Name: Using Neuron Spiking Activity to Trigger Closed-Loop Stimuli in Neurophysiological Experiments (Video) | JoVE Journal
Uploaded: 2019-11-12T11:00:00.000+00:00
Duration: 5 min 19 s
Description: Learn closed-loop stimulation for studying causal brain interactions using awake rat recordings. This MATLAB-based protocol enables cost-effective real-time triggering of stimuli based on neuronal spiking activity.

ai_agent_IP

ai_agent

maintenance

instantTrialDurationMinutes

isBiopharma

enableNewMyJoveSectionDesign

educationFeatures

seoMetaApi

ai_copilot_institution_blacklist

ai_chat_institution_blacklist

freeAccessWindow

ssoRoleCapture

scheduledMaintenanceBanner

joveLabsFeatures

disable_autoplay_for_bots

extended_trial_duration

5 minutes

This work was supported by NSERC Discovery grants to AL and AG.

All procedures described here were performed under an Animal Research Protocol approved by the University of Lethbridge Animal Welfare Committee.
1. Surgery
NOTE: The surgery procedures used to implant probes for neurophysiological recordings have been presented in other publications24,25,26. The exact details of the surgery for closed-loop stimulation depend on the type of recording probes used and the brain areas targeted. In most cases, however, a typical surgery will consist of the following steps.
<ol>
	<li>Bring to the surgery room a cage with a rat to be implanted with a silicone probe or electrode array to record neuronal activity.</li>
	<li>Anesthetize the rodent with 2-2.5% isoflurane and fix the head in a stereotaxic frame. Ensure that the animal is unconscious during surgery by observing any motoric reaction to mild tactile stimuli25.</li>
	<li>Apply an eye ointment to minimize dryness during the surgery.</li>
	<li>Shave the surgical area and disinfect the skin with 2% chlorhexidine solution and 70% isopropyl alcohol.</li>
	<li>Inject lidocaine (5 mg/kg) under the scalp over the brain area where electrodes will be implanted.</li>
	<li>Make an incision of the scalp over the area of future implant, and use a scalpel and cotton swab to clear the periosteum from the exposed skull25.</li>
	<li>Drill 4-8 holes in the skull for implantation of anchor screws (~0.5 mm) as structural support for the implant25. Attach the screws to the skull by inserting them in the holes and ensure that they are held firmly in place.</li>
	<li>Drill the craniotomy at the specified coordinates, and inset the microdrive/probe implant. 
	NOTE: The described protocol for closed-loop stimulation will work for any brain region in which the electrodes are inserted.</li>
	<li>Fix the microdrive/probe and any required electrical interface connector to the skull using dental acrylic. The amount of dental acrylic should be enough to firmly attach the implant, but it should not come in contact with the surrounding soft tissue25.</li>
	<li>After surgery, closely monitor the animal until it has regained sufficient consciousness to maintain sternal recumbency25. For the subsequent 3 days, administer subcutaneously an analgesic (e.g. Metacam, 1 mg/kg), and an antibiotic to prevent infection (e.g. enrofloxacin, 10 mg/kg). 
	NOTE: Animals are typically left to recover from surgery for one week prior to any testing or recording.</li>
</ol>
2. Software installation
NOTE: This was tested on Windows 10, 64 bit version.
<ol>
	<li>Install data acquisition and processing software.
	<ol>
		<li>Install the data acquisition system Cheetah 6.4 (https://neuralynx.com/software/category/sw-acquisition-control), which includes libraries to interact with the Cheetah Acquisition System.</li>
		<li>Install SpikeSort3D (https://neuralynx.com/software/spikesort-3d) or any other software that uses KlustaKwik27 for spike sorting. The online detection software uses the cluster definitions from the KlustaKwik engine. This software may run on the same computer, or it may run on separate computers that are on the same network.</li>
		<li>Install the NetComDevelopmentPackage (https://github.com/leomol/cheetah-interface/blob/master/NetComDevelopmentPackage_v3.1.0), which can be also downloaded from https://neuralynx.com/software/netcom-development-package.</li>
	</ol>
	</li>
	<li>Install Matlab (https://www.mathworks.com/downloads/; code was tested on Matlab version R2018a). Make sure that Matlab is enabled in the Windows firewall. Normally a pop-up will come up during the first connection.
	<ol>
		<li>Log in to a Matlab account. Choose the licence. Choose the version. Choose the operating system.</li>
	</ol>
	</li>
	<li>Download the following library for online event triggering from: https://github.com/leomol/cheetah-interface and extract files to the computer&#8217;s &#8216;Documents/Matlab&#8217; folder. A copy of the code is provided in the accompanying Supplemental Materials.</li>
</ol>
3. Initial data acquisition
<ol>
	<li>Start data acquisition using Cheetah software.</li>
	<li>Record a few minutes of spiking data to populate template waveforms.</li>
	<li>Stop the data acquisition and perform spike sorting on the recorded data.
	<ol>
		<li>Open SpikeSort3D, click File | Menu | Load Spike File, and select a spike file from the folder with recorded data.</li>
		<li>Click Cluster Menu and then Autocluster using KlustaKwik, leaving the default settings and click Run.</li>
	</ol>
	</li>
</ol>
4. Closed-loop experiment
<ol>
	<li>Resume data acquisition in Cheetah.</li>
	<li>Open Matlab.
	<ol>
		<li>Open ClosedLoop.m and click on Run. Alternatively, in the Matlab command window, execute ClosedLoop(). Ensure that ClosedLoop.m is on the Matlab path. If the user wants to employ a custom function to call on every trigger, execute ClosedLoop(&#8216;-callback&#8217;, customFunction) instead, where customFunction is a handle to that function.</li>
		<li>Load the spike information defined on the initial recording by clicking on Load, browsing to the recording folder, and selecting one of the spiking data files (.ntt, .nse).</li>
		<li>Select one or multiple neurons that will trigger stimulation by clicking the checkbox under the plotted waveforms.</li>
		<li>Define the minimum number of neurons that will trigger stimulation by typing an integer in the &#8220;min matches&#8221; text box; and define the time window in which spikes matching different waveforms are considered co-active by typing a number in the &#8220;window&#8221; text box.</li>
		<li>Click Send to start. This will begin online triggering of events (tones as default) based on spiking activity of selected neurons.</li>
	</ol>
	</li>
</ol>

<ol><li>Grosenick, L., Marshel, J. H., Deisseroth, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Closed-loop+and+activity-guided+optogenetic+control%5BTitle%5D)+AND+%22Neuron%22%5BJournal%5D)">Closed-loop and activity-guided optogenetic control.</a> Neuron. 86 (1), 106-139 (2015).</li>
<li>Armstrong, C., Krook-Magnuson, E., Oijala, M., Soltesz, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Closed-loop+optogenetic+intervention+in+mice%5BTitle%5D)+AND+%22Nature+Protocols%22%5BJournal%5D)">Closed-loop optogenetic intervention in mice.</a> Nature Protocols. 8 (8), 1475-1493 (2013).</li>
<li>Siegle, J. H., Wilson, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Enhancement+of+encoding+and+retrieval+functions+through+theta+phase-specific+manipulation+of+hippocampus%5BTitle%5D)+AND+%22Elife%22%5BJournal%5D)">Enhancement of encoding and retrieval functions through theta phase-specific manipulation of hippocampus.</a> Elife. 3, 03061(2014).</li>
<li>Paz, J. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Closed-loop+optogenetic+control+of+thalamus+as+a+tool+for+interrupting+seizures+after+cortical+injury%5BTitle%5D)+AND+%22Nature+neuroscience%22%5BJournal%5D)">Closed-loop optogenetic control of thalamus as a tool for interrupting seizures after cortical injury.</a> Nature neuroscience. 16 (1), 64-70 (2013).</li>
<li>Krook-Magnuson, E., Armstrong, C., Oijala, M., Soltesz, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((On-demand+optogenetic+control+of+spontaneous+seizures+in+temporal+lobe+epilepsy%5BTitle%5D)+AND+%22Nature+Communications%22%5BJournal%5D)">On-demand optogenetic control of spontaneous seizures in temporal lobe epilepsy.</a> Nature Communications. 4, 1376(2013).</li>
<li>Berényi, A., Belluscio, M., Mao, D., Buzsáki, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Closed-loop+control+of+epilepsy+by+transcranial+electrical+stimulation%5BTitle%5D)+AND+%22Science%22%5BJournal%5D)">Closed-loop control of epilepsy by transcranial electrical stimulation.</a> Science. 337 (6095), 735-737 (2012).</li>
<li>Peters, T. E., Bhavaraju, N. C., Frei, M. G., Osorio, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Network+system+for+automated+seizure+detection+and+contingent+delivery+of+therapy%5BTitle%5D)+AND+%22Journal+of+Clinical+Neurophysiology%22%5BJournal%5D)">Network system for automated seizure detection and contingent delivery of therapy.</a> Journal of Clinical Neurophysiology. 18 (6), 545-549 (2001).</li>
<li>Fountas, K. N., Smith, J. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aFountas%2C+KN+%22Operative+Neuromodulation%22">Operative Neuromodulation</a>. , Springer. 357-362 (2007).</li>
<li>Heck, C. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Two-year+seizure+reduction+in+adults+with+medically+intractable+partial+onset+epilepsy+treated+with+responsive+neurostimulation%3A+final+results+of+the+RNS+System+Pivotal+trial%5BTitle%5D)+AND+%22Epilepsia%22%5BJournal%5D)">Two-year seizure reduction in adults with medically intractable partial onset epilepsy treated with responsive neurostimulation: final results of the RNS System Pivotal trial.</a> Epilepsia. 55 (3), 432-441 (2014).</li>
<li>Osorio, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Automated+seizure+abatement+in+humans+using+electrical+stimulation%5BTitle%5D)+AND+%22Annals+of+Neurology%22%5BJournal%5D)">Automated seizure abatement in humans using electrical stimulation.</a> Annals of Neurology. 57 (2), 258-268 (2005).</li>
<li>Sun, F. T., Morrell, M. J., Wharen, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Responsive+cortical+stimulation+for+the+treatment+of+epilepsy%5BTitle%5D)+AND+%22Neurotherapeutics%22%5BJournal%5D)">Responsive cortical stimulation for the treatment of epilepsy.</a> Neurotherapeutics. 5 (1), 68-74 (2008).</li>
<li>Fountas, K. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Implantation+of+a+closed-loop+stimulation+in+the+management+of+medically+refractory+focal+epilepsy%5BTitle%5D)+AND+%22Stereotactic+and+Functional+Neurosurgery%22%5BJournal%5D)">Implantation of a closed-loop stimulation in the management of medically refractory focal epilepsy.</a> Stereotactic and Functional Neurosurgery. 83 (4), 153-158 (2005).</li>
<li>Abbott, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Neuroprosthetics%3A+In+search+of+the+sixth+sense%5BTitle%5D)+AND+%22Nature%22%5BJournal%5D)">Neuroprosthetics: In search of the sixth sense.</a> Nature. 442, (2006).</li>
<li>Venkatraman, S., Elkabany, K., Long, J. D., Yao, Y., Carmena, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+system+for+neural+recording+and+closed-loop+intracortical+microstimulation+in+awake+rodents%5BTitle%5D)+AND+%22IEEE+Transactions+on+Biomedical+Engineering%22%5BJournal%5D)">A system for neural recording and closed-loop intracortical microstimulation in awake rodents.</a> IEEE Transactions on Biomedical Engineering. 56 (1), 15-22 (2009).</li>
<li>Nguyen, T. K. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Closed-loop+optical+neural+stimulation+based+on+a+32-channel+low-noise+recording+system+with+online+spike+sorting%5BTitle%5D)+AND+%22Journal+of+Neural+Engineering%22%5BJournal%5D)">Closed-loop optical neural stimulation based on a 32-channel low-noise recording system with online spike sorting.</a> Journal of Neural Engineering. 11 (4), 046005(2014).</li>
<li>Laxpati, N. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Real-time+in+vivo+optogenetic+neuromodulation+and+multielectrode+electrophysiologic+recording+with+NeuroRighter%5BTitle%5D)+AND+%22Frontiers+in+Neuroengineering%22%5BJournal%5D)">Real-time in vivo optogenetic neuromodulation and multielectrode electrophysiologic recording with NeuroRighter.</a> Frontiers in Neuroengineering. 7, 40(2014).</li>
<li>Su, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+wireless+32-channel+implantable+bidirectional+brain+machine+interface%5BTitle%5D)+AND+%22Sensors%22%5BJournal%5D)">A wireless 32-channel implantable bidirectional brain machine interface.</a> Sensors. 16 (10), 1582(2016).</li>
<li>Ciliberti, D., Kloosterman, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Falcon%3A+a+highly+flexible+open-source+software+for+closed-loop+neuroscience%5BTitle%5D)+AND+%22Journal+of+Neural+Engineering%22%5BJournal%5D)">Falcon: a highly flexible open-source software for closed-loop neuroscience.</a> Journal of Neural Engineering. 14 (4), 045004(2017).</li>
<li>Luczak, A., Bartho, P., Harris, K. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Gating+of+sensory+input+by+spontaneous+cortical+activity%5BTitle%5D)+AND+%22The+Journal+of+Neuroscience%22%5BJournal%5D)">Gating of sensory input by spontaneous cortical activity.</a> The Journal of Neuroscience. 33 (4), 1684-1695 (2013).</li>
<li>Luczak, A., Barthó, P., Harris, K. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Spontaneous+events+outline+the+realm+of+possible+sensory+responses+in+neocortical+populations%5BTitle%5D)+AND+%22Neuron%22%5BJournal%5D)">Spontaneous events outline the realm of possible sensory responses in neocortical populations.</a> Neuron. 62 (3), 413-425 (2009).</li>
<li>Schjetnan, A. G., Luczak, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Recording+Large-scale+Neuronal+Ensembles+with+Silicon+Probes+in+the+Anesthetized+Rat%5BTitle%5D)+AND+%22Journal+of+Visualized+Experiments%22%5BJournal%5D)">Recording Large-scale Neuronal Ensembles with Silicon Probes in the Anesthetized Rat.</a> Journal of Visualized Experiments. (56), (2011).</li>
<li>Bermudez Contreras, E. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Formation+and+reverberation+of+sequential+neural+activity+patterns+evoked+by+sensory+stimulation+are+enhanced+during+cortical+desynchronization%5BTitle%5D)+AND+%22Neuron%22%5BJournal%5D)">Formation and reverberation of sequential neural activity patterns evoked by sensory stimulation are enhanced during cortical desynchronization.</a> Neuron. 79 (3), 555-566 (2013).</li>
<li>Girardeau, G., Benchenane, K., Wiener, S. I., Buzsáki, G., Zugaro, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Selective+suppression+of+hippocampal+ripples+impairs+spatial+memory%5BTitle%5D)+AND+%22Nature+Neuroscience%22%5BJournal%5D)">Selective suppression of hippocampal ripples impairs spatial memory.</a> Nature Neuroscience. 12 (10), 1222-1223 (2009).</li>
<li>Schjetnan, A. G. P., Luczak, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Recording+large-scale+neuronal+ensembles+with+silicon+probes+in+the+anesthetized+rat%5BTitle%5D)+AND+%22Journal+of+Visualized+Experiments%22%5BJournal%5D)">Recording large-scale neuronal ensembles with silicon probes in the anesthetized rat.</a> Journal of Visualized Experiments. (56), (2011).</li>
<li>Vandecasteele, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Large-scale+recording+of+neurons+by+movable+silicon+probes+in+behaving+rodents%5BTitle%5D)+AND+%22Journal+of+Visualized+Experiments%22%5BJournal%5D)">Large-scale recording of neurons by movable silicon probes in behaving rodents.</a> Journal of Visualized Experiments. (61), e3568(2012).</li>
<li>Sariev, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Implantation+of+Chronic+Silicon+Probes+and+Recording+of+Hippocampal+Place+Cells+in+an+Enriched+Treadmill+Apparatus%5BTitle%5D)+AND+%22Journal+of+Visualized+Experiments%22%5BJournal%5D)">Implantation of Chronic Silicon Probes and Recording of Hippocampal Place Cells in an Enriched Treadmill Apparatus.</a> Journal of Visualized Experiments. (128), e56438(2017).</li>
<li>Harris, K. D., Henze, D. A., Csicsvari, J., Hirase, H., Buzsáki, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Accuracy+of+tetrode+spike+separation+as+determined+by+simultaneous+intracellular+and+extracellular+measurements%5BTitle%5D)+AND+%22Journal+of+Neurophysiology%22%5BJournal%5D)">Accuracy of tetrode spike separation as determined by simultaneous intracellular and extracellular measurements.</a> Journal of Neurophysiology. 84 (1), 401-414 (2000).</li>
<li>Jiang, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((TaiNi%3A+Maximizing+research+output+whilst+improving+animals%27+welfare+in+neurophysiology+experiments%5BTitle%5D)+AND+%22Scientific+Reports%22%5BJournal%5D)">TaiNi: Maximizing research output whilst improving animals' welfare in neurophysiology experiments.</a> Scientific Reports. 7 (1), 8086(2017).</li>
<li>Gao, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+cortico-cerebellar+loop+for+motor+planning%5BTitle%5D)+AND+%22Nature%22%5BJournal%5D)">A cortico-cerebellar loop for motor planning.</a> Nature. 563 (7729), 113(2018).</li>
<li>Neumann, A. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Involvement+of+fast-spiking+cells+in+ictal+sequences+during+spontaneous+seizures+in+rats+with+chronic+temporal+lobe+epilepsy%5BTitle%5D)+AND+%22Brain%22%5BJournal%5D)">Involvement of fast-spiking cells in ictal sequences during spontaneous seizures in rats with chronic temporal lobe epilepsy.</a> Brain. 140 (9), 2355-2369 (2017).</li>
<li>Gothard, K. M., Skaggs, W. E., Moore, K. M., McNaughton, B. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Binding+of+hippocampal+CA1+neural+activity+to+multiple+reference+frames+in+a+landmark-based+navigation+task%5BTitle%5D)+AND+%22Journal+of+Neuroscience%22%5BJournal%5D)">Binding of hippocampal CA1 neural activity to multiple reference frames in a landmark-based navigation task.</a> Journal of Neuroscience. 16 (2), 823-835 (1996).</li>
<li>McNaughton, B. L. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aMcNaughton%2C+BL+%22Google+Patents%22">Google Patents</a>. , (1999).</li>
<li>Wilber, A. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Cortical+connectivity+maps+reveal+anatomically+distinct+areas+in+the+parietal+cortex+of+the+rat%5BTitle%5D)+AND+%22Frontiers+in+Neural+Circuits%22%5BJournal%5D)">Cortical connectivity maps reveal anatomically distinct areas in the parietal cortex of the rat.</a> Frontiers in Neural Circuits. 8, 146(2015).</li>
<li>Mashhoori, A., Hashemnia, S., McNaughton, B. L., Euston, D. R., Gruber, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Rat+anterior+cingulate+cortex+recalls+features+of+remote+reward+locations+after+disfavoured+reinforcements%5BTitle%5D)+AND+%22Elife%22%5BJournal%5D)">Rat anterior cingulate cortex recalls features of remote reward locations after disfavoured reinforcements.</a> Elife. 7, 29793(2018).</li>
<li>Luczak, A., McNaughton, B. L., Harris, K. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Packet-based+communication+in+the+cortex%5BTitle%5D)+AND+%22Nature+Reviews+Neuroscience%22%5BJournal%5D)">Packet-based communication in the cortex.</a> Nature Reviews Neuroscience. , (2015).</li>
<li>Luczak, A. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aLuczak%2C+A+%22Analysis+and+Modeling+of+Coordinated+Multi-neuronal+Activity%22">Analysis and Modeling of Coordinated Multi-neuronal Activity</a>. , Springer. 163-182 (2015).</li>
</ol>

Authors do not have any conflict of interests related to this work.

The protocol described here, shows how to use a standard neurophysiological recording system to perform closed-loop stimulation. This protocol allows neuroscientists with limited expertise in computer science to rapidly implement a variety of closed-loop experiments with little cost. Such experiments are often necessary to study causal interactions in the brain.
After preparing an animal and installing the software (Steps 1 &amp; 2), the closed-loop experiment consists of two separate stages. ...

The goal of this protocol is to demonstrate how to implement closed-loop stimulation in neurophysiological experiments. The typical setup for closed-loop experiments in neuroscience involves triggering stimuli based on the online readout of neuronal activity. This, in turn, causes modifications in the brain activity, thus closing the feedback loop1,2. Such closed-loop experiments provide multiple benefits over standard open-loop setups, especially when combined with optogenetics, which allows researchers to target a specific subset of neurons. For example, Siegle and Wilson used closed-loop manipulations to study the role of theta oscillations in information processing3. They demonstrated that stimulating hippocampal neurons on the falling phase of theta oscillations had different effects on behavior than applying the same stimulation on the rising phase. Closed-loop experiments are also becoming increasingly important in preclinical studies. For instance, multiple epilepsy studies have shown that neuronal stimulation triggered on seizure onset is an effective approach to reduce the severity of seizures4,5,6. Moreover, systems for automated seizure detection and the contingent delivery of therapy7,8 showed significant benefits in epilepsy patients9,10,11,12. Another application area with rapid advancement of closed-loop methodologies is the control of neuroprosthetics with cortical brain&#8211;machine interfaces. This is because providing instantaneous feedback to users of prosthetic devices significantly improves accuracy and capability13.
In recent years, several labs have developed custom systems for the simultaneous electrical recording of neuronal activity and delivery of stimuli in a closed-loop system14,15,16,17,18. Although many of those setups have impressive characteristics, it is not always easy to implement them in other labs. This is because the systems often demand experienced technicians to assemble the required electronics and other necessary hardware and software components.
Therefore, in order to facilitate the adoption of closed-loop experiments in neuroscience research, this paper provides a protocol and Matlab code to convert an open-loop electrophysiological recording setup19,20,21,22 into a closed-loop system2,6,23. This protocol is designed to work with the Digital Lynx recording hardware, a popular laboratory system for neuronal population recordings. A typical experiment consists of the following: 1) Recording 5-20 minutes of spiking data; 2) Spike sorting to create neuronal templates; 3) Using these templates to perform online detection of neural activity patterns; and 4) Triggering stimulation or experimental events when user-specified patterns are detected.

<table><tbody><tr><td>Baytril</td><td>Bayer, Mississauga, CA</td><td>DIN 02169428</td><td>antibiotic; 50 mg/mL</td></tr><tr><td>Cheetah 6.4</td><td>NeuraLynx, Tucson, AZ</td><td>6.4.0.beta</td><td>Software interfaces for data acquisition&amp;nbsp;</td></tr><tr><td>Digital Lynx 4SX</td><td>NeuraLynx, Tucson, AZ</td><td>4SX</td><td>recording equipment</td></tr><tr><td>Headstage transmitter</td><td>TBSI</td><td>B10-3163-GK</td><td>transmits the neural signal to the receiver</td></tr><tr><td>Isoflurane</td><td>Fresenius Kabi, Toronto, CA</td><td>DIN 02237518</td><td>inhalation anesthetic</td></tr><tr><td>Jet Denture Powder &amp;amp; Liqud</td><td>Lang Dental, Wheeling, US</td><td>1230</td><td>dental acrylic</td></tr><tr><td>Lacri-Lube</td><td>Allergan, Markham, CA</td><td>DIN 00210889</td><td>eye ointment</td></tr><tr><td>Lido-2</td><td>Rafter 8, Calgary</td><td>DIN 00654639</td><td>local anesthetic; 20 mg/mL</td></tr><tr><td>Matlab</td><td>Mathworks</td><td>R2018b</td><td>software for signal processing and triggering external events</td></tr><tr><td>Metacam</td><td>Boehringer, Ingelheim, DE</td><td>DIN 02240463</td><td>analgesic; 5 mg/mL</td></tr><tr><td>Netcom</td><td>NeuraLynx</td><td>v1</td><td>Application Programming Interface (API) that communicates with Cheetah</td></tr><tr><td>Silicone probe</td><td>Cambridge Neurotech</td><td>ASSY-156-DBC2</td><td>implanted device</td></tr><tr><td>SpikeSort 3D&amp;nbsp;</td><td>NeuraLynx, Tucson, AZ</td><td>SS3D</td><td>spike waveform-to-cell classification tools</td></tr><tr><td>Wireless Radio Receiver</td><td>TBSI</td><td>911-1062-00</td><td>transmits the neural signal to the Digital Lynx</td></tr></tbody></table>

using neuron spiking activity to trigger closed-loop stimuli in neurophysiological experiments

Using Neuron Spiking Activity to Trigger Closed-Loop Stimuli in Neurophysiological Experiments

Closed-loop neurophysiological systems use patterns of neuronal activity to trigger stimuli, which in turn affect brain activity. Such closed-loop systems are already found in clinical applications, and are important tools for basic brain research. A particularly interesting recent development is the integration of closed-loop approaches with optogenetics, such that specific patterns of neuronal activity can trigger optical stimulation of selected neuronal groups. However, setting up an electrophysiological system for closed-loop experiments can be difficult. Here, a ready-to-apply Matlab code is provided for triggering stimuli based on the activity of single or multiple neurons. This sample code can be easily modified based on individual needs. For instance, it shows how to trigger sound stimuli and how to change it to trigger an external device connected to a PC serial port. The presented protocol is designed to work with a popular neuronal recording system for animal studies (Neuralynx). The implementation of closed-loop stimulation is demonstrated in an awake rat.

Fisher-Brown Norway rats born and raised on-site were habituated to handling for two weeks prior to the experiment. A recording drive was surgically implanted, similar to methods described previously28,29,30,31,32,33,34. The neuronal signals were recorded at 32 kHz with a digital acquisition...

This protocol demonstrates how to use an electrophysiological system for closed-loop stimulation triggered by neuronal activity patterns. Sample Matlab code that can be easily modified for different stimulation devices is also provided.

Closed-loop neurophysiological systems use patterns of neuronal activity to trigger stimuli, which in turn affect brain activity. Such closed-loop systems ...

using-neuron-spiking-activity-to-trigger-closed-loop-stimuli

Research

JoVE Journal

Neuroscience

We use a closed-loop fly-machine interface to investigate general principles in neuronal control.

An Experimental Platform to Study the Closed-loop Performance of Brain-machine Interfaces

Adult-born neurons expressing ChR2 can be manipulated in slice electrophysiological preparations in order to examine their contribution towards the function of olfactory neural circuits.

Using Affordable LED Arrays for Photo-Stimulation of Neurons

Understanding the function of the vertebrate central nervous system requires recordings from many neurons because cortical function arises on the level of populations of neurons. Here we describe an optical method to record suprathreshold neural activity with single-cell and single-spike resolution, dithered random-access scanning. This method records somatic fluorescence calcium signals from up to 100 neurons with high temporal resolution. A maximum-likelihood algorithm deconvolves the...

Optical Recording of Suprathreshold Neural Activity with Single-cell and Single-spike Resolution

This video demonstrates the operation of closed-loop stimulation in a rat with a surgically implanted device to record neural activity. Neuronal signals are first recorded and analyzed. Template waveforms are then uploaded, and parameters are defined to trigger closed-loop stimulation.

Triggering a Closed-Loop Stimulation by Neuron Spiking Activity

The recent development of neuroscience tools that combine genetics and optics, termed "optogenetics", enables control over neural circuit activity with an unprecedented level of spatial and temporal resolution. Here we provide a protocol for integrating in vivo recording with optogenetic manipulation of genetically-defined subsets of prefrontal cortical and subicular pyramidal neurons.

A Method for High Fidelity Optogenetic Control of Individual Pyramidal Neurons In vivo

To elucidate the complex transition from Local Field Potentials (LFPs) to spikes a suitable stimulator for light mechanical peripheral stimuli was built. As an application, the spiking activities recorded from somatosensory cortex were analyzed by a multi-objective optimization strategy. The results demonstrated that the proposed stimulator was able to deliver tactile stimuli with millisecond and millimeter precisions.

A Simple Stimulatory Device for Evoking Point-like Tactile Stimuli: A Searchlight for LFP to Spike Transitions

Closed-loop protocols are becoming increasingly widespread in modern day electrophysiology. We present a simple, versatile and inexpensive way to perform complex electrophysiological protocols in cortical pyramidal neurons in vitro, using a desktop computer and a digital acquisition board.

Real-time Electrophysiology: Using Closed-loop Protocols to Probe Neuronal Dynamics and Beyond

In this paper, an experimental framework to perform closed-loop experiments is presented, in which information processing (i.e., coding and decoding) and learning of neuronal assemblies are studied during the continuous interaction with a robotic body.

Closed-loop Neuro-robotic Experiments to Test Computational Properties of Neuronal Networks

This procedure performs long-lasting in vivo intracellular recordings from single neurons during physiologically relevant cerebral states and after complete abolition of ongoing electrical activities, resulting in an isoelectric brain state. The physiological constants of the animal are carefully monitored during the transition to the artificial comatose condition.

Induction of an Isoelectric Brain State to Investigate the Impact of Endogenous Synaptic Activity on Neuronal Excitability In Vivo

We present methods for the construction of electrodes to simultaneously record extracellular neural activity and release multiple neuroactive substances at the vicinity of the recording sites in awake mice. This technique allows the detailed analysis of putative local synaptic inputs to the neuron of interest.

Extracellular Recording of Neuronal Activity Combined with Microiontophoretic Application of Neuroactive Substances in Awake Mice

We present a method for the flexible chemical and multimodal stimulation and recording of simultaneous neural activity from many Caenorhabditis elegans worms. This method uses microfluidics, open-source hardware and software, and supervised automated data analysis to enable the measurement of neuronal phenomena such as adaptation, temporal inhibition, and stimulus crosstalk.

Automated Multimodal Stimulation and Simultaneous Neuronal Recording from Multiple Small Organisms

Learn closed-loop stimulation for studying causal brain interactions using awake rat recordings. This MATLAB-based protocol enables cost-effective real-time triggering of stimuli based on neuronal spiking activity.

Using Neuron Spiking Activity to Trigger Closed-Loop Stimuli in Neurophysiological Experiments

Explore More Videos