<div dir="ltr"><div><div><div><div>Hello Pouneh Baniasad,<br><br></div>I had a similar issue some time ago, and found my solution within Fieldtrip, so I might be able to offer a bit of advice. <br><br>There is a function for in Fieldtrip that will (partially) allow you to simulate dipoles. It's called ft_dipolesimulation.m. <br><br>Unfortunately, in its current state, it only allows you to simulate 1 dipole. It does have quite a bit potential, however, since the function seems to be originally intended to work with multiple dipoles,
but in its current implementation, it will not actually cycle through
multiple dipoles and will crash if you give it more than 1.<br><br>The function will allow you to set frequency, phase, amplitude, sample rate, orientation vector etc. for the dipoles but I didn't test how that works for more than one dipole, since I used externally generated data as my dipole waveforms. <br><br>With only a couple of extra lines of code (basically just 1 extra for loop around the part that does lead-field calculation), it can be edited to go through a matrix of dipole coordinates and orientations. I'm currently on vacation, so it might take some time for me to dig up modifications I did for it to go through multiple dipoles, but it it took me maybe 10 minutes to fix in total, so it's really easy.<br><br></div><div>I think that the coordinates that you need to give for each dipole are voxel positions from the MRI. <br><br></div><div></div>There's also a bug near the end of the function, at the place where ft_senstype is called. It will set to MEG in both cases, so that needs fixing as well.<br><br><br></div>Later on, when you get the EEG, you can plot it like this, for example:<br><br>%View the EEG<br>cfg=[];<br>cfg.viewmode='vertical';<br>ft_databrowser(cfg,data_from_ft_dipolesimulation);<br><br><br></div>All the best, <br><span><span>Andreja Kostić</span></span><br><div><div><div><br><br></div></div></div></div><div class="gmail_extra"><br><div class="gmail_quote">2016-08-01 10:17 GMT+02:00 pooneh baniasad <span dir="ltr"><<a href="mailto:pooneh.baniasad@gmail.com" target="_blank">pooneh.baniasad@gmail.com</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_default" style="font-size:large"><div class="gmail_default"><span style="font-size:12.8px">Dear FieldTrip community,</span><br clear="all"></div><div style="font-size:small"><div class="gmail_default"></div><div class="gmail_default">I'm trying to generate EEG signal without using raw datas.</div><div class="gmail_default">I used the 'Subject01.mri' as my anatomical model, the BEM method for preparing a headmodel and 'standard_1020.elc' for aligning electrodes. </div><div class="gmail_default">For a source model I loaded template grid (cortex_20484.surf.gii).</div><div class="gmail_default">Now my questions are how can I set dipole's location (in other words, my grid's resolution)?</div><div class="gmail_default">How can I allocate a source model (sin, cos, ...) to each dipole? Is there any function in Fieldtrip doing that? or I have to writing the code by myself. </div><div class="gmail_default">After having the source model for each dipole and calculating leadfield matrix what should I do for plotting the EEG signal? </div><span class="HOEnZb"><font color="#888888"><div><br></div></font></span></div></div><span class="HOEnZb"><font color="#888888"><div><br></div>-- <br><div><div dir="ltr">Bests<div><br></div><div>Pouneh Baniasad</div></div></div>
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