<html><head></head><body><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:small;"><p class="ydpfb2c5bc4MsoNormal" style="line-height: normal;"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Hi Jason,</span></p>
<p class="ydpfb2c5bc4MsoNormal" style="line-height: normal;"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A"> Thank you and lets agree to a few basics
that I am sure you will agree to and may
help in our discourse: </span></p>
<div style="line-height: normal;"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Lets
agree that once the fundamental Physics of an electrical potential has been
replaced by a different and altered reality then this invalidates all
subsequent analyses because the original measures of mother of the brain is the
physics of the universe and not a mathematical concept like ICA used to replace the original
natural physics of the brain.</span></div><div style="line-height: normal;"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A"><br></span></div><div style="line-height: normal;"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">My replies are below your questions:</span></div>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A"> </span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">“Robert,</span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Thanks for the
clarification. So do I understand correctly that for the comparisons you are
showing, you (1) manually selected non-blink segments and ran the “pre”
measures, then (2) used EEGLAB to run ICA on the complete datasets, then (3)
selected the (single) eye-blink component from the independent components (ICs)
and removed it, then (4) again extracted the same previously manually selected
non-blink segments from the (back-projected, ICA blink-free) EEG.data, and ran
the measures again to produce the “delorme” results?”</span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Reply: Yes on #1 but no on #2 because it was
clinicians in Australia that used WinEEG ICA reconstruction after removing one
ICA component that represented the eye movement artifact. The clinicians had noticed large differences in
coherence and phase differences between the original artifact free selections
as compared to the ICA reconstructed data during a workshop. As explained by Ramesh Srinivasan eye
movement artifact is broad band and superimposed on all EEG channels and not
just the frontal leads. Delorme
performed his own EEGLAB ICA reconstruction and he did not use the WinEEG
ICA. Both the Australian clinicians and
Arno used 18 ICA components to reconstruct 19 channels – both created something
out of nothing or like Georges states: “I will give you 18 bitcoins if you give
me 19”.</span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A"> </span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">“Focusing on the
coherence results, it is surprising to me that removing only a frontally
concentrated eye-blink component would significantly change the coherence in
non-blink segments between say P4 and T6 electrodes, in non-blink, or even
blink segments. I believe the impact of these findings would be greatly
enhanced if you or your colleagues at Applied Neuroscience could produce (1)
the ICA component maps that were rejected in this analysis, (2) the actual
coherence values (not just the p-values), and (3) the datasets you used,
including the original data and the manually selected blink-free data, so that
the results could be reproduced and verified by others. Apologies again if you
have been over this previously in the discussion.”</span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A"> </span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Reply: As explained by Ramesh Srinivasan eye
movement artifact is broad band and superimposed on all EEG channels and not
just the frontal leads. I have posted .zip
files that contain all the numbers that you are mentioning. This is how Arno was able to perform his own
independent ICA reconstruction which also altered all of the phase differences
like the Australian clinicians did. Here
is a url to the .zip files so that you can download and do your own analyses
and comparisons. </span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A"> </span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">“One of the central
motivations of the ICA approach is that channel level coherence is
fundamentally misleading since brain sources in a particular area may project
widely across most or all electrodes, so that coherence between electrodes at
different channel locations is not a valid measure of coherence between brain
regions corresponding to those locations. Non-zero phase lag is not as
susceptible to this criticism as single sources will project with zero
phase-lag, though still the attribution of the “source” of the activity to the
brain region below the channel is suspect. However, that said, ICA advocates
would not expect the channel coherence that exists between non-frontal channels
to be significantly altered by the removal of an eye-blink IC, and, particularly
given the consternation created in the clinical field, it would be of great
importance to determine the cause.”</span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Reply: I disagree that
“coherence is fundamentally misleading”.
Volume conduction occurs at zero phase lag and one can use the imaginary
component of the cross-spectrum to eliminate the volume conduction component. Also, one can use directed coherence or the
phase slope index or lagged coherence, etc.
Unfortunately, ICA adulteration of the original time points invalidates
these non-volume conduction measures as much if not more than coherence. </span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Best wishes,</span></p>
<p class="ydpfb2c5bc4MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:"Times New Roman";color:#26282A">Robert</span></p>
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