<div dir="ltr">Dear Ahmed,<div><br></div><div>0 in the vertical scale means your sine wave has amplitude of 1. If it is 10, the scale should point to 20. -40 means 1/100, -60 means 1/1000, etc... somehow your signal seems very small. Usually eye blinks etc are around 20.</div><div><br></div><div>Makoto</div><div class="gmail_extra"><br><div class="gmail_quote">On Sat, May 9, 2015 at 9:29 AM, Ahmed Almurshedi <span dir="ltr"><<a href="mailto:ahmed19875000@yahoo.com" target="_blank">ahmed19875000@yahoo.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:13px"><div><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"><div><font size="2"><span>Dear All,</span></font></div><div><font size="2"><span><br clear="none"></span></font></div><div><font size="2"><span>Thanks for the useful discussion.</span></font></div><div><font size="2"><br clear="none"><span></span></font></div><div dir="ltr"><div dir="ltr"><font size="2"><span>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 dir="ltr"><br clear="none"><font size="2"><span></span></font></div><div dir="ltr"><font size="2"><span>The </span></font><font size="2"><span>spectopo is <a rel="nofollow" shape="rect" href="https://www.dropbox.com/s/q4v0nappwhvk1p5/spectopo%20topography.png?dl=0" target="_blank">spectopo topography.png</a><br clear="none"></span></font></div><div style="width:450px;font-family:'Georgia','Times','Times New Roman','serif';margin-top:5px;margin-bottom:5px;background-color:#ffffff"><table style="width:450px;height:170px;display:block" border="0" cellpadding="0" cellspacing="0"><tbody><tr><td colspan="8" rowspan="1" style="height:1px;background-color:#e5e5e5;font-size:1px;border-collapse:collapse"><div style="min-height:1px;background-color:#e5e5e5;font-size:1px;line-height:0px"> </div></td></tr><tr><td colspan="1" rowspan="5" style="width:1px;background-color:#e5e5e5;font-size:1pt;border-collapse:collapse"><div style="width:1px;background-color:#e5e5e5;font-size:1pt"> </div></td><td colspan="1" rowspan="5" style="vertical-align:middle;width:168px;height:168px;background-color:#000000;border-collapse:collapse"><div style="width:168px" align="center"><a rel="nofollow" shape="rect" href="https://www.dropbox.com/s/q4v0nappwhvk1p5/spectopo%20topography.png?dl=0" style="text-decoration:none;color:#000000" target="_blank"><img alt="image" src="https://photos-4.dropbox.com/t/2/AABVwp9BoT-yd6S2QcVcNN1BDKb6MCJveKA99zFFEnWxsg/12/158636242/png/1024x1024/2/_/0/4/spectopo%20topography.png/CNKx0ksgASACIAMgBCAFKAEoAg/q4v0nappwhvk1p5/AADJ0skpv2c4ipVRELajY7pja/spectopo%20topography.png" style="display:block;margin:auto" height="140" width="168"></a></div></td><td colspan="1" rowspan="5" style="width:1px;background-color:#e5e5e5;font-size:0pt;border-collapse:collapse"><div style="width:1px;background-color:#e5e5e5;font-size:1pt"> </div></td><td colspan="1" rowspan="5" style="width:14px;background-color:#ffffff;font-size:0pt;border-collapse:collapse"><div style="width:14px;background-color:#ffffff;font-size:14pt"> </div></td><td colspan="2" rowspan="1" style="height:6px;background-color:#ffffff;font-size:0pt;border-collapse:collapse"><div style="min-height:6px;background-color:#ffffff;font-size:6pt"> </div></td><td colspan="1" rowspan="5" style="width:20px;background-color:#ffffff;font-size:0pt;border-collapse:collapse"><div style="width:20px;background-color:#ffffff;font-size:20pt"> </div></td><td colspan="1" rowspan="5" style="width:1px;background-color:#e5e5e5;font-size:1pt;border-collapse:collapse" width="1"><div style="width:1px;background-color:#e5e5e5;font-size:1pt"> </div></td></tr><tr><td colspan="2" rowspan="1" style="width:100%;vertical-align:middle;font-family:'Georgia','Times','Times New Roman','serif'"><div style="line-height:16.5px;background-color:#ffffff;min-height:135px;width:245px"><div style="word-wrap:break-word"><span></span><span></span><a rel="nofollow" shape="rect" href="https://www.dropbox.com/s/q4v0nappwhvk1p5/spectopo%20topography.png?dl=0" style="text-decoration:none;color:#000000;line-height:100%;font-size:18px;display:block" target="_blank"><span style="margin:0;font-weight:normal;margin-bottom:3px;font-size:18px;line-height:21px;max-height:43px;color:#000000;overflow:hidden;display:inline-block">spectopo topography.png</span></a><div style="font-size:13px;line-height:20px;color:#999999;max-height:81px;font-family:'Georgia','Times','Times New Roman','serif';overflow:hidden">Shared with Dropbox</div></div></div></td></tr><tr><td colspan="2" rowspan="1" style="height:4px;background-color:#ffffff;font-size:0pt;border-collapse:collapse"><div style="min-height:4px;background-color:#ffffff;font-size:4pt"></div></td></tr><tr><td colspan="1" rowspan="1" style="vertical-align:middle;font-family:'Arial','Helvetica Neue','Helvetica','sans-serif'"><div style="font-size:0pt"><a rel="nofollow" shape="rect" href="https://www.dropbox.com/s/q4v0nappwhvk1p5/spectopo%20topography.png?dl=0" style="color:black;text-decoration:none" target="_blank"><span style="display:inline-block;line-height:11px;max-width:145px;min-width:85px;overflow:hidden;max-height:13px"><span style="vertical-align:middle;font-size:9px;line-height:11px;color:#999999">View on <span style="font-weight:bold">www.dropbox.com</span></span></span></a></div></td><td colspan="1" rowspan="1" style="vertical-align:middle;width:100px;font-family:'Arial','Helvetica Neue','Helvetica','sans-serif'"><div style="max-width:100px;min-width:80px;overflow:hidden;text-align:right;line-height:11px;max-height:13px;font-size:0pt"><span style="vertical-align:middle;font-size:9px;line-height:11px;color:#999999">Preview by Yahoo</span></div></td></tr><tr><td colspan="2" rowspan="1" style="height:9px;background-color:#ffffff;font-size:0pt;border-collapse:collapse"><div style="min-height:9px;background-color:#ffffff;font-size:9pt"></div></td></tr><tr><td colspan="8" rowspan="1" style="height:1px;background-color:#e5e5e5;font-size:1px;border-collapse:collapse"><div style="min-height:1px;background-color:#e5e5e5;font-size:1px;line-height:0px"> </div></td></tr></tbody></table></div><div dir="ltr"><font size="2"><br clear="none"><span></span></font></div><font size="2"> <br clear="none"></font><div dir="ltr">AHMED</div><div> </div><div> <br clear="none"></div><br clear="none"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div><br><br></div><div><div dir="ltr"> <hr size="1"> <font face="Arial" size="2"> <b><span style="font-weight:bold">From:</span></b> Makoto Miyakoshi <<a href="mailto:mmiyakoshi@ucsd.edu" target="_blank">mmiyakoshi@ucsd.edu</a>><br clear="none"> <b><span style="font-weight:bold">To:</span></b> #SHAN XIN# <<a href="mailto:SHAN0055@e.ntu.edu.sg" target="_blank">SHAN0055@e.ntu.edu.sg</a>> <br clear="none"><b><span style="font-weight:bold">Cc:</span></b> "<a href="mailto:eeglablist@sccn.ucsd.edu" target="_blank">eeglablist@sccn.ucsd.edu</a>" <<a href="mailto:eeglablist@sccn.ucsd.edu" target="_blank">eeglablist@sccn.ucsd.edu</a>> <br clear="none"> <b><span style="font-weight:bold">Sent:</span></b> Friday, May 8, 2015 2:40 AM<div><div class="h5"><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"> </div></div></font> </div><div><div class="h5"> <div><br clear="none"><div><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><br clear="none"><div><br clear="none"><br clear="none"></div><div><div>On Tue, May 5, 2015 at 11:23 PM, #SHAN XIN# <span dir="ltr"><<a rel="nofollow" shape="rect" href="mailto:SHAN0055@e.ntu.edu.sg" target="_blank">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none"><blockquote 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>Dear Makoto,<br clear="none">
</div>
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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">
</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)"><br clear="none">
</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)">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>
<div><br clear="none">
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<div style="color:rgb(0,0,0)">
<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" href="mailto:mmiyakoshi@ucsd.edu" target="_blank">mmiyakoshi@ucsd.edu</a>><br clear="none">
<b>Sent:</b> Tuesday, 5 May 2015 11:04 PM</font><div><div><br clear="none">
<b>To:</b> #SHAN XIN#<br clear="none">
<b>Cc:</b> <a rel="nofollow" shape="rect" href="mailto:eeglablist@sccn.ucsd.edu" target="_blank">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><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">
</div>
<div><br clear="none">
</div>
<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>
<div><br clear="none">
</div>
<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">
</div>
<div><span style="font-size:12pt"><br clear="none">
</span></div>
<div><span style="font-size:12pt">I have never wished to have the total power so I'm not completely sure, but</span></div>
<div><span style="font-size:12pt"><br clear="none">
</span></div>
<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">
</span></div>
<div><span style="font-size:12pt"><br clear="none">
</span></div>
<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>
<div><span style="font-size:16px"><br clear="none">
</span></div>
<div><span style="font-size:16px">Makoto</span></div>
<div><span style="font-size:12pt"><br clear="none">
</span></div>
<div><br clear="none">
<div>On Thu, Apr 23, 2015 at 9:17 AM, #SHAN XIN# <span dir="ltr">
<<a rel="nofollow" shape="rect" href="mailto:SHAN0055@e.ntu.edu.sg" target="_blank">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none">
<blockquote 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">
</div>
<div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">
<br clear="none">
</div>
<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">
<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">
</div>
<div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">
<br clear="none">
</div>
<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">
<br clear="none">
</div>
<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" href="mailto:mmiyakoshi@ucsd.edu" target="_blank">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" href="mailto:eeglablist@sccn.ucsd.edu" target="_blank">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>
<div><br clear="none">
</div>
<div>Here is (esoteric) discussion about the related topic. </div>
<div><a rel="nofollow" shape="rect" href="http://sccn.ucsd.edu/pipermail/eeglablist/2014/008224.html" target="_blank">http://sccn.ucsd.edu/pipermail/eeglablist/2014/008224.html</a><br clear="none">
</div>
<div><br clear="none">
</div>
<div>Makoto</div>
<div><br clear="none">
<div>On Mon, Apr 20, 2015 at 3:58 AM, #SHAN XIN# <span dir="ltr">
<<a rel="nofollow" shape="rect" href="mailto:SHAN0055@e.ntu.edu.sg" target="_blank">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none">
<blockquote 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">
</div>
<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" href="mailto:SHAN0055@e.ntu.edu.sg" target="_blank">SHAN0055@e.ntu.edu.sg</a>> 於 Apr 20, 2015 17:29 寫道：<br clear="none">
<br clear="none">
</div>
<blockquote type="cite">
<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>Dear Makoto,<br clear="none">
</div>
<div><br clear="none">
</div>
<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">
</div>
<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">
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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.
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10.^(spectra(deltaIdx)/10)</span>)? <br clear="none">
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<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">
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<div>I don't know if this is correct... Could you look more into it? Thank you so much!!<br clear="none">
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<div>Shan Xin<br clear="none">
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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" href="mailto:mmiyakoshi@ucsd.edu" target="_blank">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" href="mailto:eeglablist@sccn.ucsd.edu" target="_blank">eeglablist@sccn.ucsd.edu</a><br clear="none">
<b>Subject:</b> Re: [Eeglablist] How can I get the power of each frequency band?</font>
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<div><span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">Dear Shan,</span></div>
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> I'm not very proficient in Matlab programming...<br clear="none">
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<div>This could be a concern but you can try!</div>
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<div style="font-size:12.6666669845581px">%%%%%%%%%%%%%%%%%%%</div>
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<div>% for your epoched data, channel 2</div>
<div>[spectra,freqs] = spectopo(EEG.data(2,:,:), 0, EEG.srate);</div>
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<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>
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<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>
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<div>%%%%%%%%%%%%%%%%%</div>
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<div>Makoto</div>
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<div>On Tue, Apr 14, 2015 at 6:23 AM, #SHAN XIN# <span dir="ltr">
<<a rel="nofollow" shape="rect" href="mailto:SHAN0055@e.ntu.edu.sg" target="_blank">SHAN0055@e.ntu.edu.sg</a>></span> wrote:<br clear="none">
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<div><span style="font-size:12pt">Hi EEGLab team,</span></div>
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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>
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<div>Best wishes,<br clear="none">
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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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-- <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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-- <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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</blockquote></div></div><br clear="none"><br clear="all"><div><br clear="none"></div>-- <br clear="none"><div><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>_______________________________________________<br clear="none">Eeglablist page: <a rel="nofollow" shape="rect" href="http://sccn.ucsd.edu/eeglab/eeglabmail.html" target="_blank">http://sccn.ucsd.edu/eeglab/eeglabmail.html</a><br clear="none">To unsubscribe, send an empty email to <a rel="nofollow" shape="rect" href="mailto:eeglablist-unsubscribe@sccn.ucsd.edu" target="_blank">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" href="mailto:eeglablist-request@sccn.ucsd.edu" target="_blank">eeglablist-request@sccn.ucsd.edu</a></div><br clear="none"><br clear="none"></div></div></div></div> </div> </div> </div></div></div></div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr">Makoto Miyakoshi<br>Swartz Center for Computational Neuroscience<br>Institute for Neural Computation, University of California San Diego<br></div></div>
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