näthinnor efter<em&gt; In vivo</em&gt; Elektroretinogram System

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

I vitro Modellering av cancer Neural Invasion: dorsala ganglion Modell

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

Mätning Connectivity i Primär Visual Pathway i Human Albinism Använda Diffusion Tensor Imaging och tractography

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