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 takker Inez Puttemans, Marc De Paep, Sara De Pril, Wouter Depuydt, Astrid Hermans, Piet Kayenbergh, Gerrit Meulemans, Christophe Ulens og Stijn Verstraeten for teknisk og administrativ bistand.

Alle tekniske procedurer blev udført i overensstemmelse med National Institute of Health's Guide til pleje og anvendelse af forsøgsdyr og EU direktiv 2010/63/EU og blev godkendt af det etiske udvalg af KU Leuven.
1. generelle metoder til ekstracellulære optagelser i vågen opfører sig aber
<ol><li>Træne dyrene til at udføre de visuelle og motoriske opgaver, der kræves for at håndtere din specifikke forskningsspørgsmål. Sikre, at dyret er i stand til fleksibelt skifte mellem opgaver...

<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. 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. 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En omfattende tilgang til studiet af den dorsale stream kræver en omhyggelig udvælgelse af adfærdsmæssige opgaver og visuelle tests: visuelle og grådige paradigmer kan være ansat enten samlet eller særskilt afhængigt af de specifikke egenskaber af regionen.
I denne artikel, vi giver eksempler på den neurale aktivitet registreret i både AIP og F5p som svar på en delmængde af visuelle og motoriske opgaver, men meget lignende svar kan observeres i andre frontal områder som området 4...

Menneskelige og ikke-menneskelige primater del kapacitet til at udføre komplekse motor handlinger herunder objekt grådige. For at kunne udføre disse opgaver, vores hjerne har brug at fuldføre omdannelsen af iboende objektegenskaber til motoriske kommandoer. Denne transformation er afhængig af en sofistikeret netværk af dorsale kortikale områder beliggende i parietal og ventrale premotor cortex1,2,3 (figur 1).
Vi ved fra læsion undersøgelser i aber og mennesker4,5, at den dorsale visuelle stream - med oprindelse i primære visuelle cortex og rettet mod posterior parietal cortex - er involveret i både rumlig vision og planlægning af motor handlinger. Imidlertid er størstedelen af dorsale stream områder ikke helliget en unik form for forarbejdning. For eksempel, indeholder den forreste intraparietal område (AIP), en af slutningen fase områder i den dorsale visuelle stream, en bred vifte af neuroner, der ild under fatte6,7,8, men også under visuelle inspektion af objektet7,8,9,10.
Svarende til AIP, neuroner i området F5, beliggende i den ventrale premotor cortex (PMv), også reagere i løbet af visuelle fiksering og objekt grådige, som sandsynligvis vil være vigtigt for omdannelsen af visuel information til motor handlinger11. Den forreste del af denne region (delsektoren F5a) indeholder neuroner reagerer selektivt på tre-dimensionelle (3D, ulighed-defineret) billeder12,13, mens delsektoren beliggende i Konveksitet (F5c) indeholder neuroner karakteriseret ved spejl egenskaber1,3, fyring både når et dyr udfører eller bemærker en handling. Endelig, den posteriore F5 region (F5p) er en hånd-relaterede felt, med en høj andel af visuomotor neuroner lydhøre over for både observation og fatte af 3D objekter14,15. Ved siden af F5, område 45B, beliggende i den ringere ramus af arcuate sulcus, kan også være involveret i både form forarbejdning16,17 og grådige18.
Test objekt selektivitet i parietal og frontale cortex udfordrende, fordi det er vanskeligt at afgøre hvilke funktioner disse neuroner reagerer på og hvad de receptive felter af disse neuroner er. For eksempel, hvis et neuron svarer til en plade, men ikke til en kegle, som funktion af disse objekter er drivkraften bag denne selektivitet: 2D konturen, 3D-struktur, orientering i dybden, eller en kombination af mange forskellige funktioner? For at fastslå de kritiske objekt funktioner for neuroner, der reagerer under objekt fiksering og grådige, er det nødvendigt at ansætte forskellige visuelle test ved hjælp af billeder af objekter og reduceret versioner af de samme billeder.
En betydelig brøkdel af neuroner i AIP og F5 ikke kun reagerer på den visuelle præsentation af et objekt, men også når dyret griber dette objekt i mørke (dvs. i mangel af visuel information). Sådanne neuroner kan ikke reagere på et billede af et objekt, der ikke kan udnyttes. Derfor, visuelle og motor komponenter af reaktionen er tæt forbundet, hvilket gør det vanskeligt at undersøge neuronal objekt repræsentation i disse regioner. Da visuomotor neuroner kan kun testes med virkelige verden objekter, vi har brug for et fleksibelt system for at præsentere forskellige objekter på forskellige positioner i det visuelle felt og forskellige orienteringer, hvis vi ønsker at bestemme, hvilke funktioner der er vigtigt for disse neuroner. Sidstnævnte kan kun opnås ved hjælp af en robot i stand til at præsentere forskellige objekter på forskellige steder i visuelle rum.
Denne artikel har til hensigt at give en eksperimentel guide for forskere interesseret i studiet af parieto-frontal neuroner. I de følgende afsnit, vil vi give den generelle protokol, der bruges i vores laboratorium for analysen af grådige og visuelle objekt svar i vågen makak aber (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

Tidligere undersøgelser har vist, at neuroner i parieto-frontal områder af hjernen, makak kan være yderst selektiv for virkelige verden objekter, ulighed-defineret buede overflader og billeder af virkelige verden objekter (med og uden forskel) på samme måde som beskrevet i den ventrale visuelle stream. Derudover menes parieto-frontal områder at konvertere visual objektoplysninger i passende motor udgange, såsom pre udformningen af hånden under greb. For at bedre karakterisere objekt selektivitet i det kortikale netværk involveret i visuomotor transformationer, giver vi et batteri af tests til formål at analysere visuelt objekt selektivitet af neuroner i parieto-frontal regioner.

Figur 5 grunde svarene fra en eksempel neuron optaget fra området F5p testet med fire genstande: to forskellige figurer - en kugle og en plade-vist i to forskellige størrelser (6 og 3 cm). Denne særlige neuron reagerede ikke kun til den store kugle (optimal stimulus, øverste venstre panel), men også til den store plade (nederste venstre panel). I sammenligning, svar på de mindre objekter blev svagere (øvre og nedre højre paneler).
<p class="jove_c...

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

En detaljeret protokol til at analysere objekt selektivitet parieto-frontal neuroner involveret i visuomotor transformationer er præsenteret.

Undersøge objekt repræsentationer i makak dorsale Visual strøm ved hjælp af Single-enhed optagelser

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

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