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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Dear EEGLAB community,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I am starting to use DIPFIT2 to localize brain sources of
PCA/ICA EEG components. I face a problem to decide how many dipoles to fit, i.e.
one unilateral vs two bilateral symmetrical. Some papers simply always assume 2
symmetrical sources. However, if component's topography is highly asymmetric,
this seems not to be justified. Furthermore, in case of a symmetric topography
one could often reasonably assume both one unilateral or two bilateral sources
both originating from brain structures close to the midline. Of course, solutions
may substantially differ for one and two sources. What is you experience and practice?
How do you solve this problem? Do you use any quantitative test? Residual
variance is always lower when two sources are fitted compared to one source. Is
there some rule to consider this reduction as significant, or can the reduction
of residual variance be statistically tested?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I will greatly appreciate any feedback and help. Thanks.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Igor<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:9.0pt'>-----------------------------<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>Igor Riecansky, MD PhD<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>SCAN-Unit<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>Institute of Clinical,
Biological and Differential Psychology<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>Faculty of Psychology<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>University of Vienna<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>Liebiggasse 5, A-1010 Austria<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>Tel.: +43-1-4277-47 509<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:9.0pt'>Room No. </span><span lang=DE
style='font-size:9.0pt'>O3.28<o:p></o:p></span></p>
<p class=MsoNormal><span lang=DE style='font-size:9.0pt'>E-mail:
igor.riecansky@univie.ac.at<o:p></o:p></span></p>
<p class=MsoNormal><span lang=DE><o:p> </o:p></span></p>
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