Name: non-invasive modulation and robotic mapping of motor cortex in the developing brain
Uploaded: 2019-07-01T12:30:00
Description: Watch this Scientific Journal Video about Non-Invasive Modulation and Robotic Mapping of Motor Cortex in the Developing Brain at JoVE.com

This study was supported by the Canadian Institutes of Health Research.

All the methods described in this protocol have been approved by Conjoint Health Research Ethics Board, University of Calgary (REB16-2474). The protocol is described in Figure 1.
1. Non-invasive brain stimulation contraindications
<ol>
	<li>Screen all participants for contraindications for TMS15 and tDCS1 prior to recruitment.</li>
</ol>
2. Transcranial magnetic stimulation motor mapping
<ol>
	<li>Preparing...

<ol>
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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=Facilitation+of+implicit+motor+learning+by+weak+transcranial+direct+current+stimulation+of+the+primary+motor+cortex+in+the+human.">Facilitation of implicit motor learning by weak transcranial direct current stimulation of the primary motor cortex in the human.</a> Journal of Cognitive Neuroscience. 15 (4), 619-626 (2003).</li><li>Oskoui, M., Coutinho, F., Dykeman, J., Jett&#233;, N., Pringsheim, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+update+on+the+prevalence+of+cerebral+palsy:+a+systematic+review+and+meta-analysis.">An update on the prevalence of cerebral palsy: a systematic review and meta-analysis.</a> Developmental Medicine &amp; Child Neurology. 55 (6), 509-519 (2013).</li><li>Zewdie, E., Kirton, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TMS+Basics:+Single+and+Paired+Pulse+Neurophysiology.">TMS Basics: Single and Paired Pulse Neurophysiology.</a> Pediatric Brain Stimulation: Mapping and Modulating the Developing Brain. , 475 (2016).</li><li>Nudo, R. 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J., Rosen, A., Gorman, C., Bikson, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dosage+considerations+for+transcranial+direct+current+stimulation+in+children:+a+computational+modeling+study.">Dosage considerations for transcranial direct current stimulation in children: a computational modeling study.</a> PloS One. 8 (9), e76112 (2013).</li><li>Ciechanski, P., Carlson, H. L., Yu, S. S., Kirton, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modeling+Transcranial+Direct-Current+Stimulation-Induced+Electric+Fields+in+Children+and+Adults.">Modeling Transcranial Direct-Current Stimulation-Induced Electric Fields in Children and Adults.</a> Frontiers in Human Neuroscience. 12, 268 (2018).</li><li>Ciechanski, P., Kirton, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transcranial+Direct-Current+Stimulation+(tDCS):+Principles+and+Emerging+Applications+in+Children.">Transcranial Direct-Current Stimulation (tDCS): Principles and Emerging Applications in Children.</a> Pediatric Brain Stimulation: Mapping and Modulating the Developing Brain. , 475 (2016).</li><li>Kirton, 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=Transcranial+direct+current+stimulation+for+children+with+perinatal+stroke+and+hemiparesis.">Transcranial direct current stimulation for children with perinatal stroke and hemiparesis.</a> Neurology. 88 (3), 259-267 (2017).</li><li>Cole, L., 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=Effects+of+High-Definition+and+Conventional+Transcranial+Direct-Current+Stimulation+on+Motor+Learning+in+Children.">Effects of High-Definition and Conventional Transcranial Direct-Current Stimulation on Motor Learning in Children.</a> Front Neurosci. , (2018).</li><li>Rossi, S., Hallett, M., Rossini, P. M., Pascual-Leone, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Screening+questionnaire+before+TMS:+an+update.">Screening questionnaire before TMS: an update.</a> Clinical Neurophysiology. 122 (8), 1686 (2011).</li><li>Villamar, M. F., Volz, M. S., Bikson, M., Datta, A., Dasilva, A. F., Fregni, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Technique+and+considerations+in+the+use+of+4x1+ring+high-definition+transcranial+direct+current+stimulation+(HD-tDCS).">Technique and considerations in the use of 4x1 ring high-definition transcranial direct current stimulation (HD-tDCS).</a> Journal of Visualized Experiments. (77), e50309 (2013).</li><li>Yousry, T. 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=Localization+of+the+motor+hand+area+to+a+knob+on+the+precentral+gyrus.+A+new+landmark.">Localization of the motor hand area to a knob on the precentral gyrus. A new landmark.</a> Brain. 120 (Pt 1), 141-157 (1997).</li><li>Garvey, M. A., Mall, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transcranial+magnetic+stimulation+in+children.">Transcranial magnetic stimulation in children.</a> Clinical Neurophysiology. 119 (5), 973-984 (2008).</li><li>Borckardt, J. J., 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=A+pilot+study+investigating+the+effects+of+fast+left+prefrontal+rTMS+on+chronic+neuropathic+pain.">A pilot study investigating the effects of fast left prefrontal rTMS on chronic neuropathic pain.</a> Pain Medicine (Malden, Mass.). 10 (5), 840-849 (2009).</li><li>Villamar, M. F., 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=Focal+modulation+of+the+primary+motor+cortex+in+fibromyalgia+using+4&#215;1-ring+high-definition+transcranial+direct+current+stimulation+(HD-tDCS):+immediate+and+delayed+analgesic+effects+of+cathodal+and+anodal+stimulation.">Focal modulation of the primary motor cortex in fibromyalgia using 4&#215;1-ring high-definition transcranial direct current stimulation (HD-tDCS): immediate and delayed analgesic effects of cathodal and anodal stimulation.</a> The Journal of Pain. 14 (4), 371-383 (2013).</li><li>Ciechanski, P., Kirton, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transcranial+Direct-Current+Stimulation+Can+Enhance+Motor+Learning+in+Children.">Transcranial Direct-Current Stimulation Can Enhance Motor Learning in Children.</a> Cerebral Cortex. 27 (5), 2758-2767 (2017).</li><li>Kirton, A., Andersen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brain+stimulation+and+constraint+for+hemiparesis+after+perinatal+stroke:+The+PLASTIC+CHAMPS+trial.">Brain stimulation and constraint for hemiparesis after perinatal stroke: The PLASTIC CHAMPS trial.</a> European Journal of Paediatric Neurology. 19 (S1), S10 (2015).</li><li>Ginhoux, R., 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=A+custom+robot+for+Transcranial+Magnetic+Stimulation:+First+assessment+on+healthy+subjects.">A custom robot for Transcranial Magnetic Stimulation: First assessment on healthy subjects.</a> 2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). , 5352-5355 (2013).</li><li>Grau, C., 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=Conscious+brain-to-brain+communication+in+humans+using+non-invasive+technologies.">Conscious brain-to-brain communication in humans using non-invasive technologies.</a> PloS One. 9 (8), e105225 (2014).</li><li>Julkunen, P. <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+estimating+cortical+motor+representation+size+and+location+in+navigated+transcranial+magnetic+stimulation.">Methods for estimating cortical motor representation size and location in navigated transcranial magnetic stimulation.</a> Journal of Neuroscience Methods. 232, 125-133 (2014).</li><li>van de Ruit, M., Perenboom, M. J., Grey, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TMS+brain+mapping+in+less+than+two+minutes.">TMS brain mapping in less than two minutes.</a> Brain Stimulation. 8 (2), 231-239 (2015).</li><li>Dundas, J. E., Thickbroom, G. W., Mastaglia, F. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perception+of+comfort+during+transcranial+DC+stimulation:+effect+of+NaCl+solution+concentration+applied+to+sponge+electrodes.">Perception of comfort during transcranial DC stimulation: effect of NaCl solution concentration applied to sponge electrodes.</a> Clinical Neurophysiology. 118 (5), 1166-1170 (2007).</li><li>Alam, M., Truong, D. 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TMS has also been explored in clinical pediatric populations, including perinatal stroke22 and cerebral palsy, where TMS motor maps were successfully created in children with cerebral palsy to explore mechanisms of interventional plasticity. Using an established protocol8, TMS motor maps were successfully collected in typically developing children, and are currently being collected in an ongoing multicenter clinical trial for children with perinatal stroke and hemiplegic ce...

Non-invasive brain stimulation can both measure and modulate human brain function1,2. The most common target has been the motor cortex, due in part to an immediate and measurable biological output (motor evoked potentials) but also the high prevalence of neurological diseases resulting in motor system dysfunction and disability. This large global burden of disease includes a high proportion of conditions affecting children such as cerebral palsy, the leading cause of lifelong disability affecting some 17 million persons worldwide3. Despite this clinical relevance and the diverse and increasing capacities of neurostimulation technologies, applications in the developing brain are only beginning to be defined4. Improved characterization of existing and emerging non-invasive brain stimulation methods in children are required to advance applications in the developing brain.
Transcranial magnetic stimulation (TMS) is a well-established neurophysiological tool being increasingly used for its non-invasive, painless, well-tolerated and safety profile in adults. TMS experience in children is relatively limited but steadily increasing. TMS delivers magnetic fields to induce regional activation of cortical neuronal populations in the brain with net outputs reflected in target muscle motor evoked potentials (MEP). Systematic application of single pulse TMS can define maps of the motor cortex in vivo. Seminal animal studies5 and emerging human TMS studies6 have shown how motor maps may help inform mechanisms of cortical neuroplasticity. Navigated motor mapping is a TMS technique that is used to map out the human motor cortex to interrogate functional cortical regions. Changes in motor map have been associated with plastic changes of the human motor system7. Recent advancements in robotic TMS technology have brought new opportunities to improve motor mapping efficiency and accuracy. Our group has recently demonstrated that robotic TMS motor mapping is feasible, efficient, and well tolerated in children8.
Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that can shift cortical excitability and modulate human behaviors. There has been a multitude of studies examining the effect of tDCS in adults (&#62;10,000 subjects) but less than 2% of studies have focused on the developing brain9. Translation of adult evidence to pediatrics applications is complex, and modified protocols are needed due to complex differences in children. For example, we and others have shown that children experience larger and stronger electric fields compared to adults10,11. Standardization of tDCS methods in children is important to ensure safe and consistent application, improve replication, and advance the field. Experience of motor learning modulation tDCS in children is limited but increasing12. Translational applications of tDCS to specific cerebral palsy populations are advancing towards late phase clinical trials13. Efforts toward more focal stimulation applied through high-definition tDCS (HD-tDCS) has only just been studied for the first time in children14. We demonstrated that HD-tDCS produces similar improvements in motor learning as conventional tDCS in healthy children14. Describing HD-tDCS methods will allow for replication and further applications of such protocols in children.

<table>
	<tbody>
		<tr>
			<td>1x1 SMARTscan Stimulator</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/1x1/tdcs/device</td>
			<td></td>
		</tr>
		<tr>
			<td>4x1 HD-tDCS Adaptor</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/hd-tdcs/4x1</td>
			<td></td>
		</tr>
		<tr>
			<td>Brainsight Neuronavigation</td>
			<td>Roge Resolution</td>
			<td>https://www.rogue-resolutions.com/catalogue/neuro-navigation/brainsight-tms-navigation/</td>
			<td></td>
		</tr>
		<tr>
			<td>Carbon Rubber Electrode</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/1x1/accessories/carbon-ruber-electrode</td>
			<td></td>
		</tr>
		<tr>
			<td>EASYpad Electrode</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/1x1/accessories/1x1-easypad</td>
			<td></td>
		</tr>
		<tr>
			<td>EASYstraps</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/1x1/accessories/1x1-easystrap</td>
			<td></td>
		</tr>
		<tr>
			<td>EMG Amplifier</td>
			<td>Bortec Biomedical</td>
			<td>http://www.bortec.ca/pages/amt_16.htm</td>
			<td></td>
		</tr>
		<tr>
			<td>HD1 Electrode Holder</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/hd-tdcs/accessories/hd1-holder</td>
			<td>Standard Base HD-Electrode Holder for High Definition tES (HD-tES)</td>
		</tr>
		<tr>
			<td>HD-Electrode</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/hd-tdcs/accessories/hd-electrode</td>
			<td>Sintered ring HD-Electrode.</td>
		</tr>
		<tr>
			<td>HD-Gel</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/hd-tdcs/accessories/hd-gel</td>
			<td>HD-GEL for High Definition tES (HD-tES)</td>
		</tr>
		<tr>
			<td>Micro 1401 Data Acquisition System</td>
			<td>Cambridge Electronics http://ced.co.uk/products/mic3in</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Purdue Pegboard</td>
			<td>Lafayette Instrument Company</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Saline solution</td>
			<td>Baxter</td>
			<td>http://www.baxter.ca/en/products-expertise/iv-solutions-premixed-drugs/products/iv-solutions.page</td>
			<td></td>
		</tr>
		<tr>
			<td>Soterix Medical HD-Cap</td>
			<td>Soterix Medical Inc.</td>
			<td>https://soterixmedical.com/research/hd-tdcs/accessories/hd-cap</td>
			<td></td>
		</tr>
		<tr>
			<td>TMS Robot</td>
			<td>Axilium Robotics</td>
			<td>http://www.axilumrobotics.com/en/</td>
			<td></td>
		</tr>
		<tr>
			<td>TMS Stimulator and Coil</td>
			<td>Magstim Inc</td>
			<td>https://www.magstim.com/neuromodulation/</td>
			<td></td>
		</tr>
	</tbody>
</table>

non-invasive modulation and robotic mapping of motor cortex in the developing brain

Mapping the motor cortex with transcranial magnetic stimulation (TMS) has potential to interrogate motor cortex physiology and plasticity but carries unique challenges in children. Similarly, transcranial direct current stimulation (tDCS) can improve motor learning in adults but has only recently been applied to children. The use of tDCS and emerging techniques like high&#8211;definition tDCS (HD-tDCS) require special methodological considerations in the developing brain. Robotic TMS motor mapping may confer unique advantages for mapping, particularly in the developing brain. Here, we aim to provide a practical, standardized approach for two integrated methods capable of simultaneously exploring motor cortex modulation and motor maps in children. First, we describe a protocol for robotic TMS motor mapping. Individualized, MRI-navigated 12x12 grids centered on the motor cortex guide a robot to administer single-pulse TMS. Mean motor evoked potential (MEP) amplitudes per grid point are used to generate 3D motor maps of individual hand muscles with outcomes including map area, volume, and center of gravity. Tools to measure safety and tolerability of both methods are also included. Second, we describe the application of both tDCS and HD-tDCS to modulate the motor cortex and motor learning. An experimental training paradigm and sample results are described. These methods will advance the application of non-invasive brain stimulation in children.

Using the methods presented here, we completed a randomized, sham-controlled interventional trial8. Right-handed children (n = 24, ages 12-18) with no contraindications for both types of non-invasive brain stimulation were recruited. Participants were specifically excluded in this study if on neuropsychotropic medication or if they were not na&#239;ve to tDCS. There were no dropouts.
Robotic TMS motor map...

Watch this Scientific Journal Video about Non-Invasive Modulation and Robotic Mapping of Motor Cortex in the Developing Brain at JoVE.com

Non-Invasive Modulation and Robotic Mapping of Motor Cortex in the Developing Brain

We demonstrate protocols for the modulation (tDCS, HD-tDCS) and mapping (robotic TMS) of the motor cortex in children.

Mapping the motor cortex with transcranial magnetic stimulation (TMS) has potential to interrogate motor cortex physiology and plasticity but carries ...

Our protocol involves using the first pediatric TMS robot in the world to map the motor cortex in healthy children and also in children who have had early brain injuries such as perinatal stroke. Protocol integrates MRI imaging with neuronavigation, which allows us to acquire maps with increased accuracy and precision, reduce mapping session times. It helps eliminate human error and it increases safety and tolerability for young patients.Motor mapping is not yet used for diagnostic or prognostic purposes, however, it is a novel technique that measures how the brain changes and rewires after either damage to the brain has occurred or after an intervention. Similar techniques with different targets can be used for language area mapping. Language and motor mapping can be important for pre-surgical planning.Begin by using the tabs in the neuronavigation software to reconstruct skin and full brain curvilinear. Select new, skin, and compute skin. Ensure the nose and top of the head are included.Then, select new and full brain curvilinear. Enclose the green selection box outside of the brain, but inside of the skull. Select compute curvilinear.Adjust the peel depth to 4.0 to 6.0 millimeters. Select configure landmarks. Place four landmarks at the tip of the nose, nasion, and the notches of both ears of the reconstructed skin.Name the landmarks corresponding to their anatomy. Select the target's tab to view the curvilinear brain. Select new and rectangular grid.Place uniform 12 by 12 coordinate grids with seven millimeter spacing on the surface of the reconstructed brain over the handknob of the motor cortex. Next, use the target positioning tool on the right to optimize the grid positioning for rotation, tilt, and curvature. Convert the grid points into trajectories that will guide the robot to position the TMS coil.Adjust the angle of the trajectory so they are 45 degrees to the longitudinal fissure or the brain. Use the snap tool to extrapolate and optimize the trajectories to the curvilinear brain. Finally, initialize and position the TMS robot arm and seat to welcome position and calibrate the force plate sensor using four sensor test.Begin by escorting the participant into the testing room and having them fill out a safety questionnaire. Then, seat the participant in the robot chair and adjust the backrest and neck rest. Ensure their feet are supported.Support the arms and hands with pillows during the mapping session. Clean the skin over the muscle of interest. Place silver silver chloride surface electrodes on both hands and forearms of the participant targeting four distal forelimb muscles.The belly of the first dorsal interosseous, abductor pollicis brevis, abductor digiti minimi, and the wrist extensor. Connect the amplifier to a data collecting computer with compatible EMG software. Next, surface electrodes to the electromyography, or EMG, amplifier and a data acquisition system, making sure that the ground electrode is connected as well.Co-register the four landmarks on the head of the participant using the landmark pointers and use the validation tab to ensure the participants head is properly registered. Then, select a grid point closest to the participant's handknob. Select the align to target button to align the TMS coil held by the robot to this target location.Select contact on. Monitor the contact quality using the contact force indicator and ensure the indicator is green or yellow. Instruct the participant not to move outside the scope of the robot arm.Ensure the participant's hand muscles are relaxed and remain still prior to contact. Select align and follow so the coil remains centered on the target if the participant moves. Use the TMS trigger button on the TMS machine to deliver five to 10 TMS pulses at an intensity between 40 to 60%maximum stimulator output.Lastly, determine the grid point that gives the largest and most consistent motor evoked potential for the left or right FDI muscle. Determine the resting motor threshold as the lowest intensity that produces and MEP of at least 50 microvolts in the FDI muscle in five out of 10 stimulation. Begin by delivering four single pulse TMS pulses at an interstimulus of one second and intensity of 120%RMT at the grid point closes to the hotspot.Then, repeat at the adjacent grid point. Continue sequentially in a linear fashion along responsive points until a non-responsive point is reached, which designates the first boarder region of the map. Then, continue mapping to establish the boarder points in all four directions of the rectangular grid.Record all MEPs from all muscles using the EMG software for offline analysis. After three to four grid points, select contact off and give the participant a break until they feel ready to continue. Next, use a hard copy version of the same grids to track the stimulation order for further analysis.Complete mapping using a robotic TMS. Finally, use a custom made coding script to generate 3D motor maps available by contacting the author. Calculate motor map area and volume using responsive trajectory sites.Calculate center of gravity as weighted average of the motor representations of each coordinate location. These results indicated that tDCS and HD-tDCS improved the rate of learning over five days of training. The active intervention groups had larger improvements in daily average left hand PPT score at day four and five compared to sham.This methodology has been replicated from a previous study and the data sets were combined. The replication data demonstrated similar results such that there was a significant increase in the rate of learning observed in the tDCS and HD-tDCS group compared to the sham group. Planning the procedure is as important as performing it.Grids and trajectories should be carefully overlaid on an MRI. If using brain templates, multiple samples should be taken from the participants head. This procedure can be completed pre-and post-intervention to answer resulting motor map change.Performing assessment following this procedure can indicate the relationship between motor map measures and function outcome. Using this protocol, researchers can learn how to generate motor maps accurately, timely, as well as safely in children using robotic TMS. Major challenge include guiding the robot and aligning it optimal its target areas.The trajectories must be accurately predetermined. Practicing coil alignment with multiple combinations of tilt and rotation parameters helps optimize coil trajectory design. None of the instruments are hazardous.It is important to constantly observe the robot while it is touching the participant's head as the robot will react to any head movements.

Research

JoVE Journal

Neuroscience

Functional Imaging of Auditory Cortex in Adult Cats using High-field fMRI

Current knowledge of sensory processing in the mammalian auditory system is mainly derived from electrophysiological studies in a variety of animal ...

Live Imaging of Mitosis in the Developing Mouse Embryonic Cortex

Although of short duration, mitosis is a complex and dynamic multi-step process fundamental for development of organs including the brain. In the ...

Non-invasive Parenchymal, Vascular and Metabolic High-frequency Ultrasound and Photoacoustic Rat Deep Brain Imaging

Photoacoustics and high frequency ultrasound stands out as powerful tools for neurobiological applications enabling high-resolution imaging on the central ...

Non-invasive Assessment of Changes in Corticomotoneuronal Transmission in Humans

The corticospinal pathway is the major pathway connecting the brain with the muscles and is therefore highly relevant for movement control and motor ...

Effects of Transcranial Alternating Current Stimulation on the Primary Motor Cortex by Online Combined Approach with Transcranial Magnetic Stimulation

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific ...

In Vivo Single-Molecule Tracking at the Drosophila Presynaptic Motor Nerve Terminal

In Vivo Single-Molecule Tracking at the Drosophila Presynaptic Motor Nerve Terminal

An increasing number of super-resolution microscopy techniques are helping to uncover the mechanisms that govern the nanoscale cellular world. ...

Combined Transcranial Magnetic Stimulation and Electroencephalography of the Dorsolateral Prefrontal Cortex

Transcranial magnetic stimulation (TMS) is a non-invasive method that produces neural excitation in the cortex by means of brief, time-varying magnetic ...

Evaluation of Hemisphere Lateralization with Bilateral Local Field Potential Recording in Secondary Motor Cortex of Mice

This article demonstrates complete, detailed procedures for both in vivo bilateral recording and analysis of local field potential (LFP) in the cortical ...

Translational Brain Mapping at the University of Rochester Medical Center: Preserving the Mind Through Personalized Brain Mapping

The Translational Brain Mapping Program at the University of Rochester is an interdisciplinary effort that integrates cognitive science, neurophysiology, ...

Laser-Induced Brain Injury in the Motor Cortex of Rats

A common technique for inducing stroke in experimental rodent models involves the transient (often denoted as MCAO-t) or permanent (designated as MCAO-p) ...