<div dir="ltr"><div><div>Dear past recipients of this code (and eeglablist),</div><div><br></div><div>Sorry I told you a wrong way of calculating absolute power using spectopo(). Please accept my sincere apologies. If you are using the old code I sent you before, please replace it with the correct one.</div><div><br></div><div>Thank you Jerry Zhu for pointing it out!</div><div><br></div><div>Makoto</div><div><br></div><div><br></div><div>Correct<br></div><div>%%%%%%%%%%%%%%%%%%%</div><div><div><div>% for your epoched data, channel 2</div><div>[spectra,freqs] = spectopo(EEG.data(2,:,:), 0, EEG.srate);</div><div><br></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></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></div><div><br></div><div>Incorrect:<br></div><div><div>%%%%%%%%%%%%%%%%%%%</div><div><div><div>% compute absolute power<br></div><div>deltaPower = 10^(mean(spectra(deltaIdx))/10);</div><div>thetaPower = 10^(mean(spectra(thetaIdx))/10);</div><div>alphaPower = 10^(mean(spectra(alphaIdx))/10);</div><div>betaPower  = 10^(mean(spectra(betaIdx))/10);</div><div>gammaPower = 10^(mean(spectra(gammaIdx))/10);</div></div><div>%%%%%%%%%%%%%%%%%</div></div></div><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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