<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px"><div id="yiv1058388329"><div id="yui_3_16_0_1_1431171950434_76584"><div id="yui_3_16_0_1_1431171950434_76583" style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"><div class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68356" style=""><font id="yui_3_16_0_1_1431171950434_76748" size="2"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68879" style="">Dear All,</span></font></div><div class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68787" style=""><font size="2"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_71168" style=""><br class="yiv1058388329" style="" clear="none"></span></font></div><div class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68472" style=""><font id="yiv1058388329yui_3_16_0_1_1431171950434_71354" size="2"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68579" style="">Thanks for the useful discussion.</span></font></div><div class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68428" style=""><font size="2"><br class="yiv1058388329" style="" clear="none"><span class="yiv1058388329" style=""></span></font></div><div class="yiv1058388329" dir="ltr" id="yiv1058388329yui_3_16_0_1_1431171950434_68422" style=""><div id="yui_3_16_0_1_1431171950434_76835" dir="ltr"><font id="yiv1058388329yui_3_16_0_1_1431171950434_71312" size="2"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68427" style="">In the same regard, I have tried to run spectopo on single dataset but, I'm blurred with the result. Why the power is negative? what does it mean?</span></font></div></div><div class="yiv1058388329" dir="ltr" id="yiv1058388329yui_3_16_0_1_1431171950434_71314" style=""><br clear="none"><font id="yiv1058388329yui_3_16_0_1_1431171950434_71312" size="2"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68427" style=""></span></font></div><div class="yiv1058388329" dir="ltr" id="yiv1058388329yui_3_16_0_1_1431171950434_71315" style=""><font class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_71312" style="" size="2"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68427" style="">The </span></font><font class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_71312" style="" size="2"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68427" style="">spectopo is <a rel="nofollow" shape="rect" id="yiv1058388329yui_3_16_0_1_1431171950434_71360" target="_blank" href="https://www.dropbox.com/s/q4v0nappwhvk1p5/spectopo%20topography.png?dl=0">spectopo topography.png</a><br clear="none"></span></font></div><div class="yiv1058388329link-enhancr-attachment yiv1058388329link-enhancr-element" id="yiv1058388329enhancrCard_0" style="width:450px;font-family:'Georgia', 'Times', 'Times New Roman', 'serif';margin-top:5px;margin-bottom:5px;background-color:#ffffff;"><table class="yiv1058388329link-enhancr-element" id="yiv1058388329yui_3_16_0_1_1431171950434_71380" style="width:450px;height:170px;display:block;" border="0" cellpadding="0" cellspacing="0"><tbody id="yiv1058388329yui_3_16_0_1_1431171950434_71379"><tr class="yiv1058388329link-enhancr-element" id="yiv1058388329yui_3_16_0_1_1431171950434_71389"><td colspan="8" rowspan="1" class="yiv1058388329link-enhancr-element" id="yiv1058388329yui_3_16_0_1_1431171950434_71388" style="height:1px;background-color:#e5e5e5;font-size:1px;border-collapse:collapse;"><div class="yiv1058388329link-enhancr-element" 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style="height:1px;background-color:#e5e5e5;font-size:1px;border-collapse:collapse;"><div class="yiv1058388329link-enhancr-element" style="height:1px;background-color:#e5e5e5;font-size:1px;line-height:0px;"> </div></td></tr></tbody></table></div><div class="yiv1058388329" dir="ltr" id="yiv1058388329yui_3_16_0_1_1431171950434_68545" style=""><font size="2"><br class="yiv1058388329" style="" clear="none"><span class="yiv1058388329" id="yiv1058388329yui_3_16_0_1_1431171950434_68427" style=""></span></font></div><font id="yui_3_16_0_1_1431171950434_77125" size="2"> <br class="yiv1058388329" style="" clear="none"></font><div id="yui_3_16_0_1_1431171950434_77128" dir="ltr">AHMED</div><div id="yiv1058388329yui_3_16_0_1_1431171950434_71030"> </div><div class="yiv1058388329signature" id="yiv1058388329yui_3_16_0_1_1431171950434_71031"> <br clear="none"></div><br clear="none"> <div id="yiv1058388329yui_3_16_0_1_1431171950434_71172" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div id="yiv1058388329yui_3_16_0_1_1431171950434_71171" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div class="qtdSeparateBR"><br><br></div><div class="yiv1058388329yqt7648186536" id="yiv1058388329yqt28792"><div dir="ltr" id="yiv1058388329yui_3_16_0_1_1431171950434_71170"> <hr id="yui_3_16_0_1_1431171950434_77147" size="1"> <font id="yiv1058388329yui_3_16_0_1_1431171950434_71173" face="Arial" size="2"> <b><span style="font-weight:bold;">From:</span></b> Makoto Miyakoshi <mmiyakoshi@ucsd.edu><br clear="none"> <b><span style="font-weight:bold;">To:</span></b> #SHAN XIN# <SHAN0055@e.ntu.edu.sg> <br clear="none"><b><span style="font-weight:bold;">Cc:</span></b> "eeglablist@sccn.ucsd.edu" <eeglablist@sccn.ucsd.edu> <br clear="none"> <b><span style="font-weight:bold;">Sent:</span></b> Friday, May 8, 2015 2:40 AM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> Re: [Eeglablist] How can I get the power of each frequency band?<br clear="none"> </font> </div> <div class="yiv1058388329y_msg_container"><br clear="none"><div id="yiv1058388329"><div><div dir="ltr">Dear Shan,<div><br clear="none"></div><div>Correct me if I'm wrong--I guess you are concerned with the number of sampling points in frequency. For example, if there are 4, 5, 6, 7 Hz in theta, and 8, 9, 10, 11, 12, 13 Hz in alpha, the former has 4 points while the latter has 6 points, therefore they should be normalized by the number of the frequency sampling points (i.e. to use the mean value within each frequency range 'bin'). If that's the case, yes I agree with you.</div><div><br clear="none"></div><div>Makoto</div><div class="yiv1058388329gmail_extra"><br clear="none"><div class="yiv1058388329qtdSeparateBR"><br clear="none"><br clear="none"></div><div class="yiv1058388329yqt3474663509" id="yiv1058388329yqt22514"><div class="yiv1058388329gmail_quote">On Tue, May 5, 2015 at 11:23 PM, #SHAN XIN# <span dir="ltr"><<a rel="nofollow" shape="rect" ymailto="mailto:SHAN0055@e.ntu.edu.sg" target="_blank" href="mailto:SHAN0055@e.ntu.edu.sg">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none"><blockquote class="yiv1058388329gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex;">
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<div>Dear Makoto,<br clear="none">
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<div>Thank you for your explanation!!<br clear="none">
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<div>For the "length of each discrete frequency", I mean the length of each frequency bin.
<span style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);">
Let's say the density is "5uV^2/Hz" for one particular alphaIdx (one frequency bin), and assume the length of this frequency bin is 0.5 Hz. If we can directly sum all values, then actually you mean 5uV^2 is already the power in this frequency bin. Or the
power is actually 2.5uV^2, such that the density is 2.5uV^2/0.5Hz=5uV^2/Hz ? I</span>f it is the second case, then before summation we should first multiply the density by the length, right? I don't know which one is correct...<br clear="none">
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<div><span style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);"><br clear="none">
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<div><span style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);">Best wishes,</span></div>
<div><span style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);">SHAN Xin</span></div>
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<div dir="ltr"><font style="font-size:11pt;" color="#000000" face="Calibri, sans-serif"><b>From:</b> Makoto Miyakoshi <<a rel="nofollow" shape="rect" ymailto="mailto:mmiyakoshi@ucsd.edu" target="_blank" href="mailto:mmiyakoshi@ucsd.edu">mmiyakoshi@ucsd.edu</a>><br clear="none">
<b>Sent:</b> Tuesday, 5 May 2015 11:04 PM</font><div><div class="yiv1058388329h5"><br clear="none">
<b>To:</b> #SHAN XIN#<br clear="none">
<b>Cc:</b> <a rel="nofollow" shape="rect" ymailto="mailto:eeglablist@sccn.ucsd.edu" target="_blank" href="mailto:eeglablist@sccn.ucsd.edu">eeglablist@sccn.ucsd.edu</a><br clear="none">
<b>Subject:</b> Re: [Eeglablist] How can I get the power of each frequency band?</div></div>
<div> </div>
</div><div><div class="yiv1058388329h5">
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<div dir="ltr">Dear Shan,
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<div><span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;">> (1) Since dB is the log ratio of two same quantities, so in the spectopo plot </span><span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;">10log</span><sub style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;">10</sub><span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;">(</span><span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;color:rgb(33,33,33);">uV^2/Hz) </span><span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;">, does
EEGlab implicitly assume that the reference level is 1uV</span><span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;color:rgb(33,33,33);">^2</span><span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;"> ?</span><br clear="none">
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<div>I once tested it myself.</div>
<div>I generated a long sine wave with amplitude of 1 and 10 Hz and ran spectopo. The peak at 10 Hz was at 0. When I change the amplitude to 10, the peak level was at 20 (if I remember correctly).</div>
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<div><span style="font-size:12pt;">> (2) The script line "</span><span style="color:rgb(255,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12.6666669845581px;">deltaPower = mean(10.^(spectra(deltaIdx)/10)); </span><span style="font-size:12pt;">"
gives </span><span style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;">uV^2/Hz, which is the mean value of densities</span><span style="font-size:12pt;">. If I hope to get the total power within alpha band, what script
should I write? </span>Intuitively it seems something like: total power=sum(10.^(spectra(<span style="font-size:12pt;">alphaIdx)/10)</span><span style="font-size:12pt;">*(</span><span style="font-size:12pt;">length of each discrete frequency</span><span style="font-size:12pt;">)</span><span style="font-size:12pt;">).</span><span style="font-size:12pt;"> </span><span style="font-size:12pt;"> </span><span style="font-size:12pt;">I</span><span style="font-size:12pt;">s
this concept</span><span style="font-size:12pt;"> correc</span><span style="font-size:12pt;">t? If it is correct, then what should be the value for "</span><span style="font-size:12pt;">length of each discrete frequency" (say for 128Hz sampling rate)? If not,
then is there actually any method to get the total power?</span><br clear="none">
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<div><span style="font-size:12pt;">I have never wished to have the total power so I'm not completely sure, but</span></div>
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<div>> total power=sum(10.^(spectra(<span style="font-size:12pt;">alphaIdx)/10)</span><span style="font-size:12pt;">*(</span><span style="font-size:12pt;">length of each discrete frequency</span><span style="font-size:12pt;">)</span><span style="font-size:12pt;">)</span><span style="font-size:12pt;"><br clear="none">
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<div><span style="font-size:16px;">What is the 'length of each discrete frequency' here? What 'length' is it referring to? Isn't it simply </span>sum(10.^(spectra(<span style="font-size:12pt;">alphaIdx)/10)?</span></div>
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<div><span style="font-size:16px;">Makoto</span></div>
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<div class="yiv1058388329gmail_extra"><br clear="none">
<div class="yiv1058388329gmail_quote">On Thu, Apr 23, 2015 at 9:17 AM, #SHAN XIN# <span dir="ltr">
<<a rel="nofollow" shape="rect" ymailto="mailto:SHAN0055@e.ntu.edu.sg" target="_blank" href="mailto:SHAN0055@e.ntu.edu.sg">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none">
<blockquote class="yiv1058388329gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex;">
<div dir="ltr">
<div style="background-color:rgb(255,255,255);">
<div style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12pt;">
Dear Makoto,<br clear="none">
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<div style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12pt;">
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<div style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12pt;">
Thank you so much for the link!! I still have two questions:<br clear="none">
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<div style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12pt;">
(1) Since dB is the log ratio of two same quantities, so in the spectopo plot <span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);">10log</span><sub style="font-family:Calibri, Arial, Helvetica, sans-serif;background-color:rgb(255,255,255);">10</sub><span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);">(</span><span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;color:rgb(33,33,33);background-color:rgb(255,255,255);">uV^2/Hz) </span>, does
EEGlab implicitly assume that the reference level is 1uV<span style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);">^2</span> ?<br clear="none">
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<div><span style="font-size:12pt;">(2) The script line "</span><span style="color:rgb(255,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12.6666669845581px;">deltaPower = mean(10.^(spectra(deltaIdx)/10)); </span><span style="font-size:12pt;">" gives </span><span style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);">uV^2/Hz,
which is the mean value of densities</span><span style="font-size:12pt;">. If I hope to get the total power within alpha band, what script should I write? </span>Intuitively it seems something like: total power=sum(10.^(spectra(<span style="font-size:12pt;">alphaIdx)/10)</span><span style="font-size:12pt;">*(</span><span style="font-size:12pt;">length
of each discrete frequency</span><span style="font-size:12pt;">)</span><span style="font-size:12pt;">).</span><span style="font-size:12pt;"> </span><span style="font-size:12pt;"> </span><span style="font-size:12pt;">I</span><span style="font-size:12pt;">s this concept</span><span style="font-size:12pt;"> correc</span><span style="font-size:12pt;">t?
If it is correct, then what should be the value for "</span><span style="font-size:12pt;">length of each discrete frequency" (say for 128Hz sampling rate)? If not, then is there actually any method to get the total power?</span></div>
<div><span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;background-color:rgb(255,255,255);"><br clear="none">
</span></div>
<div>Best wishes,<br clear="none">
</div>
<div style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12pt;">
SHAN Xin<br clear="none">
</div>
<div style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12pt;">
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<div style="color:rgb(33,33,33);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12pt;">
<hr style="display:inline-block;width:98%;">
<div dir="ltr"><font style="font-size:11pt;" color="#000000" face="Calibri, sans-serif"><b>From:</b> Makoto Miyakoshi <<a rel="nofollow" shape="rect" ymailto="mailto:mmiyakoshi@ucsd.edu" target="_blank" href="mailto:mmiyakoshi@ucsd.edu">mmiyakoshi@ucsd.edu</a>><br clear="none">
<b>Sent:</b> Wednesday, 22 April 2015 2:07 AM
</font><div>
<div><br clear="none">
<b>To:</b> #SHAN XIN#<br clear="none">
<b>Cc:</b> <a rel="nofollow" shape="rect" ymailto="mailto:eeglablist@sccn.ucsd.edu" target="_blank" href="mailto:eeglablist@sccn.ucsd.edu">eeglablist@sccn.ucsd.edu</a><br clear="none">
<b>Subject:</b> Re: [Eeglablist] How can I get the power of each frequency band?</div>
</div>
<div> </div>
</div>
<div>
<div>
<div>
<div dir="ltr">Dear Shan,
<div><br clear="none">
</div>
<div>> Why divided by Hz?<br clear="none">
</div>
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</div>
<div>Here is (esoteric) discussion about the related topic. </div>
<div><a rel="nofollow" shape="rect" target="_blank" href="http://sccn.ucsd.edu/pipermail/eeglablist/2014/008224.html">http://sccn.ucsd.edu/pipermail/eeglablist/2014/008224.html</a><br clear="none">
</div>
<div><br clear="none">
</div>
<div>Makoto</div>
<div class="yiv1058388329gmail_extra"><br clear="none">
<div class="yiv1058388329gmail_quote">On Mon, Apr 20, 2015 at 3:58 AM, #SHAN XIN# <span dir="ltr">
<<a rel="nofollow" shape="rect" ymailto="mailto:SHAN0055@e.ntu.edu.sg" target="_blank" href="mailto:SHAN0055@e.ntu.edu.sg">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none">
<blockquote class="yiv1058388329gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex;">
<div>
<div>Hi Makoto,</div>
<div><br clear="none">
</div>
<div>Oh I didn't realize the scale on the figure might already in dB...is it? I know dB is defined as log ratio, but uV^2/Hz does not seem to be a ratio since the units (volt square and hz) do not match... Also, do you therefore mean that the definition of
absolute power is <span>uV^2/Hz?</span></div>
<div><br clear="none">
</div>
<div>I've gone through the related topics in archives and still don't understand these... I also search on Google but still cannot find a clear explanation. Why divided by Hz?</div>
<span>
</span><div><br clear="none">
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<div>Thank you so much!!</div>
<div><br clear="none">
</div>
<div>Shan Xin</div>
<div>
<div>
<div><br clear="none">
#SHAN XIN# <<a rel="nofollow" shape="rect" ymailto="mailto:SHAN0055@e.ntu.edu.sg" target="_blank" href="mailto:SHAN0055@e.ntu.edu.sg">SHAN0055@e.ntu.edu.sg</a>> 於 Apr 20, 2015 17:29 寫道：<br clear="none">
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<blockquote type="cite">
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<div style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;background-color:rgb(255,255,255);">
<div>Dear Makoto,<br clear="none">
</div>
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<div>I have a doubt for the power unit. I read the "help spectopo" in Matlab, for the variable "spectra":<br clear="none">
</div>
<div><br clear="none">
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<div>Outputs:</div>
<div> spectra = (nchans,nfreqs) power spectra (mean power over epochs), in dB</div>
<div> freqs = frequencies of spectra (Hz)<br clear="none">
</div>
<div><br clear="none">
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<div>If the unit of variable "spectra" is in dB unit already, then when computing the absolute power, do we still need to do the transformation as you suggested (i.e.
<span style="color:rgb(255,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:12.6666669845581px;background-color:rgb(255,255,255);">
10.^(spectra(deltaIdx)/10)</span>)? <br clear="none">
</div>
<div><br clear="none">
</div>
<div>I know when plotting the figure, the spectrum is plotted in log scale. But if the unit of spectra is in dB, then there's no need to transform, right? <br clear="none">
</div>
<div><br clear="none">
</div>
<div>I don't know if this is correct... Could you look more into it? Thank you so much!!<br clear="none">
</div>
<div><br clear="none">
</div>
<div>Shan Xin<br clear="none">
</div>
<div><br clear="none">
</div>
<div style="color:rgb(33,33,33);">
<hr style="display:inline-block;width:98%;">
<div dir="ltr"><font style="font-size:11pt;" color="#000000" face="Calibri, sans-serif"><b>From:</b> Makoto Miyakoshi <<a rel="nofollow" shape="rect" ymailto="mailto:mmiyakoshi@ucsd.edu" target="_blank" href="mailto:mmiyakoshi@ucsd.edu">mmiyakoshi@ucsd.edu</a>><br clear="none">
<b>Sent:</b> Thursday, 16 April 2015 11:11 AM<br clear="none">
<b>To:</b> #SHAN XIN#<br clear="none">
<b>Cc:</b> <a rel="nofollow" shape="rect" ymailto="mailto:eeglablist@sccn.ucsd.edu" target="_blank" href="mailto:eeglablist@sccn.ucsd.edu">eeglablist@sccn.ucsd.edu</a><br clear="none">
<b>Subject:</b> Re: [Eeglablist] How can I get the power of each frequency band?</font>
<div> </div>
</div>
<div>
<div dir="ltr">
<div><span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;">Dear Shan,</span></div>
<span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;">
</span><div><span style="color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;"><br clear="none">
</span></div>
> I'm not very proficient in Matlab programming...<br clear="none">
<div class="yiv1058388329gmail_extra"><br clear="none">
</div>
<div class="yiv1058388329gmail_extra">This could be a concern but you can try!</div>
<div class="yiv1058388329gmail_extra"><br clear="none">
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<div class="yiv1058388329gmail_extra">
<div style="font-size:12.6666669845581px;">%%%%%%%%%%%%%%%%%%%</div>
<div style="font-size:12.6666669845581px;">
<div>
<div>% for your epoched data, channel 2</div>
<div>[spectra,freqs] = spectopo(EEG.data(2,:,:), 0, EEG.srate);</div>
<div><br clear="none">
</div>
<div>% delta=1-4, theta=4-8, alpha=8-13, beta=13-30, gamma=30-80</div>
<div>deltaIdx = find(freqs>1 & freqs<4);</div>
<div>thetaIdx = find(freqs>4 & freqs<8);</div>
<div>alphaIdx = find(freqs>8 & freqs<13);</div>
<div>betaIdx = find(freqs>13 & freqs<30);</div>
<div>gammaIdx = find(freqs>30 & freqs<80);</div>
<div><br clear="none">
</div>
<div><font color="#ff0000">% compute absolute power</font></div>
<div><font color="#ff0000">deltaPower = mean(10.^(spectra(deltaIdx)/10));</font></div>
<div><font color="#ff0000">thetaPower = mean(10.^(spectra(thetaIdx)/10));</font></div>
<div><font color="#ff0000">alphaPower = mean(10.^(spectra(alphaIdx)/10));</font></div>
<div><font color="#ff0000">betaPower = mean(10.^(spectra(betaIdx)/10));</font></div>
<div><font color="#ff0000">gammaPower = mean(10.^(spectra(gammaIdx)/10));</font></div>
</div>
<div>%%%%%%%%%%%%%%%%%</div>
<div><br clear="none">
</div>
<div>Makoto</div>
</div>
</div>
<div class="yiv1058388329gmail_extra"><br clear="none">
</div>
<div class="yiv1058388329gmail_extra"><br clear="none">
<div class="yiv1058388329gmail_quote">On Tue, Apr 14, 2015 at 6:23 AM, #SHAN XIN# <span dir="ltr">
<<a rel="nofollow" shape="rect" ymailto="mailto:SHAN0055@e.ntu.edu.sg" target="_blank" href="mailto:SHAN0055@e.ntu.edu.sg">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none">
<blockquote class="yiv1058388329gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex;">
<div dir="ltr">
<div style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;background-color:rgb(255,255,255);">
<div><span style="font-size:12pt;">Hi EEGLab team,</span></div>
<div dir="ltr" style="color:rgb(33,33,33);">
<div>
<div style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri, Arial, Helvetica, sans-serif;background-color:rgb(255,255,255);">
<div><br clear="none">
Does EEGlab has plugin or script so that I can get the power of individual band (e.g. power of alpha band or beta band) from your computation, instead of just a continuous line in the power spectrum figure? I'm not very proficient in Matlab programming...t<span style="font-size:12pt;">hank
you so much!!</span></div>
<div><br clear="none">
</div>
<div>Best wishes,<br clear="none">
</div>
<div>SHAN Xin<br clear="none">
</div>
<div><br clear="none">
</div>
<div><br clear="none">
</div>
</div>
</div>
</div>
</div>
</div>
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-- <br clear="none">
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<div dir="ltr">Makoto Miyakoshi<br clear="none">
Swartz Center for Computational Neuroscience<br clear="none">
Institute for Neural Computation, University of California San Diego<br clear="none">
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<div dir="ltr">Makoto Miyakoshi<br clear="none">
Swartz Center for Computational Neuroscience<br clear="none">
Institute for Neural Computation, University of California San Diego<br clear="none">
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Swartz Center for Computational Neuroscience<br clear="none">
Institute for Neural Computation, University of California San Diego<br clear="none">
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</blockquote></div></div><br clear="none"><br clear="all"><div><br clear="none"></div>-- <br clear="none"><div class="yiv1058388329gmail_signature"><div dir="ltr">Makoto Miyakoshi<br clear="none">Swartz Center for Computational Neuroscience<br clear="none">Institute for Neural Computation, University of California San Diego<br clear="none"></div></div>
</div></div></div></div><br clear="none"><div class="yiv1058388329yqt3474663509" id="yiv1058388329yqt36664">_______________________________________________<br clear="none">Eeglablist page: <a rel="nofollow" shape="rect" target="_blank" href="http://sccn.ucsd.edu/eeglab/eeglabmail.html">http://sccn.ucsd.edu/eeglab/eeglabmail.html</a><br clear="none">To unsubscribe, send an empty email to <a rel="nofollow" shape="rect" ymailto="mailto:eeglablist-unsubscribe@sccn.ucsd.edu" target="_blank" href="mailto:eeglablist-unsubscribe@sccn.ucsd.edu">eeglablist-unsubscribe@sccn.ucsd.edu</a><br clear="none">For digest mode, send an email with the subject "set digest mime" to <a rel="nofollow" shape="rect" ymailto="mailto:eeglablist-request@sccn.ucsd.edu" target="_blank" href="mailto:eeglablist-request@sccn.ucsd.edu">eeglablist-request@sccn.ucsd.edu</a></div><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div></body></html>