<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">
Hi Tasha,
<div class=""><br class="">
</div>
<div class="">Since you are referring to FieldTrip as a plug-in to Brainstorm, it is not clear to us whether you are using (possibly outdated) fieldtrip code that comes shipped with Brainstorm, or whether you have computed the spatial derivatives in ‘plain’
up-to-date FieldTrip. </div>
<div class=""><br class="">
</div>
<div class="">Hence, it is unclear what algorithm was used for the Laplacian, so it’s hard to comment about units to begin with. Also, since you are visualizing in Brainstorm, it’s Brainstorm that seems to interpret (and perhaps rescales) the numeric data and
adds a unit-label to the ERP’s y-axis, so perhaps it’s better to ask your question to François and his team.</div>
<div class=""><br class="">
</div>
<div class="">Best wishes,</div>
<div class="">Jan-Mathijs</div>
<div class=""><br class="">
</div>
<div class=""><br class="">
<div class="">
<div><br class="">
<blockquote type="cite" class="">
<div class="">On 14 May 2021, at 14:21, Natalie Poppa <<a href="mailto:Natalie.Poppa@UGent.be" class="">Natalie.Poppa@UGent.be</a>> wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
Greetings,</div>
<div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
<br class="">
</div>
<div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
I was using the Fieldtrip plug-in within Brainstorm to apply the Laplacian spline transformation to my ERPs. When I visualized ERPs within Brainstorm, they were scaled approximately between -150 to 150 (the units were labeled microvolts, but this must be a
mislabeling since it should be in V/m^2)... Anyway, when I export my ERPs, the values are 10^6 times smaller. Should I rescale them to match what I see when plotting in Brainstorm, or is V/m^2 expected to be a very small number?</div>
<div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
<br class="">
</div>
<div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
Thank you,</div>
<div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
<br class="">
</div>
<div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
Tasha<br class="">
</div>
<div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
<br class="">
</div>
<div id="Signature" class="">
<div class="">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">
Tasha Poppa, PhD</div>
<a href="https://urldefense.com/v3/__https://www.gheplab.ugent.be/__;!!HJOPV4FYYWzcc1jazlU!ttK8ahrzcSUY4iUWwWPoZYGkGuMlOC-18JEKvyZ6ABLnpcrAoKeL7joOyAefMsYEfPDB1wD8$" class="">https://www.gheplab.ugent.be/</a><br class="">
</div>
</div>
</div>
<span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">_______________________________________________</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">fieldtrip
mailing list</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<a href="https://mailman.science.ru.nl/mailman/listinfo/fieldtrip" style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">https://mailman.science.ru.nl/mailman/listinfo/fieldtrip</a><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<a href="https://urldefense.com/v3/__https://doi.org/10.1371/journal.pcbi.1002202__;!!HJOPV4FYYWzcc1jazlU!ttK8ahrzcSUY4iUWwWPoZYGkGuMlOC-18JEKvyZ6ABLnpcrAoKeL7joOyAefMsYEfAyw3S01$" style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">https://urldefense.com/v3/__https://doi.org/10.1371/journal.pcbi.1002202__;!!HJOPV4FYYWzcc1jazlU!ttK8ahrzcSUY4iUWwWPoZYGkGuMlOC-18JEKvyZ6ABLnpcrAoKeL7joOyAefMsYEfAyw3S01$</a><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class=""></span></div>
</blockquote>
</div>
<br class="">
</div>
</div>
</body>
</html>