Name: simultaneous fmri and electrophysiology in the rodent brain
Uploaded: 2010-08-19T17:00:00
Description: Watch this Scientific Journal Video about Simultaneous fMRI and Electrophysiology in the Rodent Brain at JoVE.com

The work was supported by NIH 1 R21NS057718-01.

1. This is a non-survival surgery. The first step is implantation of the electrodes. In this example, electrodes will be implanted in the forepaw regions of primary somatosensory cortex of both hemispheres.
<ol>
	<li>Anesthetize the rat (male SD rat, 200-300 g) with 2% isoflurane and fix into place on a stereotactic surgical system. Before beginning surgery, ensure that the animal is well anesthetized and exhibits no response to a toe pinch. Remove the fur before opening the scalp. Separate the muscle and other tis...

<ol>
	<li>Gruetter, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automatic,+localized+in+vivo+adjustment+of+all+first-+and+second-order+shim+coils.">Automatic, localized in vivo adjustment of all first- and second-order shim coils.</a> Magn Reson Med. 29 (6), 804-804 (1993).</li><li>Logothetis, N. K., Pauls, J., Augath, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurophysiological+investigation+of+the+basis+of+the+fMRI+signal.">Neurophysiological investigation of the basis of the fMRI signal.</a> Nature. 412 (6843), 150-150 (2001).</li><li>Nir, Y., Fisch, L., Mukamel, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coupling+between+neuronal+firing+rate,+gamma+LFP,+and+BOLD+fMRI+is+related+to+interneuronal+correlations.">Coupling between neuronal firing rate, gamma LFP, and BOLD fMRI is related to interneuronal correlations.</a> Curr Biol. 17 (15), 1275-1275 (2007).</li></ol>

Both electrophysiological recording and BOLD fMRI are separately well-developed techniques. However, simultaneously recording and imaging is challenging due to the mutual interference2 of the two modalities. Here we provide a possible solution for combined experiments in the rodent. The modified method of electrode implantation minimizes influence on the image quality, and the artifact removal for the electrical recordings is necessary to remove the noise induced by image acquisition. Simultaneous imaging and ...

simultaneous fmri and electrophysiology in the rodent brain

To examine the neural basis of the blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI) signal, we have developed a rodent model in which functional MRI data and in vivo intracortical recording can be performed simultaneously. The combination of MRI and electrical recording is technically challenging because the electrodes used for recording distort the MRI images and the MRI acquisition induces noise in the electrical recording. To minimize the mutual interference of the two modalities, glass microelectrodes were used rather than metal and a noise removal algorithm was implemented for the electrophysiology data. In our studies, two microelectrodes were separately implanted in bilateral primary somatosensory cortices (SI) of the rat and fixed in place. One coronal slice covering the electrode tips was selected for functional MRI. Electrode shafts and fixation positions were not included in the image slice to avoid imaging artifacts. The removed scalp was replaced with toothpaste to reduce susceptibility mismatch and prevent Gibbs ringing artifacts in the images. The artifact structure induced in the electrical recordings by the rapidly-switching magnetic fields during image acquisition was characterized by averaging all cycles of scans for each run. The noise structure during imaging was then subtracted from original recordings. The denoised time courses were then used for further analysis in combination with the fMRI data. As an example, the simultaneous acquisition was used to determine the relationship between spontaneous fMRI BOLD signals and band-limited intracortical electrical activity. Simultaneous fMRI and electrophysiological recording in the rodent will provide a platform for many exciting applications in neuroscience in addition to elucidating the relationship between the fMRI BOLD signal and neuronal activity.

Watch this Scientific Journal Video about Simultaneous fMRI and Electrophysiology in the Rodent Brain at JoVE.com

Simultaneous fMRI and Electrophysiology in the Rodent Brain

We have developed a method for simultaneous functional magnetic resonance imaging and electrophysiological recording in the rodent brain, providing a platform for the investigation of the relationship between neural activity and the blood oxygenation level dependent (BOLD) MRI signal.

To examine the neural basis of the blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI) signal, we have developed a rodent model in ...

Research

JoVE Journal

Neuroscience

Design and Construction of a Cost Effective Headstage for Simultaneous Neural Stimulation and Recording in the Water Maze

Headstage preamplifiers and source followers are commonly used to study neural activity in behavioral neurophysiology experiments. Available commercial ...

Combining Transcranial Magnetic Stimulation and fMRI to Examine the Default Mode Network

The default mode network is a group of brain regions that are active when an individual is not focused on the outside world and the brain is at "wakeful ...

Co-analysis of Brain Structure and Function using fMRI and Diffusion-weighted Imaging

The study of complex computational systems is facilitated by network maps, such as circuit diagrams. Such mapping is particularly informative when ...

Simultaneous Electroencephalography, Real-time Measurement of Lactate Concentration and Optogenetic Manipulation of Neuronal Activity in the Rodent Cerebral Cortex

Samtidig Elektroencefalografi, Real-time måling af laktat Koncentration og Optogenetic Manipulation af neuronale aktivitet i Rodent Cerebral Cortex

Although the brain represents less than 5% of the body  by mass, it utilizes approximately one quarter of the glucose used by the body  at rest1. The ...

Deep Brain Stimulation with Simultaneous fMRI in Rodents

Dyb Brain Stimulation med samtidig fMRI i Gnavere

In order to visualize the global and downstream neuronal responses to deep brain stimulation (DBS) at various targets, we have developed a protocol for ...

In vivo Optogenetic Stimulation of the Rodent Central Nervous System

In vivo Optogenetic Stimulation of the Rodent Central Nervous System

In vivo optogenetic Stimulering af Rodent centralnervesystemet

The ability to probe defined neural circuits in awake, freely-moving animals with cell-type specificity, spatial precision, and high temporal resolution ...

Simultaneous Electrophysiological Recording and Micro-injections of Inhibitory Agents in the Rodent Brain

Samtidig Elektrofysiologisk optagelse og Micro-injektioner af inhiberende Agents i Rodent Brain

Here we describe a method for the construction of a single-use &#8220;injectrode&#8221; using commercially accessible and affordable parts. A probing ...

Personalized Needles for Microinjections in the Rodent Brain

Personlig nåle til Microinjections i gnavere hjernen

Microinjections have been used for a long time for the delivery of drugs or toxins within specific brain areas and, more recently, they have been used to ...

Evaluation of Synapse Density in Hippocampal Rodent Brain Slices

Evaluering af Synapse tæthed i hippocampus gnaver hjernen skiver

In the brain, synapses are specialized junctions between neurons, determining the strength and spread of neuronal signaling. The number of synapses is ...

Simultaneous Cryosectioning of Multiple Rodent Brains

Samtidige Cryosectioning af flere gnaver hjerner

Histology and immunohistochemistry are routine methods of analysis to visualize microscopic anatomy and localize proteins within biological tissue. In ...