<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 11 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]--><o:SmartTagType
namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PersonName"/>
<!--[if !mso]>
<style>
st1\:*{behavior:url(#default#ieooui) }
</style>
<![endif]-->
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:blue;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-reply;
font-family:Arial;
color:navy;}
@page Section1
{size:595.3pt 841.9pt;
margin:1.0in 1.25in 1.0in 1.25in;}
div.Section1
{page:Section1;}
-->
</style>
</head>
<body lang=EN-US link=blue vlink=blue>
<div class=Section1>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Dear Brian,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Allow me to point you to a quite related
problem which has been posted by Nathan about a month ago. I think it was the
beginning of March. You can browse through the discussion list’s history
when you go to the fieldtrip-website and click around a bit at the appropriate
links. Even though the question here was related to LCMV-beamformer, the
problems might have the same cause.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Following Nathan’s thread, a very
likely cause is the incorrect specification of cfg.mriunits, and
cfg.sourceunits prior to calling sourceinterpolate (I did not find back in the
code you sent in your mail that you actually called it, but I assume you did). If
not specified, fieldtrip puts cfg.mriunits to ‘mm’, and
cfg.sourceunits to ‘cm’. There might be a discrepancy in your data
there. Perhaps you even explicitly have to check, whether your headmodel (in
hdmfile) is defined in cm. At least the dipole-grid on which sourceanalysis
performs the beamformer-scanning is defined in cm, and I guess the units should
be identical here as well.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Good luck,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Jan-Mathijs<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<div>
<div class=MsoNormal align=center style='text-align:center'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center tabindex=-1>
</span></font></div>
<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> <st1:PersonName
w:st="on">FieldTrip discussion list</st1:PersonName> [mailto:FIELDTRIP@NIC.SURFNET.NL]
<b><span style='font-weight:bold'>On Behalf Of </span></b>Brian Roach<br>
<b><span style='font-weight:bold'>Sent:</span></b> Thursday, March 29, 2007
1:08 AM<br>
<b><span style='font-weight:bold'>To:</span></b> FIELDTRIP@NIC.SURFNET.NL<br>
<b><span style='font-weight:bold'>Subject:</span></b> [FIELDTRIP] source
analysis attempt using DICS method</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Attached is the output from a call to sourceinterp on source analysis
output data. I am trying to use the DICS method, but my output looks
nothing like the tutorial pictures. I am including what I believe to be
the relevant code, and advice on the source of my mistake(s) would be
appreciated:<br>
<br>
[EEG com] = pop_loadbv('/home/bjr39/FTsource', 'B22001hal.vhdr')<br>
EEG1 = pop_select(EEG)<br>
help eeglab2fieldtrip<br>
data = eeglab2fieldtrip(EEG1, 'preprocessing')<br>
<br>
<font color=red><span style='color:red'>%%%<br>
there is some code which I have not included that string matches my electrodes
and uses coordinate that put the sites in MNI space according to the
coordinates listed here:<a
href="http://oase.uci.ru.nl/~roberto/electrode/realistic_1005.txt"
eudora=autourl>http://oase.uci.ru.nl/~roberto/electrode/realistic_1005.txt<br>
</a>%%%<br>
<br>
</span></font>cfg.output = 'powandcsd';<br>
cfg.method = 'mtmfft';<br>
cfg.foilim = [5 100];<br>
cfg.tapsmofrq = 2;<br>
cfg.foilim = [35 45];<br>
freq = freqanalysis(cfg, data)<br>
<br>
cfg = [];<br>
cfg.method = 'dics';<br>
cfg.frequency = 40;<br>
cfg.hdmfile = '/home/bjr39/FTsource/vol.mat';<br>
cfg.resolution = 2<br>
pack;source = sourceanalysis(cfg, freq)<br>
<br>
sourcePost = sourcedescriptives([], source)<br>
<br>
cfg =[];<br>
cfg.downsample = 2;<br>
cfg.funparameter = 'nai';<br>
cfg.colmin = 'auto';<br>
cfg.colmax = 'auto';<br>
sourcePostF = source2full(sourcePost);<br>
sliceinterp(cfg,sourceInterp);<br>
<br>
<br>
I can share more info if it will help, related to the size of different data
structures, or whatever anyone would need to know. I followed the guide
for head model creation and plotted it at various points (one plot previously
posted to the list). Could a poor head model create this problem?<br>
<br>
thanks,<br>
Brian<o:p></o:p></span></font></p>
</div>
</body>
</html>