LSAMP (Louis Stokes Alliance for Minority Participation), Wehner, and The Crawford Foundation, the Kessler Foundation are all thanked for their support.

The research presented here was approved by the Institutional Review Board (IRB) committee of Montclair State University initiated in 2001 and updated yearly through 2023. All participants were treated within the ethical guidelines of the American Psychological Association. Typical safety procedures were followed. For example, we recruited nine adults from the general Montclair State University population using flyers and word of mouth. All subjects were screened in person employing TMS guidelines set forth by Wasserman19. Participants were compensated $25 for their enrollment in the study, and all subjects were treated within the standards put forth by the local Institutional Review Board (IRB) and in accordance with the Helsinki Declaration. Written informed consent was obtained from all participants and all subjects identified as being either Hispanic or African-American.
1. Background and 10/20 transfer
NOTE: For TMS, no additional equipment of any note will be needed (i.e., labs should easily have all these supplies).
<ol>
	<li>Participants
	<ol>
		<li>Before starting any procedures, be sure to obtain an IRB Committee Review. If this is an initial protocol, consult experienced researchers and prepare all forms such as Consent, Screening (Figure 1), and Side Effects (Figure 2) and practice their presentation. 
		NOTE: Forms should supplement and not substitute direct interviews with participants regarding safety.</li>
		<li>Ensure that all team members are trained in their roles. 
		NOTE: Training courses are available and almost all TMS laboratories freely share their best safety practices.</li>
		<li>Recruit participants through social media and flyers. 
		NOTE: Recruitment provides a monetary incentive and a brief description of risks.</li>
		<li>Administer the Screening Checklist before enrollment (Figure 1).</li>
		<li>Pay all participants for their participation ($25 in this study) and treat them in accordance with the guidelines of the Internal Review Board and the American Psychological Association.</li>
	</ol>
	</li>
	<li>Perform TMS using the parameters appropriate for the institution (see the discussion).</li>
	<li>Participant safety and comfort are critical so ask and monitor the participants both verbally and visually throughout the procedure. Be sure to look for nervousness, which can be the norm and, in some cases, leads to more difficult outcomes.</li>
</ol>
2.TMS equipment handling
<ol>
	<li>Ensure that the 70 mm figure-of-eight coil used for this experiment never reaches dangerous/shut-off temperatures. Keep backup coils ready in case they are needed as replacements.</li>
	<li>Use visual inspection (5/10 evoked Abductor Pollicis Brevis) or electromyography (EMG) to determine the motor threshold.</li>
</ol>
3. Motor threshold on non-braided hair
<ol>
	<li>Mark region CZ nasion/inion line and the midpoint taken using an erasable magic marker. Measure earlobe or pre-auricular points and mark those points as well.</li>
	<li>Using the right hemisphere line, go one-third down (from dorsal to ventral) and find the optimal location for the Abductor Pollicis Brevis (APB) activation. Trigger the TMS device via the coil trigger and the footswitch and disengage the safety from the front of the machine.</li>
	<li>Orient the TMS coil at 45&#176; for all searches and TMS deliveries.</li>
	<li>Use the dial on the front of the machine to start the stimulation output at 30% total machine output and increase in 2% increments until a movement is noted. Be sure to move the location with increasing stimulation intensity due to the careful interplay between coil movement and stimulation intensity.</li>
	<li>Once the site providing the maximum APB response is identified, determine the MT.</li>
	<li>To facilitate accurate placement before starting MT determination, mark the coil tip site on the swim cap and trace the entire anterior portion of the coil using a magic marker.</li>
	<li>For the visual inspection method, use the dial to start at 20% of the machine&#39;s intensity ad increase to deliver approximately 20 pulses to identify the stimulation level that results in 5/10 (50%) APB responses. Move the dial based on increased or decreased finger movements. Once 5/10 responses have been obtained, record the intensity displayed in the machine as the individual&#39;s MT.</li>
	<li>For the (preferred) MEP method, place disposable electrodes on the APB and the tendon of the thumb and a ground (around the back of the wrist), and instead of using visual inspection, confirm that a positive MEP is observed on the recording unit.
	<ol>
		<li>Define a positive MEP response as an MEP with &#8805;50 &#181;V peak-to-peak amplitude.</li>
		<li>Similar to visual inspection, stimulate until 5/10 positive MEPs are observed. Ensure that the MEPs are greater than 50 &#181;V. Record the MT when 50% of the MEPs are above (and 50% below) 50 &#181;V.</li>
	</ol>
	</li>
</ol>
4. Sol
<ol>
	<li>Practice with different brushes, combs, and paints, as researchers feel differently about different implements. 
	NOTE: The length of time to perfect the technique varies based on experience. Although it is not essential to document participant hair20, we include them here (Figure 3).</li>
	<li>Be consistent in terms of criteria to braid. There are no universal standards regarding which individuals should be braided prior to TMS. However, be sure to state the intention of using a determinant such as hair texture prior to any study or clinical application.</li>
	<li>Describe the methods to the participant and use photographs during consenting. Because valuing the participant should be a priority, use images and describe the braiding as part of the technique. 
	NOTE: One potential inducement (i.e., compensation) is the inclusion of braiding the entire head following the experiment.</li>
	<li>Know the target points before braiding begins.</li>
	<li>Transfer 10/20 coordinates (motor-related target points) to the scalp to provide target braiding points. To achieve this with a standard ERP/EEG cap, load a typical gel syringe and blunt needle with 1-5 mm of Green Florescent Paint (GFP). Apply the cap and, at the target points, insert the syringe as if applying gel and dab ~0.05 mm of GFP (Figure 4A - E). 
	NOTE: The amount of GFP will vary depending on the number of electrodes that need marking.</li>
	<li>Let the points dry for at least 2 min.</li>
	<li>Starting from the marked point on the head, pull the hair away. Ensure a clear patch of skin is seen around the mark. Try to clear the area of hair with fingers or a pick.</li>
	<li>Before starting, visualize first. To make 6-8 cornrows that will end up looking like a cartoon sun with the target point in the middle, make each braid, thinking of a clock face: cornrow 6 o&#39;clock first, then cornrow 12 o&#39;clock, and then cornrow 8 and 10 o&#39;clock. End with cornrowing 2 and 4 o&#39;clock. This will result in six cornrows.</li>
	<li>If eight cornrows are needed, start with 6 o&#39;clock and 12 o&#39;clock; then, cornrow 9 o&#39;clock, between 7 and 8 o&#39;clock, and between 10 and 11 o&#39;clock. Finalize with all missing rows. 
	NOTE: The main difference between cornrowing and braiding is that you will keep adding hair to your initial &#39;clump&#39;. You will &#39;adhere&#39; the braid to the scalp, thus reducing the height and awkwardness of the brain. Visualize this before starting cornrowing.</li>
	<li>To initiate the first conrow, from any side of the marked point, part a small section. Try to estimate an amount of hair that would be 1/8 or 1/6 of the hair needed to cornrow. This should be a small amount that is easy to manipulate-the initial clump.</li>
	<li>Use both hands to divide this initial clump into three sections. Make the sections equal in terms of the amount of hair.</li>
	<li>With the left section in the left hand, and the right section in the right hand, hold down the middle section with either, one, or both index fingers.</li>
	<li>If done correctly, the right section is now in the middle and what was the middle section is now on the right.</li>
	<li>Take the leftmost section and lift it. Put it in between the middle and right sections. If you did it correctly, this section is in the middle and the section that was in the middle is now on the left.</li>
	<li>Now take the right section and repeat step 2.6 while adding some new, additional hair from the scalp that is under the piece. 
	NOTE: Adding the hair will feel like a sweeping motion. This is what will make cornrows rather than braids.</li>
	<li>Continue grabbing one piece at a time while adding in hair going down the section.</li>
	<li>Continue cornrowing until the end of that clump of hair.</li>
	<li>Do this 6-8x to create a &#39;sun&#39; shape.</li>
</ol>
5. Motor threshold on braided hair
<ol>
	<li>Apply TMS now. Ensure that the coil surface at the maximal stimulation point lies flush now to the skin.</li>
	<li>Using a coil holder, mounting system, or by hand, press firmly against the skin with the plastic of the coil as per TMS norms. 
	NOTE: These methods are appropriate for a 70 mm figure-8 coil.</li>
	<li>Measure MEPs using electrodes and visual inspection. Targeted fingers should visibly move.</li>
	<li>Cornrow any additional target areas (e.g., Left Dorsal Lateral Prefrontal Cortex) in a similar manner. 
	NOTE: You can have multiple sites prepared simultaneously by using more than one trained braider.</li>
</ol>

Enhancing TMS Efficacy with Sol Braiding Technique in Diverse Populations

<ol><li>Yeung, A. W. K., Goto, T. K., Leung, W. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+changing+landscape+of+neuroscience+research%2C+2006-2015%3A+a+bibliometric+study%5BTitle%5D)+AND+%22Frontiers+in+Neuroscience%22%5BJournal%5D)">The changing landscape of neuroscience research, 2006-2015: a bibliometric study.</a> Frontiers in Neuroscience. 11, 120-120 (2017).</li>
<li>Choy, T., Baker, E., Stavropoulos, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Systemic+racism+in+EEG+research%3A+considerations+and+potential+solutions%5BTitle%5D)+AND+%22Affective+Science%22%5BJournal%5D)">Systemic racism in EEG research: considerations and potential solutions.</a> Affective Science. 3 (1), 14-20 (2021).</li>
<li>Assari, S., Moghani Lankarani, M., Caldwell, C. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Discrimination+increases+suicidal+ideation+in+black+adolescents+regardless+of+ethnicity+and+gender%5BTitle%5D)+AND+%22Behavioral+Sciences%22%5BJournal%5D)">Discrimination increases suicidal ideation in black adolescents regardless of ethnicity and gender.</a> Behavioral Sciences. 7 (4), Basel, Switzerland. 75(2017).</li>
<li>Bailey, R. K., Mokonogho, J., Kumar, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Racial+and+ethnic+differences+in+depression%3A+current+perspectives%5BTitle%5D)+AND+%22Neuropsychiatric+Disease+and+Treatment%22%5BJournal%5D)">Racial and ethnic differences in depression: current perspectives.</a> Neuropsychiatric Disease and Treatment. 15, 603-609 (2019).</li>
<li>Clark, L. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Increasing+diversity+in+clinical+trials%3A+overcoming+critical+barriers%5BTitle%5D)+AND+%22Current+Problems+in+Cardiology%22%5BJournal%5D)">Increasing diversity in clinical trials: overcoming critical barriers.</a> Current Problems in Cardiology. 44 (5), 148-172 (2019).</li>
<li>Etienne, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Novel+electrodes+for+reliable+EEG+recordings+on+coarse+and+curly+hair%5BTitle%5D)+AND+%22Annual+International+Conference+of+the+IEEE+Engineering+in+Medicine+and+Biology+Society%22%5BJournal%5D)">Novel electrodes for reliable EEG recordings on coarse and curly hair.</a> Annual International Conference of the IEEE Engineering in Medicine and Biology Society. , 6151-6154 (2020).</li>
<li>Rosen, A. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((TDCS+in+a+patient+with+dreadlocks%3A+Improvements+in+COVID-19+related+verbal+fluency+dysfunction%5BTitle%5D)+AND+%22Brain+Stimulation%22%5BJournal%5D)">TDCS in a patient with dreadlocks: Improvements in COVID-19 related verbal fluency dysfunction.</a> Brain Stimulation. 15 (1), 254-256 (2022).</li>
<li>Stokes, M. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Distance-adjusted+motor+threshold+for+transcranial+magnetic+stimulation%5BTitle%5D)+AND+%22Clinical+Neurophysiology%22%5BJournal%5D)">Distance-adjusted motor threshold for transcranial magnetic stimulation.</a> Clinical Neurophysiology. 118 (7), 1617-1625 (2007).</li>
<li>Wassermann, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Risk+and+safety+of+repetitive+transcranial+magnetic+stimulation%3A+report+and+suggested+guidelines+from+the+International+Workshop+on+the+Safety+of+Repetitive+Transcranial+Magnetic+Stimulation%2C+June+5-7%2C+1996%5BTitle%5D)+AND+%22Electoencephalography+and+Clincal+Neurophysiology%2FEvoked+Potentials+Section%22%5BJournal%5D)">Risk and safety of repetitive transcranial magnetic stimulation: report and suggested guidelines from the International Workshop on the Safety of Repetitive Transcranial Magnetic Stimulation, June 5-7, 1996.</a> Electoencephalography and Clincal Neurophysiology/Evoked Potentials Section. 108 (1), 1-16 (1998).</li>
<li>Bestmann, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Functional+modulation+of+primary+motor+cortex+during+action+selection%5BTitle%5D)+AND+%22Cortical+Connectivity.%3A+Brain+stimulation+for+assessing+and+modulating+cortical+connectivity+and+function%22%5BJournal%5D)">Functional modulation of primary motor cortex during action selection.</a> Cortical Connectivity.: Brain stimulation for assessing and modulating cortical connectivity and function. , Springer Berlin Heidelberg. Berline, Heidelberg. 183-205 (2012).</li>
<li>Bestmann, S., Krakauer, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+uses+and+interpretations+of+the+motor-evoked+potential+for+understanding+behaviour%5BTitle%5D)+AND+%22Experimental+Brain+Research%22%5BJournal%5D)">The uses and interpretations of the motor-evoked potential for understanding behaviour.</a> Experimental Brain Research. 233 (3), 679-689 (2015).</li>
<li>Chen, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+clinical+diagnostic+utility+of+transcranial+magnetic+stimulation%3A+Report+of+an+IFCN+committee%5BTitle%5D)+AND+%22Clinical+Neurophysiology%22%5BJournal%5D)">The clinical diagnostic utility of transcranial magnetic stimulation: Report of an IFCN committee.</a> Clinical Neurophysiology. 119 (3), 504-532 (2008).</li>
<li>Di Lazzaro, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Theta-burst+repetitive+transcranial+magnetic+stimulation+suppresses+specific+excitatory+circuits+in+the+human+motor+cortex%5BTitle%5D)+AND+%22The+Journal+of+Physiology%22%5BJournal%5D)">Theta-burst repetitive transcranial magnetic stimulation suppresses specific excitatory circuits in the human motor cortex.</a> The Journal of Physiology. 565, 945-950 (2005).</li>
<li>George, S., Duran, N., Norris, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+systematic+review+of+barriers+and+facilitators+to+minority+research+participation+among+African+Americans%2C+Latinos%2C+Asian+Americans%2C+and+Pacific+Islanders%5BTitle%5D)+AND+%22American+Journal+of+Public+Health%22%5BJournal%5D)">A systematic review of barriers and facilitators to minority research participation among African Americans, Latinos, Asian Americans, and Pacific Islanders.</a> American Journal of Public Health. 104 (2), e16-e31 (2014).</li>
<li>Rothwell, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Techniques+and+mechanisms+of+action+of+transcranial+stimulation+of+the+human+motor+cortex%5BTitle%5D)+AND+%22Journal+of+Neuroscience+Methods%22%5BJournal%5D)">Techniques and mechanisms of action of transcranial stimulation of the human motor cortex.</a> Journal of Neuroscience Methods. 74 (2), 113-122 (1997).</li>
<li>Terao, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Input-output+organization+in+the+hand+area+of+the+human+motor+cortex%5BTitle%5D)+AND+%22Electroencephalography+and+Clinical+Neurophysiology%2FElectromyography+and+Motor+Control%22%5BJournal%5D)">Input-output organization in the hand area of the human motor cortex.</a> Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control. 97 (6), 375-381 (1995).</li>
<li>Stokes, M. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Simple+metric+for+scaling+motor+threshold+based+on+scalp-cortex+distance%3A+application+to+studies+using+transcranial+magnetic+stimulation%5BTitle%5D)+AND+%22Journal+of+Neurophysiology%22%5BJournal%5D)">Simple metric for scaling motor threshold based on scalp-cortex distance: application to studies using transcranial magnetic stimulation.</a> Journal of Neurophysiology. 94 (6), 4520-4527 (2005).</li>
<li>Keenan, J. P., Archer, Q., Duran, G., Chavarria, K., Brenya, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Preventing+potential+racial+biasing+employing+transcranial+magnetic+stimulation%5BTitle%5D)+AND+%22Annual+Meeting+of+the+Eastern+Psychological+Association%22%5BJournal%5D)">Preventing potential racial biasing employing transcranial magnetic stimulation.</a> Annual Meeting of the Eastern Psychological Association. , Boston, MA. 73(2023).</li>
<li>Wassermann, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Risk+and+safety+of+repetitive+transcranial+magnetic+stimulation%3A+report+and+suggested+guidelines+from+the+International+Workshop+on+the+Safety+of+Repetitive+Transcranial+Magnetic+Stimulation%2C+June+5-7%2C+1996%5BTitle%5D)+AND+%22Electroencephalography+and+Clinical+Neurophysiology%22%5BJournal%5D)">Risk and safety of repetitive transcranial magnetic stimulation: report and suggested guidelines from the International Workshop on the Safety of Repetitive Transcranial Magnetic Stimulation, June 5-7, 1996.</a> Electroencephalography and Clinical Neurophysiology. 108 (1), 1-16 (1998).</li>
<li>Dela Mettrie, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Shape+variability+and+classification+of+human+hair%3A+a+worldwide+approach%5BTitle%5D)+AND+%22Human+Biology%22%5BJournal%5D)">Shape variability and classification of human hair: a worldwide approach.</a> Human Biology. 79 (3), 265-281 (2007).</li>
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</ol>

The authors have no conflicts of interest to declare.

Cornrows should not interfere with the angle (e.g., 45&#176;) of the TMS coil. If they do, one of the cornrows may need to be redone to alleviate this issue. If done correctly, MEPs should be consistent (Figure 6).
By utilizing the characteristics of curly or coarse hair, this method of braiding maintains the integrity of the TMS signal. In this study, we were able to significantly increase the MEP size and found an increased trend for consistency. These data have...

Neuroscience research, by its very nature, involves paradigm shifts and innovations for understanding brain function, neurological disabilities, and psychiatric disorders1. Despite much progress, the discipline of neuroscience has fallen short in some aspects. For example, there exist racial disparities, both in the number of researchers, but also in the representation of subjects and patients in research. Numerous underrepresented persons from minority groups are absent from experiments and clinical studies2. Only 5 publications out of 81 peer-reviewed scalp-based EEG articles from September to October 2019 specifically indicated having a sample that included minoritized individuals. Furthermore, recent studies demonstrated that individuals from underrepresented minority groups were often misdiagnosed or failed to trust the researchers. Assari et al. found that the healthcare community, specifically half of White medical students and residents, believed that African Americans have thicker skin than Whites, which influenced their medical judgment and treatment strategies3,4. Owing to the absence of data from minority participants, research findings are less generalizable and show disparities for minority populations. To ensure that the trial population is representative of the patients who will use the medication or medicinal product and that the results are generalizable, clinical trials must include a diverse group of participants5.
Of interest to scalp-based neuroscience is the distinct shape, thickness, styling, and density that is often seen in underrepresented minority hair. The follicle shape, for example, is one feature that makes African hair distinctive. African hair comes from smaller, more elliptical, and flat follicles while Caucasian and Asian hair follicles are more circular and large6. When minorities wash their hair, it curls, causing difficulties for researchers in their experiments. Minority groups are sometimes advised to wash and straighten their hair using hair products before coming in for scalp-based imaging, but doing so can have an impact on the accuracy of the data. Data are skewed because fewer participants of minority groups would volunteer and data from them might be discarded for being a lower quality. Moreover, due to their typical hairstyles (such as cornrows and braids), minoritized individuals are sometimes perceived as being difficult to recruit and retain2. Rosen et al. studied a man of African descent who wore dreadlocks, a style worn by underrepresented minoritized individuals, and presented with disfluency in spontaneous speech7. He wanted to receive treatment using scalp-based imaging since it had emerging evidence for efficacy and was tolerable.
One of the scalp-based imaging techniques that is used widely is transcranial magnetic stimulation (TMS). TMS is a surface-based imaging technique that is used in a non-invasive way to induce localized increases in brain activity. The ability to control neuronal activity in the human brain makes TMS a crucial tool for both experimental and therapeutic neuroscience8. To set standard safety recommendations, when represented as a percentage of the motor threshold (MT), TMS intensity provides a generalizable indicator of applied stimulation that may be used with any coil shape or kind of stimulator9. The motor evoked potential (MEPs) used in determining MT can also be a measure of cortico-excitability, which is elicited by TMS over the human motor cortex10,11,12,1,3,14,15,16. TMS is delivered to the motor cortex, which causes activation in the contra-lateral regions. Typically, regions of the hand are targeted as the stimulating target is not difficult to find on the motor cortex, and attaching electrodes or visually monitoring hand/digit responses is simple. The mechanisms governing motor output can be more fully comprehended using MEPs. Since MEPs are used to measure individual differences in MT, they are now a part of practically every TMS application. In general, it is dangerous to utilize TMS without gauging some aspect of MT. If TMS is delivered above the appropriate MT, seizures may result. If TMS is delivered below MT, results may be reduced or absent (i.e., targeted neurons may not be depolarized). Accurate MT reporting is also critical in comparing studies. For example, many of the studies in our lab use a 90% value, which tells other researchers that a 110% application may result in a greater effect.
Stokes et al. examined different distances between the target region and the stimulating coil and subsequently found a direct linear relationship between the distance and the individuals&#39; MT8,17. Therefore, minority groups, some with thicker natural hair might have less accurate MTs/MEP measurements. In a survey targeting the TMS community of published authors,we found when we asked open-ended questions such as &#34;does hair play a role in impedance?&#34; experts in the field replied: &#34;It increases thresholds. Moving hair aside, compressing it, etc.;&#34; We try to use gel to bridge that contact, but not a lot that can be done;&#34; &#34; Thick hair also makes contact difficult; same as above&#34;; &#34; More hair makes stimulation more difficult-especially if it prevents good scalp contact with the coil18. Dense hair growth makes it challenging to achieve contact between the TMS coil and the scalp, leaving minimal to no contact and impeding the signal. Previous research has shown that braiding thick, coarse hair reduces impedances in scalp-based imaging6. Using the characteristics of coarse or curly hair, Etienne et al. found that braiding a participant&#39;s hair into cornrows maintains signal integrity when using EEG.
We are introducing the Sol &#34;Sun&#34; method to offer a solution to manage the hair in underrepresented minorities. Due to the thickness and coarseness of their hair, we predicted that hair that is typically seen in underrepresented minorities will respond better to this procedure since it will preserve the hair (i.e., no shaving) and allow for long-term measurement. These methods are easy to teach, learn, and perform; require no additional equipment; do not increase safety risks; honor and respect the participants&#39; natural hair; and promote pride in the participant (and researchers) who may have felt previously discouraged by scalp-based techniques.

<table><tbody><tr><td>Android Samsung Tablet (for MEPs)</td><td></td><td></td><td></td></tr><tr><td>Cloth Measuring Tape</td><td></td><td></td><td></td></tr><tr><td>COVID Appropriate Sanitizers and Safety Masks/Gloves</td><td></td><td></td><td></td></tr><tr><td>Figure of 8 Copper TMS Coil</td><td></td><td></td><td></td></tr><tr><td>Lenovo T490 Laptop</td><td></td><td></td><td></td></tr><tr><td>Magstim 200 Single Pulse</td><td></td><td></td><td></td></tr><tr><td>Magstim Standard Coil Holder</td><td></td><td></td><td></td></tr><tr><td>Speedo Swim Caps</td><td></td><td></td><td></td></tr><tr><td>Testable.Org Account and Software</td><td></td><td></td><td></td></tr><tr><td>Trigno 2 Lead Sensor (for MEPs)</td><td></td><td></td><td></td></tr><tr><td>Trigno Base and Plot Software (for MEPs)</td><td></td><td></td><td></td></tr></tbody></table>

the sol braiding method for handling thick hair during transcranial magnetic stimulation: an address for potential bias in brain stimulation

Transcranial Magnetic Stimulation (TMS) is a technique that is frequently utilized in neuroscience for both therapeutic and research purposes. TMS offers critical medical services like treating major depression and is vital in almost every research facility. Because TMS relies on scalp placement, hair is thought to affect efficacy because it varies the distance to the target site. Further, it is presumed that the hair textures and length that are predominantly seen in minoritized persons might pose significant challenges to collecting high-quality data. Here, we present preliminary data demonstrating that TMS may be influenced by hair, particularly in historically underrepresented minoritized groups.
The Sol braiding approach is introduced here as an easy-to-learn, quick-to-implement technique that reduces variability in TMS. Compared across nine participants, it was found that the Sol method significantly increased motor evoked potential (MEP) strength and consistency (p &#60; 0.05). By removing the physical hair barrier that impedes direct coil-to-scalp contact, the Sol approach enhances TMS delivery. The MEP peak amplitude and the MEP area under the curve (AUC) were shown to increase as a result. While preliminary, these data are an important step in addressing diversity in neuroscience. These procedures are explained for non-braiding experts.

A TMS single-pulse device with a 70 mm figure-8 coil was employed for all stimulation sessions. MEPs were acquired using standard amplifiers and software installed on a local computer. All MEPs were obtained by attaching three electrodes targeting the Abductor Pollicis Brevis muscle (APB). The main hypothesis tested was that the Sol method would produce larger amplitudes and AUC compared to unbraided hair. To do this, we used ANOVAs using separate 2 x 9 (Pre/Post x Subject) tests. We pred...

Author Spotlight: Increasing TMS Accessibility Through Braiding Techniques for Diverse Hair Types

Hair type commonly seen in historically underrepresented minorities appears to interfere with transcranial magnetic stimulation (TMS). Here we describe a hair braiding method (The Sol Braiding Technique) that improves TMS.

The Sol Braiding Method for Handling Thick Hair During Transcranial Magnetic Stimulation: An Address for Potential Bias in Brain Stimulation

Transcranial Magnetic Stimulation (TMS) is a technique that is frequently utilized in neuroscience for both therapeutic and research purposes. TMS offers ...

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Research

JoVE Journal

Neuroscience

700 Views.  Montclair State University. De vraag die we ons stellen is of het vlechten van haar het eeuwenoude probleem in de neurowetenschappen kan oplossen van het omgaan met dik, krullend, dicht haar dat typerend is voor minderheden. Als toonaangevend TMS-lab hebben we de verantwoordelijkheid om inclusie te bevorderen. Hoewel ons onderzoek naar zelfbedrog en zelfbewustzijn wordt erkend, streven we er ook naar om manieren te verkennen om de diversiteit te vergroten.Uit ons enquêteonderzoek bleek dat deelnemers met dik haa...

Video: Auteur in de schijnwerpers: TMS-toegankelijkheid vergroten door middel van vlechttechnieken voor verschillende haartypes

Transcranial Magnetic Stimulation for Investigating Causal Brain-behavioral Relationships and their Time Course

Transcranial magnetic stimulation (TMS) is a safe, non-invasive brain stimulation technique that uses a strong electromagnet in order to temporarily disrupt information processing in a brain region, generating a short-lived &#8220;virtual lesion.&#8221; Stimulation that interferes with task performance indicates that the affected brain region is necessary to perform the task normally. In other words, unlike neuroimaging methods such as functional magnetic resonance imaging (fMRI) that indicate correlations between brain and behavior, TMS can be used to demonstrate causal brain-behavior relations. Furthermore, by varying the duration and onset of the virtual lesion, TMS can also reveal the time course of normal processing. As a result, TMS has become an important tool in cognitive neuroscience. Advantages of the technique over lesion-deficit studies include better spatial-temporal precision of the disruption effect, the ability to use participants as their own control subjects, and the accessibility of participants. Limitations include concurrent auditory and somatosensory stimulation that may influence task performance, limited access to structures more than a few centimeters from the surface of the scalp, and the relatively large space of free parameters that need to be optimized in order for the experiment to work. Experimental designs that give careful consideration to appropriate control conditions help to address these concerns. This article illustrates these issues with TMS results that investigate the spatial and temporal contributions of the left supramarginal gyrus (SMG) to reading.

Transcranial magnetic stimulation (TMS) is a technique for non-invasively disrupting neural information processing and measuring its effect on behavior. When TMS interferes with a task, it indicates that the stimulated brain region is necessary for normal task performance, allowing one to systematically relate brain regions to cognitive functions.

Transcranial magnetic stimulation (TMS) is a safe, non-invasive brain stimulation technique that uses a strong electromagnet in order to temporarily ...

Behavior

Non-Invasive Electrical Brain Stimulation Montages for Modulation of Human Motor Function

Non-invasive electrical brain stimulation (NEBS) is used to modulate brain function and behavior, both for research and clinical purposes. In particular, NEBS can be applied transcranially either as direct current stimulation (tDCS) or alternating current stimulation (tACS). These stimulation types exert time-, dose- and in the case of tDCS polarity-specific effects on motor function and skill learning in healthy subjects. Lately, tDCS has been used to augment the therapy of motor disabilities in patients with stroke or movement disorders. This article provides a step-by-step protocol for targeting the primary motor cortex with tDCS and transcranial random noise stimulation (tRNS), a specific form of tACS using an electrical current applied randomly within a pre-defined frequency range. The setup of two different stimulation montages is explained. In both montages the emitting electrode (the anode for tDCS) is placed on the primary motor cortex of interest. For unilateral motor cortex stimulation the receiving electrode is placed on the contralateral forehead while for bilateral motor cortex stimulation the receiving electrode is placed on the opposite primary motor cortex. The advantages and disadvantages of each montage for the modulation of cortical excitability and motor function including learning are discussed, as well as safety, tolerability and blinding aspects.

Non-invasive electrical brain stimulation can modulate cortical function and behavior, both for research and clinical purposes. This protocol describes different brain stimulation approaches for modulation of the human motor system.

Non-invasive electrical brain stimulation (NEBS) is used to modulate brain function and behavior, both for research and clinical purposes. In particular, ...

Treating Clinical Depression with Repetitive Deep Transcranial Magnetic Stimulation Using the Brainsway H1-coil

Repetitive transcranial magnetic stimulation (rTMS) is an emerging non-pharmacological approach to treating many brain-based disorders. rTMS uses electromagnetic coils to stimulate areas of the brain non-invasively. Deep transcranial magnetic stimulation (dTMS) with the Brainsway H1-coil system specifically is a type of rTMS indicated for treating patients with major depressive disorder (MDD) who are resistant to medication. The unique H1-coil design of this device is able to stimulate neuronal pathways that lie deeper in the targeted brain areas than those reached by conventional rTMS coils. dTMS is considered to be low-risk and well tolerated, making it a viable treatment option for people who have not responded to medication or psychotherapy trials for their depression.
Randomized, sham-control studies have demonstrated that dTMS produces significantly greater improvement in depressive symptoms than sham dTMS treatment in patients with major depression that has not responded to antidepressant medication. In this paper, we will review the methodology for treating major depression with dTMS using an H1-coil.

Here we present a protocol outlining the methodology for treatment of Major Depressive Disorder using the deep Transcranial Magnetic Stimulation (dTMS) system.

Repetitive transcranial magnetic stimulation (rTMS) is an emerging non-pharmacological approach to treating many brain-based disorders. rTMS uses ...

How to Use the H1 Deep Transcranial Magnetic Stimulation Coil for Conditions Other than Depression

Deep transcranial magnetic stimulation (dTMS) is a relatively new technique that uses different coils for the treatment of different neuropathologies. The coils are made of soft copper windings in multiple planes that lie adjacent to the skull. They are located within a special helmet so that their magnetic fields combine and improve depth penetration. The H1 dTMS coil is designed to stimulate bilateral prefrontal cortices with greater effective stimulation over the left than the right. By positioning the left side of the coil close to the left dorsolateral prefrontal cortex (DLPFC), the H1 coil was used in a multisite study, leading to FDA approval for treatment-resistant depression. In this same position, the H1 coil was also explored as a possible treatment for negative symptoms of schizophrenia, bipolar depression, and migraine. When moved to different positions over the subject's skull, the H1 coil was also explored as a possible treatment for other conditions. Such manipulation of the H1 coil was demonstrated for PTSD and alcohol dependence by positioning it over the medial prefrontal cortex (mPFC), for anxiety by positioning it over the right prefrontal cortex (rPFC), for auditory hallucinations and tinnitus by positioning it over the temporoparietal junction (TPJ), and for Parkinson's and fatigue from multiple sclerosis (MS) by positioning it over the motor cortex (MC) and PFC. Corresponding electrical field diagrams measured with an oscilloscope through a saline-filled head are included.

The H1 deep transcranial magnetic stimulation coil is FDA-cleared for the treatment of depression. We demonstrate how to utilize the H1 for other conditions, such as auditory hallucinations and PTSD, by moving the helmet to different locations over the subject's skull.

Deep transcranial magnetic stimulation (dTMS) is a relatively new technique that uses different coils for the treatment of different neuropathologies. The ...

Simultaneous Transcranial Alternating Current Stimulation and Functional Magnetic Resonance Imaging

Transcranial alternating current stimulation (tACS) is a promising tool for noninvasive investigation of brain oscillations. TACS employs frequency-specific stimulation of the human brain through current applied to the scalp with surface electrodes. Most current knowledge of the technique is based on behavioral studies; thus, combining the method with brain imaging holds potential to better understand the mechanisms of tACS. Because of electrical and susceptibility artifacts, combining tACS with brain imaging can be challenging, however, one brain imaging technique that is well suited to be applied simultaneously with tACS is functional magnetic resonance imaging (fMRI). In our lab, we have successfully combined tACS with simultaneous fMRI measurements to show that tACS effects are state, current, and frequency dependent, and that modulation of brain activity is not limited to the area directly below the electrodes. This article describes a safe and reliable setup for applying tACS simultaneously with visual task fMRI studies, which can lend to understanding oscillatory brain function as well as the effects of tACS on the brain.

Transcranial alternating current stimulation (tACS) is a promising tool for noninvasive investigation of brain oscillations, though its effects are not completely understood. This article describes a safe and reliable setup for applying tACS simultaneously with functional magnetic resonance imaging, which can increase understanding oscillatory brain function and effects of tACS.

Transcranial alternating current stimulation (tACS) is a promising tool for noninvasive investigation of brain oscillations. TACS employs ...

The Use of Magnetic Resonance Spectroscopy as a Tool for the Measurement of Bi-hemispheric Transcranial Electric Stimulation Effects on Primary Motor Cortex Metabolism

Transcranial direct current stimulation (tDCS) is a neuromodulation technique that has been increasingly used over the past decade in the treatment of neurological and psychiatric disorders such as stroke and depression. Yet, the mechanisms underlying its ability to modulate brain excitability to improve clinical symptoms remains poorly understood 33. To help improve this understanding, proton magnetic resonance spectroscopy (1H-MRS) can be used as it allows the in vivo quantification of brain metabolites such as &#947;-aminobutyric acid (GABA) and glutamate in a region-specific manner 41. In fact, a recent study demonstrated that 1H-MRS is indeed a powerful means to better understand the effects of tDCS on neurotransmitter concentration 34. This article aims to describe the complete protocol for combining tDCS (NeuroConn MR compatible stimulator) with 1H-MRS at 3 T using a MEGA-PRESS sequence. We will describe the impact of a protocol that has shown great promise for the treatment of motor dysfunctions after stroke, which consists of bilateral stimulation of primary motor cortices 27,30,31. Methodological factors to consider and possible modifications to the protocol are also discussed.

This article aims to describe a basic protocol for combining transcranial direct current stimulation (tDCS) with proton magnetic resonance spectroscopy (1H-MRS) measurements to investigate the effects of bilateral stimulation on primary motor cortex metabolism.

Transcranial direct current stimulation (tDCS) is a neuromodulation technique that has been increasingly used over the past decade in the treatment of ...

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 frequency and in turn modulate ongoing cortical oscillatory activity. This neurotool allows the establishment of a causal link between endogenous oscillatory activity and behavior. Most of the tACS studies have shown online effects of tACS. However, little is known about the underlying action mechanisms of this technique because of the AC-induced artifacts on Electroencephalography (EEG) signals. Here we show a unique approach to investigate online physiological frequency-specific effects of tACS of the primary motor cortex (M1) by using single pulse Transcranial Magnetic Stimulation (TMS) to probe cortical excitability changes. In our setup, the TMS coil is placed over the tACS electrode while Motor Evoked Potentials (MEPs) are collected to test the effects of the ongoing M1-tACS. So far, this approach has mainly been used to study the visual and motor systems. However, the current tACS-TMS setup can pave the way for future investigations of cognitive functions. Therefore, we provide a step-by-step manual and video guidelines for the procedure.

Transcranial Alternating Current Stimulation (tACS) allows the modulation of cortical excitability in a frequency-specific fashion. Here we show a unique approach which combines online tACS with single pulse Transcranial Magnetic Stimulation (TMS) in order to "probe" cortical excitability by means of Motor Evoked Potentials.

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

Measuring and Manipulating Functionally Specific Neural Pathways in the Human Motor System with Transcranial Magnetic Stimulation

Understanding interactions between brain areas is important for the study of goal-directed behavior. Functional neuroimaging of brain connectivity has provided important insights into fundamental processes of the brain like cognition, learning, and motor control. However, this approach cannot provide causal evidence for the involvement of brain areas of interest. Transcranial magnetic stimulation (TMS) is a powerful, noninvasive tool for studying the human brain that can overcome this limitation by transiently modifying brain activity. Here, we highlight recent advances using a paired-pulse, dual-site TMS method with two coils that causally probes cortico-cortical interactions in the human motor system during different task contexts. Additionally, we describe a dual-site TMS protocol based on cortical paired associative stimulation (cPAS) that transiently enhances synaptic efficiency in two interconnected brain areas by applying repeated pairs of cortical stimuli with two coils. These methods can provide a better understanding of the mechanisms underlying cognitive-motor function as well as a new perspective on manipulating specific neural pathways in a targeted fashion to modulate brain circuits and improve behavior. This approach may prove to be an effective tool to develop more sophisticated models of brain-behavior relations and improve diagnosis and treatment of many neurological and psychiatric disorders.

This article describes new approaches to measure and strengthen functionally specific neural pathways with transcranial magnetic stimulation. These advanced noninvasive brain stimulation methodologies can provide new opportunities for the understanding of brain-behavior relations and development of new therapies to treat brain disorders.

Understanding interactions between brain areas is important for the study of goal-directed behavior. Functional neuroimaging of brain connectivity has ...

Conventional and Threshold-Tracking Transcranial Magnetic Stimulation Tests for Single-handed Operation

Most single-pulse transcranial magnetic stimulation (TMS) parameters (e.g., motor threshold, stimulus-response function, cortical silent period) are used to examine corticospinal excitability. Paired-pulse TMS paradigms (e.g., short- and long-interval intracortical inhibition (SICI/LICI), short-interval intracortical facilitation (SICF), and short- and long-latency afferent inhibition (SAI/LAI)) provide information about intracortical inhibitory and facilitatory networks. This has long been done by the conventional TMS method of measuring changes in the size of the motor-evoked potentials (MEPs) in response to stimuli of constant intensity. An alternative threshold-tracking approach has recently been introduced whereby the stimulus intensity for a target amplitude is tracked. The diagnostic utility of threshold-tracking SICI in amyotrophic lateral sclerosis (ALS) has been shown in previous studies. However, threshold-tracking TMS has only been used in a few centers, in part due to the lack of readily available software but also perhaps due to uncertainty over its relationship to conventional single- and paired-pulse TMS measurements.
A menu-driven suite of semi-automatic programs has been developed to facilitate the broader use of threshold-tracking TMS techniques and to enable direct comparisons with conventional amplitude measurements. These have been designed to control three types of magnetic stimulators and allow recording by a single operator of the common single- and paired-pulse TMS protocols.
This paper shows how to record a number of single- and paired-pulse TMS protocols on healthy subjects and analyze the recordings. These TMS protocols are fast and easy to perform and can provide useful biomarkers in different neurological disorders, particularly neurodegenerative diseases such as ALS.

We present a suite of standardized single- and paired-pulse transcranial magnetic stimulation (TMS) recording protocols, with options for conventional amplitude measurements and threshold-tracking. This program can control three different types of magnetic stimulators and is designed to enable all tests to be performed conveniently by a single operator.

Most single-pulse transcranial magnetic stimulation (TMS) parameters (e.g., motor threshold, stimulus-response function, cortical silent period) are used ...

Combined Peripheral Nerve Stimulation and Controllable Pulse Parameter TMS

Combined Peripheral Nerve Stimulation and Controllable Pulse Parameter Transcranial Magnetic Stimulation to Probe Sensorimotor Control and Learning

Skilled motor ability depends on efficiently integrating sensory afference into the appropriate motor commands. Afferent inhibition provides a valuable tool to probe the procedural and declarative influence over sensorimotor integration during skilled motor actions. This manuscript describes the methodology and contributions of short-latency afferent inhibition (SAI) for understanding sensorimotor integration. SAI quantifies the effect of a convergent afferent volley on the corticospinal motor output evoked by transcranial magnetic stimulation (TMS). The afferent volley is triggered by the electrical stimulation of a peripheral nerve. The TMS stimulus is delivered to a location over the primary motor cortex that elicits a reliable motor-evoked response in a muscle served by that afferent nerve. The extent of inhibition in the motor-evoked response reflects the magnitude of the afferent volley converging on the motor cortex and involves central GABAergic and cholinergic contributions. The cholinergic involvement in SAI makes SAI a possible marker of declarative-procedural interactions in sensorimotor performance and learning. More recently, studies have begun manipulating the TMS current direction in SAI to tease apart the functional significance of distinct sensorimotor circuits in the primary motor cortex for skilled motor actions. The ability to control additional pulse parameters (e.g., the pulse width) with state-of-the-art controllable pulse parameter TMS (cTMS) has enhanced the selectivity of the sensorimotor circuits probed by the TMS stimulus and provided an opportunity to create more refined models of sensorimotor control and learning. Therefore, the current manuscript focuses on SAI assessment using cTMS. However, the principles outlined here also apply to SAI assessed using conventional fixed pulse width TMS stimulators and other forms of afferent inhibition, such as long-latency afferent inhibition (LAI).

Author Spotlight: Combined Peripheral Nerve Stimulation and Controllable Pulse Parameter Transcranial Magnetic Stimulation to Probe Sensorimotor Control and Learning  

Short-latency afferent inhibition (SAI) is a transcranial magnetic stimulation protocol to probe sensorimotor integration. This article describes how SAI can be used to study the convergent sensorimotor loops in the motor cortex during sensorimotor behavior.

Skilled motor ability depends on efficiently integrating sensory afference into the appropriate motor commands. Afferent inhibition provides a valuable ...

The Sol Braiding Method for Handling Thick Hair During Transcranial Magnetic Stimulation: An Address for Potential Bias in Brain Stimulation

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