The authors would like to thank Bernardo Luiz for technical assistance with filming and editing. This work was supported by Santos Dumont Institute (ISD), Brazilian Ministry of Education (MEC) and Coordena&#231;&#227;o de Aperfei&#231;oamento de Pessoal de N&#237;vel Superior (CAPES).

Animal experiments were performed in accordance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals and approved by the Santos Dumont Institute Ethics Committee (protocol 02/2015AAS).
1. Surgery preparation
<ol>
	<li>Attach each electrode array to an electrode holder compatible with the stereotaxic frame to be used.</li>
	<li>Connect one electrode holder to the stereotaxic micromanipulator and set one microwire to the interaural coordinates. Repeat this fo...

<ol>
	<li>Okano, H., Hikishima, K., Iriki, A., Sasaki, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+common+marmoset+as+a+novel+animal+model+system+for+biomedical+and+neuroscience+research+applications.">The common marmoset as a novel animal model system for biomedical and neuroscience research applications.</a> Seminars in Fetal and Neonatal Medicine. 17 (6), 336-340 (2012).</li><li>Harris, R. A., 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=Evolutionary+genetics+and+implications+of+small+size+and+twinning+in+callitrichine+primates.">Evolutionary genetics and implications of small size and twinning in callitrichine primates.</a> Proceedings of the National Academy of Sciences. 111 (4), 1467-1472 (2014).</li><li>Kishi, N., Sato, K., Sasaki, E., Okano, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Common+marmoset+as+a+new+model+animal+for+neuroscience+research+and+genome+editing+technology.">Common marmoset as a new model animal for neuroscience research and genome editing technology.</a> Development, Growth &amp; Differentiation. 56 (1), 53-62 (2014).</li><li>Sasaki, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prospects+for+genetically+modified+non-human+primate+models,+including+the+common+marmoset.">Prospects for genetically modified non-human primate models, including the common marmoset.</a> Neuroscience Research. 93, 110-115 (2015).</li><li>Sasaki, E., 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=Generation+of+transgenic+non-human+primates+with+germline+transmission.">Generation of transgenic non-human primates with germline transmission.</a> Nature. 459 (7246), 523-527 (2009).</li><li>Sasaki, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Creating+Genetically+Modified+Marmosets.">Creating Genetically Modified Marmosets.</a> The Common Marmoset in Captivity and Biomedical Research. , 335-353 (2019).</li><li>Sato, 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=Generation+of+a+Nonhuman+Primate+Model+of+Severe+Combined+Immunodeficiency+Using+Highly+Efficient+Genome+Editing.">Generation of a Nonhuman Primate Model of Severe Combined Immunodeficiency Using Highly Efficient Genome Editing.</a> Cell Stem Cell. 19 (1), 127-138 (2016).</li><li>Sato, 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=Resequencing+of+the+common+marmoset+genome+improves+genome+assemblies+and+gene-coding+sequence+analysis.">Resequencing of the common marmoset genome improves genome assemblies and gene-coding sequence analysis.</a> Scientific Reports. 5, 16894 (2015).</li><li>Chaplin, T. A., Yu, H. H., Soares, J. G. M., Gattass, R., Rosa, M. G. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Conserved+Pattern+of+Differential+Expansion+of+Cortical+Areas+in+Simian+Primates.">A Conserved Pattern of Differential Expansion of Cortical Areas in Simian Primates.</a> Journal of Neuroscience. 33 (38), 15120-15125 (2013).</li><li>Mitchell, J. F., Leopold, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+marmoset+monkey+as+a+model+for+visual+neuroscience.">The marmoset monkey as a model for visual neuroscience.</a> Neuroscience Research. 93, 20-46 (2015).</li><li>Brok, H. P. 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D., Barker, K., Schaeffer, L., Schaeffer, D., Everling, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+for+chair+restraint+and+training+of+the+common+marmoset+on+oculomotor+tasks.">Methods for chair restraint and training of the common marmoset on oculomotor tasks.</a> Journal of Neurophysiology. 119 (5), 1636-1646 (2018).</li><li>Sedaghat-Nejad, E., 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=Behavioral+training+of+marmosets+and+electrophysiological+recording+from+the+cerebellum.">Behavioral training of marmosets and electrophysiological recording from the cerebellum.</a> Journal of Neurophysiology. , (2019).</li><li>Kringelbach, M. L., Owen, S. L., Aziz, T. Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deep-brain+stimulation.">Deep-brain stimulation.</a> Future Neurology. 2 (6), 633-646 (2007).</li><li>Talakoub, O., Gomez Palacio Schjetnan, A., Valiante, T. A., Popovic, M. R., Hoffman, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Closed-Loop+Interruption+of+Hippocampal+Ripples+through+Fornix+Stimulation+in+the+Non-Human+Primate.">Closed-Loop Interruption of Hippocampal Ripples through Fornix Stimulation in the Non-Human Primate.</a> Brain Stimulation. 9 (6), 911-918 (2016).</li><li>Oddo, M., Hutchinson, P. 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M., Deisseroth, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+Deconstruction+of+Parkinsonian+Neural+Circuitry.">Optical Deconstruction of Parkinsonian Neural Circuitry.</a> Science. 324, 354-359 (2009).</li><li>Hammer, D. X., 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=Longitudinal+vascular+dynamics+following+cranial+window+and+electrode+implantation+measured+with+speckle+variance+optical+coherence+angiography.">Longitudinal vascular dynamics following cranial window and electrode implantation measured with speckle variance optical coherence angiography.</a> Biomedical Optics Express. 5 (8), 2823-2836 (2014).</li><li>Komatsu, M., Kaneko, T., Okano, H., Ichinohe, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+Implantation+of+Whole-cortical+Electrocorticographic+Array+in+the+Common+Marmoset.">Chronic Implantation of Whole-cortical Electrocorticographic Array in the Common Marmoset.</a> Journal of Visualized Experiments. (144), (2019).</li><li>Oliveira, L. M. O., Dimitrov, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Surgical Techniques for Chronic Implantation of Microwire Arrays in Rodents and Primates. , (2008).</li><li>Santana, M. B., 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=Spinal+Cord+Stimulation+Alleviates+Motor+Deficits+in+a+Primate+Model+of+Parkinson's+disease.">Spinal Cord Stimulation Alleviates Motor Deficits in a Primate Model of Parkinson's disease.</a> Neuron. 84 (4), 716-722 (2014).</li><li>Santana, M., Palm&#233;r, T., Simpl&#237;cio, H., Fuentes, R., Petersson, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+long-term+motor+deficits+in+the+6-OHDA+model+of+Parkinson's+disease+in+the+common+marmoset.">Characterization of long-term motor deficits in the 6-OHDA model of Parkinson's disease in the common marmoset.</a> Behavioural Brain Research. 290, 90-101 (2015).</li><li>Misra, S., Koshy, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+the+practice+of+sedation+with+inhalational+anaesthetics+in+the+intensive+care+unit+with+the+AnaConDa+device.">A review of the practice of sedation with inhalational anaesthetics in the intensive care unit with the AnaConDa device.</a> Indian Journal of Anaesthesia. 56 (6), 518-523 (2012).</li><li>Freire, M. 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The authors have nothing to disclose.

This work provides a detailed description of the procedures involved in the implantation of microelectrode recording arrays in the marmoset brain. This same protocol can be readily used when implanting electrodes, whether homemade or commercially available, in other small primates. Additionally, it can be easily adapted for other experimental ends that require precise targeting of brain structures. Therefore, this protocol is purposefully vague regarding stereotaxic coordinates and cranial drilling techniques, because th...

Common marmosets (Callithrix jacchus) are gaining recognition as an important model organism in many fields of research, including neuroscience. These new-world primates represent an important complementary animal model to both rodents and other non-human primates (NHPs), such as the rhesus macaque. Like rodents, these animals are small, easy to manipulate, and relatively economical to care for and breed1,2,3,4, as compared with larger NHPs. Furthermore, these animals have a propensity for twinning and high fecundity relative to other NHPs1,2,3. Another advantage the marmoset has over many other primates is that modern molecular biology tools3,4,5,6,7 and a sequenced genome2,3,4,5,8 have been used to genetically modify them. Both knock-in animals using lentivirus5, and knock-out animals using zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENS)7, have yielded viable founder animals.
An advantage in relation to rodents is that marmosets, as primates, are phylogenetically closer to humans3,5,6,9,10,11. Like humans, marmosets are diurnal animals that depend on a highly developed visual system to guide much of their behavior10. Further, marmosets exhibit behavioral complexity, including a wide range of social behaviors such as the use of different vocalizations3, allowing researchers to address questions not possible in other species. From a neuroscientific perspective, marmosets have lissencephaly brains, unlike the more commonly used rhesus macaque9. Furthermore, marmosets have a central nervous system similar to humans, including a more highly developed prefrontal cortex9. Together, all these characteristics position marmosets as a valuable model to study brain function in health and disease.
A common method for studying brain function involves implanting electrodes in anatomically specific locations by means of stereotaxic neurosurgery. This allows for chronical recording of the neural activity in different target areas in awake and freely behaving animals12,13. Stereotaxic neurosurgery is an indispensable technique used in many lines of research, as it allows precise targeting of neuroanatomical regions. Compared to macaque and rodent literature, there are fewer published studies describing the stereotaxic neurosurgery specific to the marmoset, and they tend to provide sparse detail of the steps involved in the surgery. Moreover, those with greater detail mainly focus on procedures for electrophysiology recording in head-restrained animals14,15,16,17.
In order to facilitate wider adoption of marmosets as a model organism in neuroscience research, the present method defines specific steps necessary for a successful stereotaxic neurosurgery in this species. In addition to implantation of recording arrays, as detailed in the present method, the same technique can be adapted for many other experimental ends, including implantation of stimulating electrodes for the treatment of diseases18 or causally driving circuit behavior19; implantation of guide cannulas for extraction and quantification of neurotransmitters20, injections of reagents, including those for inducing disease models12 or for circuit tracing studies15; ablation of discrete tissue regions21; implantation of optrodes for optogenetic studies22; implantation of optical windows for cortical microscopic analysis23; and implantation of electrocorticographic (ECoG) arrays24. Thus, the overall goal of this procedure is to outline the surgical steps involved in the implantation of microelectrode arrays for chronic electrophysiological recordings in freely behaving marmosets.

<table>
	<tbody>
		<tr>
			<td>Equipments</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>683 Small Animal Ventilator</td>
			<td>Harvard Apparatus, Inc.</td>
			<td>55-0000</td>
			<td></td>
		</tr>
		<tr>
			<td>Anesthesia Assembly</td>
			<td>BRASMED</td>
			<td>COLIBRI</td>
			<td></td>
		</tr>
		<tr>
			<td>Barber Clippers</td>
			<td>Mundial</td>
			<td>HC-SERIES</td>
			<td></td>
		</tr>
		<tr>
			<td>Dental Drill</td>
			<td>Norgen</td>
			<td>B07-201-M1KG</td>
			<td></td>
		</tr>
		<tr>
			<td>Homeothermic Heating Pad and Monitor</td>
			<td>Harvard Apparatus, Inc.</td>
			<td>50-7212</td>
			<td></td>
		</tr>
		<tr>
			<td>Marmoset Stereotaxic Frame</td>
			<td>Narishige Scientific Instrument Lab</td>
			<td>SR-6C-HT</td>
			<td></td>
		</tr>
		<tr>
			<td>Patient Monitor and Pulse Oximeter</td>
			<td>Bionet Co., Ltd</td>
			<td>BM3</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereotaxic Micromanipulator</td>
			<td>Narishige Scientific Instrument Lab</td>
			<td>SM-15R</td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical Microscope</td>
			<td>Opto</td>
			<td>SM PLUS IBZ</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Instruments</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Allis tissue forceps</td>
			<td>Sklar</td>
			<td>36-2275</td>
			<td></td>
		</tr>
		<tr>
			<td>Alm Retractor, rounded point, 4x4 teeth</td>
			<td>Rhosse</td>
			<td>RH11078</td>
			<td></td>
		</tr>
		<tr>
			<td>Angled McPherson Forceps</td>
			<td>Oftalmologiabr</td>
			<td>11301A</td>
			<td></td>
		</tr>
		<tr>
			<td>Curved Surgial Scissors</td>
			<td>Harvard Apparatus, Inc.</td>
			<td>72-8422</td>
			<td></td>
		</tr>
		<tr>
			<td>Curved Tissue Forceps</td>
			<td>Sklar</td>
			<td>47-1186</td>
			<td></td>
		</tr>
		<tr>
			<td>Delicate Dissection forceps</td>
			<td>WPI</td>
			<td>WP5015</td>
			<td></td>
		</tr>
		<tr>
			<td>Dental Drill Bit</td>
			<td>Microdont</td>
			<td>ISO.806.314.001.524.010</td>
			<td></td>
		</tr>
		<tr>
			<td>Essring Tissue Forceps</td>
			<td>Sklar</td>
			<td>19-2460</td>
			<td></td>
		</tr>
		<tr>
			<td>FG 1/4 Dental Drill Bit</td>
			<td>Microdont</td>
			<td>ISO.700.314.001.006.005</td>
			<td></td>
		</tr>
		<tr>
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stereotaxic surgery for implantation of microelectrode arrays in the common marmoset (callithrix jacchus)

Marmosets (Callithrix jacchus) are small non-human primates that are gaining popularity in biomedical and preclinical research, including the neurosciences. Phylogenetically, these animals are much closer to humans than rodents. They also display complex behaviors, including a wide range of vocalizations and social interactions. Here, an effective stereotaxic neurosurgical procedure for implantation of recording electrode arrays in the common marmoset is described. This protocol also details the pre- and postoperative steps of animal care that are required to successfully perform such a surgery. Finally, this protocol shows an example of local field potential and spike activity recordings in a freely behaving marmoset 1 week after the surgical procedure. Overall, this method provides an opportunity to study the brain function in awake and freely behaving marmosets. The same protocol can be readily used by researchers working with other small primates. In addition, it can be easily modified to allow other studies requiring implants, such as stimulating electrodes, microinjections, implantation of optrodes or guide cannulas, or ablation of discrete tissue regions.

The purpose of this study was to describe a stereotaxic neurosurgical procedure for implantation of microelectrode arrays for electrophysiological recordings in the common marmoset. A typical surgery (from anesthesia induction to anesthesia recovery) will last for approximately 5&#8722;7 h, depending on the number of arrays implanted. Here, two arrays were symmetrically implanted, one in each brain hemisphere. Each array contained 32 stainless steel microwires arranged in seven bundles targeting several structures of the...

Watch this Scientific Journal Video about Stereotaxic Surgery for Implantation of Microelectrode Arrays in the Common Marmoset Callithrix jacchus at JoVE.com

Stereotaxic Surgery for Implantation of Microelectrode Arrays in the Common Marmoset Callithrix jacchus

This work presents a protocol to perform a stereotaxic, neurosurgical implantation of&#160;microelectrode arrays in the common marmoset. This method specifically enables electrophysiological recordings in freely behaving animals but can be easily adapted to any other similar neurosurgical intervention in this species (e.g., cannula for drug administration or electrodes for brain stimulation).

Stereotaxic Surgery for Implantation of Microelectrode Arrays in the Common Marmoset (Callithrix jacchus)

Marmosets (Callithrix jacchus) are small non-human primates that are gaining popularity in biomedical and preclinical research, including the ...

The overall goal of this procedure is to outline the surgical steps involved in the implantation of microelectrode arrays for chronic electrophysiologic recording in freely behaving marmosets. Marmosets are small primates that are increasingly being used in neuroscience research. These animals share many of the practical and logistical advantages of rodents.Their propensity for twinning and high fecundity at young ages means ready access to large and genetically similar cohorts. In addition, their small body size makes them easy and relatively cheap to care for. As primates, the marmoset has a central nervous system that is much more similar to a human than that of a rodent.This includes a highly developed prefrontal cortex and visual system. An advantage that marmosets have over many other species of primates however, is the progress made in genetically modifying them. With a deeply sequenced genome and success generating founder knock-in and knock-out animals, it is clear that the marmoset is poised to become a powerful model for studying brain function in health and disease.A common method for study brain function involves implanting electrodes in anatomically specific locations. This allows one to chronically record the neural activity in different target areas in awake and freely behaving animals. Prior to the surgery determine the intraoral zero coordinate for all implants and guides.To do so, attach each electrode array that will be implanted to an electrode holder and set one micro wire to the intraoral zero. This is where the ear bars meet. Repeat this for the additional electrode arrays and holders, if necessary.In addition, repeat this with a 24 gauge needle similarly attached to a stereotaxic probe holder. For electrophysiologic arrays, a ground wire should be soldered to every other screw that will be used. Finally, organize and sterilize all instruments, equipment, and disposables in preparation for the surgical procedure.On the day of the surgery insure the animal has not eaten for six hours prior to beginning anesthesia. Atropine and ketamine will be used to induce anesthesia by sequential, intramuscular injections. Next, shave the animals head using barber clippers.It is important to intubate the animal during surgery. Our preferred method involves attaching an elastic band to the surgical table which we insert behind the animals canines while it is in a supine position. We next use a cotton tipped probe to swab dry the marmoset's tongue and grasp it in one hand.This allows a technician to open the mouth and airway with only one hand. After inserting the endotracheal tube, attach it to the anesthesia assembly with the artificial ventilator set to 40 breaths per minute. Secure the tube and assembly with tape, as needed.With the marmoset now in prone position fix the animal's head into the stereotaxic frame. To do so, first, insert the tip of the right ear bar into the animal's right auditory canal. Followed by the left ear bar into the left auditory canal.Next, the head must be leveled such that the horizontal plane is parallel with the frame, while the anterior/posterior plane is centered. This is achieved by first centering the animal's head using the ear bar measurements secured at equal distances. Following this, the mouth piece is inserted into the animal's mouth, and adjusted until it touches the animal's palette, while the orbital bars are just touching the lower margin of the orbital bone.As the horizontal plane is defined as the plane passing through the lower margin of the orbital bone and the center of external auditory medius, one should make sure that the lower surface of the orbital bone is now horizontally aligned with the center of the ear bars before proceeding. During the procedure, it is important to maintain all vital signs. Thus one should connect a portable pulse oximeter to the marmoset's hand to ensure that heart rate and oxygen saturation are within the acceptable ranges.In addition a rectal temperature probe connected to a homeothermic heating pad set for 37 degrees centigrade, and taped to the tail, will ensure the marmoset's body temperature is not adversely affected by anesthesia. The final pre-operative step is to clean and disinfect the animal's shaved head with chlorhexidine and iodine, before covering the animal with a sterilized surgical field. Perform an incision in the midline of the scalp after applying a local analgesic at this site.To prepare the surface of the skull, first, carefully detach the temporal muscle from the cranium. This is done by cutting the fossa at it's insertion into the skull with a scalpel. After which, the temporal muscle should be gently separated from the cranium, using a periosteal raspatory.Continuing with the periosteal raspatory remove the periosteum from all exposed cranium by scraping. Next, mark the location of the craniotomy by creating shallow burr holes into the bone surface and drilling out the perimeter of the craniotomy. Drill six to eight screw holes, as needed, into the cranium and implant the screws.At this time, wind the ground wires soldered to a given screw around the adjacent unsoldered screw. Remove the bone at the center of the craniotomy using McPherson forceps. While the brain and dura mater are uncovered keep them hydrated with sterile saline.To remove the dura mater, a 25 or 26 gauge needle should be bent at approximately 90 degrees to facilitate puncturing and lifting the surface of the dura mater away from the brain's surface. At this point, micro scissors are used to excise the dura mater. Attach the electrodes to the stereotaxic micromanipulator and position it, such that the electrode is at the desired anterior/posterior and medial/lateral coordinates.Now, lower the tip of the electrode until it touches the surface of the brain. Slowly insert the array into the brain, until it reaches the desired dorsal/ventral coordinates. Add a drop of silver paint between the ground wire and each screw to ensure an electrical connection.Secure the electrode to the skull by applying dental acrylic to the exposed skull, one screw, and the electrode array. Repeat this implantation procedure with any additional arrays. Finally, using dental acrylic, make a sturdy head cap around the lateral extent of the arrays and completely in case the ground wires and any exposed skull or screws.If necessary, one can insert a support bar into the head cap and seal it into place with dental acrylic. Following creation of the head cap suture the skin if muscle or bone tissue is exposed. An antiseptic solution should also be applied to the wound at this time.With the surgery completed it is time to begin recovery. First, turn off the isoflurane supply, but not the oxygen, and remove the animal from the stereotaxic frame. Place the animal onto the heating page, with the oxygen maintained through the endotracheal tube.When the first sign of neurogenic reflexes such as laryngeal spasms begin, remove the endotracheal tube. Oxygen should now be supplied with a mask until the animal presents clear signs of anesthetic recovery, such as protective reflexes, postural tone, and attempts to ambulate. The marmoset should be housed individually, and left to recover in a clean cage and room for 24 to 48 hours, before returning to it's home cage.Implanted animals should be housed in separate cages. It is important to observe the animal for at least one hour following the surgery to watch for signs of distress and specifically, uncoordinated movements. Antibiotics and analgesics and antiinflammatory drugs should be administered in the days following surgery to control pain and prevent infection.In successful surgeries, the animal should be completely recovered within three to five days. We recommend electrophysiologic recording sessions begin at least one week after the surgery. At the beginning of each recording session lightly anesthetize the animal using isoflurane and connect the electrode arrays connector to a neural recording system.Place the animal inside the experimental chamber and wait for full anesthetic recovery before beginning the recordings. After a successful surgery, it is possible to record spikes and local field potentials from the implanted electrodes over several weeks. Ultimately a final confirmation that the electrode arrays were successfully implanted into the target structures should be preformed post-mortem.Nissl stained sections containing electro tracks can be used to determine the position of each implanted micro wire. Chronic electrophysiologic recordings in awake behaving animals are powerful techniques used in many lines of neuroscience research. As the common marmoset offers many advantages over historically popular models, the purpose of this video, is to help other neuroscientists adopt the common marmoset for their research.In addition to the implantation of chronic recording electrodes, as detailed in this video, the same stereotaxic surgery protocol can be adapted for many other experimental ends, including implantation of stimulating electrodes, guide cannulas, and microinjections. When adapting this protocol for one of the fore mentioned techniques, the surgeon will principally modify the drilling procedure to conform of the size of the desired implant. Additionally, the ground procedure is not necessary for many of these techniques and may thus be omitted.Regardless of the experimental goal, after watching this video you should have an understanding on how to successfully perform stereotaxic neurosurgery in the common marmoset.

stereotaxic-surgery-for-implantation-microelectrode-arrays-common

Research

JoVE Journal

Neuroscience

9.1K vues.  Santos Dumont Institute. L’objectif global de cette procédure est de décrire les étapes chirurgicales impliquées dans l’implantation de tableaux de microélecrodes pour l’enregistrement électrophysiologique chronique dans les marmosets se comportant librement. Les marmosets sont de petits primates qui sont de plus en plus utilisés dans la recherche en neurosciences. Ces animaux partagent bon nombre des avantages pratiques et logistiques des rongeurs.Leur propension au jumelage et à la fécondité ...