Funding for this project was provided by the National Health and Medical Research Council (NHMRC) 1046203 (BVB, AJV) and Melbourne Neuroscience Institute Fellowship (CTN).

<ol>
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The authors have no disclosures relevant to this work.

El ERG y VEP son medidas objetivas de la función visual de la retina y la corteza, respectivamente. La ventaja de la grabación simultánea es que una visión más completa de toda la vía visual se le concede. En concreto, la información complementaria a partir de su evaluación concurrente podría proporcionar una definición más clara del lugar de la lesión en la vía visual (por ejemplo, para los trastornos con la superposición de ERG sin embargo distinto VEP manifestaciones 18, cuando la ne...

La medición de la electrorretinograma (ERG) y de potencial evocado visual (VEP) proporcionar evaluaciones cuantitativas útiles de la integridad de la vía visual. El ERG mide las respuestas eléctricas de la retina a la estimulación de luz, mientras que el VEP mide la integridad funcional correspondiente de las vías visuales de la retina a la corteza visual primaria siguiendo el mismo evento de la luz. Este manuscrito describe un protocolo para el registro y análisis de las respuestas de ERG y PEV en un modelo de laboratorio de uso común, la rata. El ERG proporciona un índice de la integridad funcional de una serie de clases de células retinianas clave mediante la cuantificación de la respuesta eléctrica bruta de la retina a un destello de luz. Una serie coordinada de flujos iónicos inició por la aparición luz y compensado, producen cambios detectables en la tensión que se puede medir usando electrodos de superficie colocados fuera del ojo. La forma de onda resultante representa la combinación de a seRies, de componentes bien definidos, que difieren en amplitud, tiempo y frecuencia. Un cuerpo sustancial de investigación ha demostrado que estos componentes son relativamente bien conservadas a través de muchos retinas de vertebrados y que los componentes pueden estar separados unos de otros. Al seleccionar juiciosamente el estímulo (estímulo flash, fondo, intervalo inter) y la elección de las condiciones características de la forma de onda compuesta para analizar uno puede estar seguro de devolver una medida de un grupo específico de células de la retina 1,2. Estas características son la base de la utilidad y por lo tanto las aplicaciones generalizadas de la ERG como una medida no invasiva de la función de la retina. Este manuscrito se centra en la metodología para medir el ERG y el análisis de sus características para devolver información acerca de algunas de las principales clases de células en la retina, es decir, los fotorreceptores (el componente PIII), células bipolares (el componente PII) y las células ganglionares de la retina (el positivo umbral de respuesta escotópica o PSTR). <p class= &quot;Jove_content&quot;&gt; El VEP proporciona un ensayo de la respuesta cortical a la luz; primero procedente de la retina y a partir de entonces comunicada en serie a través del nervio óptico, tracto óptico, el tálamo (núcleo geniculado lateral, LGN) y la radiación óptica al área V1 de la corteza 3. En roedores, la mayoría (90-95%) de fibras del nervio óptico de cada ojo decussate 4 y inervan el contralateral del cerebro medio. A diferencia del ERG, es hasta el momento no es posible atribuir diferentes componentes de la PEV a las clases de células específicas, 5 Así, los cambios en cualquier lugar a lo largo de la vía visual podría afectar a la forma de onda VEP. Sin embargo, la PEV es una medida no invasiva útil de rendimiento visual y la integridad de las vías ópticas. El VEP, cuando se usa en conjunción con el ERG, puede proporcionar una evaluación más completa del sistema visual (es decir, la retina / vía visual). grabaciones ERG y VEP pueden llevarse a cabo de forma aislada o en combinación, dependiendo de la aplicatión. La metodología descrita en este documento permite la evaluación simultánea de electrofisiología evocado visual de la retina y la corteza de ambos ojos y ambos hemisferios en ratas anestesiadas. Esta es una manera útil de evaluar de manera más exhaustiva función de la retina y los efectos aguas arriba que los cambios en función de la retina pueden tener en la función cortical evocado visual.

<table><tbody><tr><td>Alligator clip</td><td>generic brand</td><td>HM3022</td><td>Stainless steel 26 mm clip for connecting VEP screw electrodes to cables</td></tr><tr><td>Bioamplifier</td><td>ADInstruments</td><td>ML 135</td><td>For amplifying ERG and VEP signals</td></tr><tr><td>Carboxymethylcellulose sodium 1.0%</td><td>Allergan</td><td>CAS 0009000-11-7</td><td>Viscous fluid for improving signal quality of the active ERG electrode</td></tr><tr><td>Carprofen 0.5%</td><td>Pfizer Animal Health Group</td><td>CAS 53716-49-7</td><td>Proprietary name: Rimadyl injectable (50 mg/ml). For post-surgery analgesia, diluted to 0.5% (5 mg/ml) in normal saline</td></tr><tr><td>Chlorhexadine 0.5%</td><td>Orion Laboratories</td><td>27411, 80085</td><td>For disinfecting surgical instruments</td></tr><tr><td>Circulating water bath</td><td>Lauda-K&amp;ouml;nigshoffen</td><td>MGW Lauda</td><td>For maintaining body temperature of the anesthetized animal during surgery and electrophysiological recordings</td></tr><tr><td>Dental amalgam</td><td>DeguDent GmbH</td><td>64020024</td><td>For encasing the electrode-skull assembly to make it more robust</td></tr><tr><td>Dental burr</td><td>Storz Instruments, Bausch and Lomb</td><td>#E0824A</td><td>A miniature drill head of ~ 0.7 mm diameter for making a small hole in the skull over each hemisphere to implant VEP screws</td></tr><tr><td>Drill</td><td>Bosch</td><td>Dremel 300 series</td><td>An automatic drill for trepanning</td></tr><tr><td>Electrode lead</td><td>Grass Telefactor&amp;nbsp;</td><td>F-E2-30</td><td>Platinum cables for connecting silver wire electrodes to the amplifier</td></tr><tr><td>Faraday Cage</td><td>custom-made</td><td></td><td>Ensures light proof to maintain dark adaptation. Encloses the Ganzfeld setup to improve signal to noise ratio</td></tr><tr><td>Gauze swabs</td><td>Multigate Medical Products Pty Ltd</td><td>57-100B</td><td>For drying the surgical incision and exposed skull surface during surgery</td></tr><tr><td>Ganzfeld integrating sphere</td><td>Photometric Solutions International</td><td></td><td>Custom designed light stimulator: 36 mm diameter, 13 cm aperture size</td></tr><tr><td>Velcro</td><td>VELCRO Australia Pty Ltd</td><td>VELCRO Brand Reusable Wrap</td><td>Hook-and-loop fastener to secure the electrodes and the animal on the recording platform</td></tr><tr><td>Isoflurane 99.9%</td><td>Abbott Australasia Pty Ltd</td><td>CAS 26675-46-7</td><td>Proprietary Name: Isoflo(TM) Inhalation anaaesthetic. Pharmaceutical-grade inhalation anesthetic mixed with oxygen gas for VEP electrode implant surgery</td></tr><tr><td>Ketamine&amp;nbsp;</td><td>Troy Laboratories</td><td>Ilium Ketamil</td><td>Proprietary name: Ketamil Injection, Brand: Ilium. Pharmaceutical-grade anesthetic for electrophysiological recording</td></tr><tr><td>Luxeon LEDs</td><td>Phillips Lighting Co.</td><td></td><td>For light stimulation twenty 5 W and one 1 W LEDs.</td></tr><tr><td>Micromanipulator</td><td>Harvard Apparatus</td><td>BS4 50-2625</td><td>Holds the ERG active electrode during recordings</td></tr><tr><td>Needle electrode</td><td>Grass Telefactor&amp;nbsp;</td><td>F-E2-30</td><td>Subcutaneously inserted in the tail to serve as the ground electrode for both the ERG and VEP</td></tr><tr><td>Phenylephrine 2.5% minims&amp;nbsp;</td><td>Bausch and Lomb</td><td>CAS 61-76-7</td><td>Instilled with Tropicamide to achieve maximal dilation for ERG recording</td></tr><tr><td>Povidone iodine 10%</td><td>Sanofi-Aventis</td><td>CAS 25655-41-8</td><td>Proprietory name: Betadine, Antiseptic to prepare the shaved skin for surgery 10%, 500 ml</td></tr><tr><td>Powerlab data acquisition system</td><td>ADInstruments</td><td>ML 785</td><td>Controls the LEDs</td></tr><tr><td>Proxymetacaine 0.5%</td><td>Alcon Laboratories&amp;nbsp;</td><td>CAS 5875-06-9</td><td>For corneal anaesthesia during ERG recordings</td></tr><tr><td>Saline solution</td><td>Gelflex</td><td></td><td>Non-injectable, for electroplating silver wire electrodes</td></tr><tr><td>Scope Software</td><td>ADInstruments</td><td>version 3.7.6</td><td>Simultaneously triggers the stimulus via the Powerlab system and collects data</td></tr><tr><td>Silver (fine round wire)</td><td>A&amp;amp;E metal</td><td>0.3 mm</td><td>Used to make active and inactive ERG electrodes, and the inactive VEP electrode</td></tr><tr><td>Stainless streel screws&amp;nbsp;</td><td>MicroFasterners</td><td></td><td>0.7 mm shaft diameter, 3 mm in length to be implanted over the primary visual cortex and serve as the active VEP electrodes</td></tr><tr><td>Stereotaxic frame</td><td>David Kopf</td><td>Model 900</td><td>A small animal stereotaxic instrument for locating the primary visual cortices according to Paxinos &amp;amp; Watson&#039;s 2007 rat brain atlas coordinates</td></tr><tr><td>Surgical blade</td><td>Swann-Morton Ltd.</td><td>0206</td><td>For incising the area of skin overlaying the primary visual cortex to implant the VEP electrodes</td></tr><tr><td>Suture</td><td>Shanghai Pudong Jinhuan Medical Products Co.,Ltd</td><td></td><td>3-0 silk braided suture non-absorbable, for skin retraction during VEP electrode implantation surgery</td></tr><tr><td>Tobramycine eye ointment 0.3%</td><td>Alcon Laboratories&amp;nbsp;</td><td>CAS 32986-56-4</td><td>Proprietary name: Tobrex. Prophylactic antibiotic ointment applied around the skin wound after surgery</td></tr><tr><td>Tropicamide 0.5%</td><td>Alcon Laboratories&amp;nbsp;</td><td>CAS 1508-75-4</td><td>Proprietary name: 0.5% Mydriacyl eye drop, Instilled to achieve mydriasis for ERG recording</td></tr><tr><td>Xylazine</td><td>Troy Laboratories</td><td>Ilium Xylazil-100</td><td>Pharmaceutical-grade anesthetic for electrophysiological recording</td></tr><tr><td>Pipette tip</td><td>Eppendorf Pty Ltd</td><td>0030 073.169</td><td>Eppendorf epTIPS 100 - 5,000 ml, for custom-made electrodes</td></tr><tr><td>Microsoft Office Excel</td><td>Microsoft</td><td>version 2010</td><td>spreadsheet software for data analysis</td></tr><tr><td>Lethabarb Euthanazia Injection</td><td>Virbac (Australia) Pty Ltd</td><td>LETHA450</td><td>325 mg/ml pentobarbital sodium for rapid euthanazia</td></tr></tbody></table>

simultaneous recording of electroretinography and visual evoked potentials in anesthetized rats

The electroretinogram (ERG) and visual evoked potential (VEP) are commonly used to assess the integrity of the visual pathway. The ERG measures the electrical responses of the retina to light stimulation, while the VEP measures the corresponding functional integrity of the visual pathways from the retina to the primary visual cortex following the same light event. The ERG waveform can be broken down into components that reflect responses from different retinal neuronal and glial cell classes. The early components of the VEP waveform represent the integrity of the optic nerve and higher cortical centers. These recordings can be conducted in isolation or together, depending on the application. The methodology described in this paper allows simultaneous assessment of retinal and cortical visual evoked electrophysiology from both eyes and both hemispheres. This is a useful way to more comprehensively assess retinal function and the upstream effects that changes in retinal function can have on visual evoked cortical function.

El ERG una onda (&gt; -1.38 registro cd.sm -2), b-ondas (&gt; - 4,99 log cd.sm -2) RTS (&lt;- 4,99 log cd.sm -2) y los VEP (&gt; - 0,52 cd.sm log -2) se registraron simultáneamente (Figura 1 y 3). En destellos muy tenue, un RTS positivo (PSTR) es visto en aproximadamente 110 milisegundos después del flash, y un STR negativo (NSTR) a aproximadamente 220 ​​mseg (Figuras 1 y 2). Un ERG con una gran onda b, p...

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Simultaneous Recording of Electroretinography and Visual Evoked Potentials in Anesthetized Rats

This protocol describes simultaneous measurement of electroretinogram and visual evoked potentials in anesthetized rats.

Grabación simultánea de Electrorretinografía y los potenciales evocados visuales en ratas anestesiadas

The electroretinogram (ERG) and visual evoked potential (VEP) are commonly used to assess the integrity of the visual pathway. The ERG measures the ...

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Neuroscience

12.3K vistas.  University of Melbourne. This protocol describes simultaneous measurement of electroretinogram and visual evoked potentials in anesthetized rats. 

Video: Simultaneous Recording of Electroretinography and Visual Evoked Potentials in Anesthetized Rats

Implantation and Recording of Wireless Electroretinogram and Visual Evoked Potential in Conscious Rats

The full-field electroretinogram (ERG) and visual evoked potential (VEP) are useful tools to assess retinal and visual pathway integrity in both laboratory and clinical settings. Currently, preclinical ERG and VEP measurements are performed with anesthesia to ensure stable electrode placements. However, the very presence of anesthesia has been shown to contaminate normal physiological responses. To overcome these anesthesia confounds, we develop a novel platform to assay ERG and VEP in conscious rats. Electrodes are surgically implanted sub-conjunctivally on the eye to assay the ERG and epidurally over the visual cortex to measure the VEP. A range of amplitude and sensitivity/timing parameters are assayed for both the ERG and VEP at increasing luminous energies. The ERG and VEP signals are shown to be stable and repeatable for at least 4 weeks post surgical implantation. This ability to record ERG and VEP signals without anesthesia confounds in the preclinical setting should provide superior translation to clinical data.

We show surgical implantation and Recording procedures to measure visual electrophysiological signals from the eye (electroretinogram) and brain (visual evoked potential) in conscious rats, which is more analogous to the human condition where recordings are conducted without anesthesia confounds.

Implantación y grabación de Electrorretinograma Wireless y del potencial evocado visual en ratas conscientes

The full-field electroretinogram (ERG) and visual evoked potential (VEP) are useful tools to assess retinal and visual pathway integrity in both ...

Investigación

Comportamiento

Using the Electroretinogram to Assess Function in the Rodent Retina and the Protective Effects of Remote Limb Ischemic Preconditioning

The ERG is the sum of all retinal activity. The ERG is usually recorded from the cornea, which acts as an antenna that collects and sums signals from the retina. The ERG is a sensitive measure of changes in retinal function that are pan-retinal, but is less effective for detecting damage confined to a small area of retina. In the present work we describe how to record the &#8216;flash&#8217; ERG, which is the potential generated when the retina is exposed to a brief light flash. We describe methods of anaesthesia, mydriasis and corneal management during recording; how to keep the retina dark adapted; electrode materials and placement; the range and calibration of stimulus energy; recording parameters and the extraction of data. We also describe a method of inducing ischemia in one limb, and how to use the ERG to assess the effects of this remote-from-the-retina ischemia on retinal function after light damage. A two-flash protocol is described which allows isolation of the cone-driven component of the dark-adapted ERG, and thereby the separation of the rod and cone components. Because it can be recorded with techniques that are minimally invasive, the ERG has been widely used in studies of the physiology, pharmacology and toxicology of the retina. We describe one example of this usefulness, in which the ERG is used to assess the function of the light-damaged retina, with and without a neuroprotective intervention; preconditioning by remote ischemia.

The electroretinogram (ERG) is an electrical potential generated by the retina in response to light. This paper describes how to use the ERG to assess retinal function, in dark-adapted rats, and how it can be can be used to assess a neuroprotective intervention, in the present case remote ischemic preconditioning.

Utilizando el Electrorretinograma para evaluar la función en el Roedor Retina y los efectos protectores de distancia Limb Preacondicionamiento Isquémico

The ERG is the sum of all retinal activity. The ERG is usually recorded from the cornea, which acts as an antenna that collects and sums signals from the ...

Neurociencias

Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to monitor the disease course in the follow-up period. Changes in the VEP parameters closely correlate with pathological damage in the optic nerve. This protocol provides a detailed description about the rodent model of optic nerve microinjection, in which a partial demyelination lesion is produced in the optic nerve. VEP recording techniques are also discussed. Using skull implanted electrodes, we are able to acquire reproducible intra-session and between-session VEP traces. VEPs can be recorded on individual animals over a period of time to assess the functional changes in the optic nerve longitudinally. The optic nerve demyelination model, in conjunction with the VEP recording protocol, provides a tool to investigate the disease processes associated with demyelination and remyelination, and can potentially be employed to evaluate the effects of new remyelinating drugs or neuroprotective therapies.

Focal demyelination is induced in the optic nerve using lysolecithin microinjection. Visual evoked potentials are recorded via skull electrodes implanted over the visual cortex to examine the signal conduction along the visual pathway in vivo. This protocol details the surgical procedures underlying electrode implantation and optic nerve microinjection.

Grabación de potencial evocado visual en un modelo de rata de Experimental del Nervio Óptico Desmielinización

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to ...

Concurrent Recording of Co-localized Electroencephalography and Local Field Potential in Rodent

Although electroencephalography (EEG) is widely used as a non-invasive technique for recording neural activities of the brain, our understanding of the neurogenesis of EEG is still very limited. Local field potentials (LFPs) recorded via a multi-laminar microelectrode can provide a more detailed account of simultaneous neural activity across different cortical layers in the neocortex, but the technique is invasive. Combining EEG and LFP measurements in a pre-clinical model can greatly enhance understanding of the neural mechanisms involved in the generation of EEG signals, and facilitate the derivation of a more realistic and biologically accurate mathematical model of EEG. A simple procedure for acquiring concurrent and co-localized EEG and multi-laminar LFP signals in the anesthetized rodent is presented here. We also investigated whether EEG signals were significantly affected by a burr hole drilled in the skull for the insertion of a microelectrode. Our results suggest that the burr hole has a negligible impact on EEG recordings.

This protocol describes a simple method for concurrent recording of co-localized electroencephalography (EEG) and multi-laminar local field potential in an anesthetized rat. A burr hole drilled in the skull for the insertion of a microelectrode is shown to produce negligible distortion of the EEG signal.

Grabación concurrente de electroencefalografía Co localizada y potencial de campo Local en roedores

Although electroencephalography (EEG) is widely used as a non-invasive technique for recording neural activities of the brain, our understanding of the ...

Electroretinogram Recording for Infants and Children under Anesthesia to Achieve Optimal Dark Adaptation and International Standards

Electroretinogram (ERG) is the only clinical objective test available to assess retinal function. Full-field ERG (ffERG) measures the panretinal rod and cone photoreceptor function as well as inner retinal function and is an important measure in the diagnosis and management of inherited retinal diseases as well as inflammatory, toxic, and nutritional retinopathies. Adhering to international standards and maintaining retinal dark adaptation are critical to acquire valid and reliable dark-adapted (scotopic) and light-adapted (photopic) ffERG responses. Performing ffERG in infants and children is challenging and often requires general anesthesia in the operating room. However, maintaining retinal dark adaptation in the operating room is becoming increasingly difficult given the numerous light sources from anesthesiology monitoring systems and other equipment. A practical and widely applicable method for ffERG testing is described in the operating room that optimizes retinal dark adaptation. The method reduces operating room time by dark-adapting the patient before general anesthesiology is instituted. The operating room is modified for dark adaptation and any remaining light source in the darkened operating room is minimized with the use of a modified portable foldable darkroom that encloses the patient&#8217;s head and the ERG examiner during ffERG scotopic recordings. The simple method adheres to ffERG international standards and provides valid reliable scotopic and photopic ffERG recordings that are critical to assess objective retinal function in this young age group where subjective assessment of visual function such as visual acuity and visual fields are not possible. Furthermore, the ffERG is the gold standard clinical test in detecting early onset inherited retinal diseases including Leber congenital amaurosis where approved gene therapy has become available. In sedated conditions, very low amplitude ffERG signals can be detected due to minimal orbicularis muscle activity interference, which is particularly relevant in patients after gene therapy to detect improved amplitude responses.

Adhering to international standards and maintaining retinal dark adaptation are critical to acquire valid full-field electroretinogram responses in the diagnosis and management of inherited retinal diseases. A practical protocol using a portable darkroom is provided to obtain full-field&#160;electroretinogram for infants and children under sedation or general anesthesia in the operating room setting.

Grabación de electrorretinogramas para bebés y niños bajo anestesia para lograr una adaptación óptima de la oscuridad y estándares internacionales

Electroretinogram (ERG) is the only clinical objective test available to assess retinal function. Full-field ERG (ffERG) measures the panretinal rod and ...

Medicina

Full-Circle Cauterization of Limbal Vascular Plexus for Surgically Induced Glaucoma in Rodents

Glaucoma, the second leading cause of blindness worldwide, is a heterogeneous group of ocular disorders characterized by structural damage to the optic nerve and retinal ganglion cell (RGC) degeneration, resulting in visual dysfunction by interrupting the transmission of visual information from the eye to the brain. Elevated intraocular pressure is the most important risk factor; thus, several models of ocular hypertension have been developed in rodents by either genetic or experimental approaches to investigate the causes and effects of the disease. Among those, some limitations have been reported such as surgical invasiveness, inadequate functional assessment, requirement of extensive training, and highly variable extension of retinal damage. The present work characterizes a simple, low-cost, and efficient method to induce ocular hypertension in rodents, based on low-temperature, full-circle cauterization of the limbal vascular plexus, a major component of aqueous humor drainage. The new model provides a technically easy, noninvasive, and reproducible subacute ocular hypertension, associated with progressive RGC and optic nerve degeneration, and a unique post-operative clinical recovery rate that allows in vivo functional studies by both electrophysiological and behavioral methods.

The goal of this protocol is to characterize a novel model of glaucomatous neurodegeneration based on 360&#176; thermic cauterization of limbal vascular plexus, inducing subacute ocular hypertension.

Cauterización de círculo completo del plexo vascular limbal para el glaucoma inducido quirúrgicamente en roedores

Glaucoma, the second leading cause of blindness worldwide, is a heterogeneous group of ocular disorders characterized by structural damage to the optic ...

Preparing a Rat Model to Assess Visual Pathway Integrity Using an Electrophysiology Setup

Source: Nguyen, C. T. et al., <a href="https://app.jove.com/v/54158">Simultaneous Recording of Electroretinography and Visual Evoked Potentials in Anesthetized Rats.</a>&#160;J. Vis. Exp. (2016)
This video demonstrates the preparation of a rat model to study retinal health and visual pathway integrity. Visual evoked potential and electroretinography reference and active electrodes are connected to the rat, followed by aligning the platform with the rat in front of the Ganzfeld bowl for even retinal illumination and closing the Faraday cage to avoid external interference.

Preparación de un modelo de rata para evaluar la integridad de la vía visual mediante una configuración de electrofisiología

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. ...

JoVE Encyclopedia of Experiments

Neurophysiology

Electrophysiology Techniques

Direct-Coupled Electroretinogram Recording of the Retinal Pigment Epithelium in a Mouse

Source: Miyagishima, K. J., et al. <a href="https://app.jove.com/v/61491">Direct-Coupled Electroretinogram (DC-ERG) for Recording the Light-Evoked Electrical Responses of the Mouse Retinal Pigment Epithelium.</a> J. Vis. Exp. (2020).
This video demonstrates the recording of a direct-coupled electroretinogram (DC-ERG) on a dark-adapted, anesthetized mouse retinal pigment epithelium (RPE). After applying dilating drops, the animal is placed in a recording setup, and the capillary electrode filled with a salt buffer is placed on the cornea. After establishing the baseline, DC-ERG is recorded.

Registro de electrorretinograma de acoplamiento directo del epitelio pigmentario de la retina en un ratón

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. Mouse ...

Imaging and Optical Techniques

Recording of Visual Evoked Potentials via the Skull Electrodes in a Rat Model

Source: You, Y., et al. <a href="https://app.jove.com/v/52934">Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination.</a> J. Vis. Exp. (2015).
This video demonstrates the process of measuring visual evoked potentials or VEPs in a dark-adapted, anesthetized rat with pre-implanted skull electrodes, which record the electrical signals from the brain&#39;s visual cortex in response to light stimuli.

Registro de potenciales evocados visuales a través de los electrodos del cráneo en un modelo de rata

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. VEP ...

Concurrent Electroencephalographic and Local Field Potential Recordings in an Anesthetized Rat

Source: Kang, S., et al. <a href="https://app.jove.com/v/56447">Concurrent Recording of Co-localized Electroencephalography and Local Field Potential in Rodent.</a> J. Vis. Exp. (2017).
This video demonstrates the procedure for concurrent recordings of co-localized electroencephalography (EEG) and local field potentials (LFPs) in an anesthetized rat. The process involves preparing the rat and attaching stimulating electrodes to its whisker pads. An EEG spider electrode is placed on the rat&#39;s skull for surface EEG measurements. At the same time, a multi-channel microelectrode is inserted into a specific brain region through a burr hole in the skull to record neural activity from a localized brain area.