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MEG measures magnetic fields and EEG measures electrical potentials. One property of magnetic fields is that organic matter (scalp, skull, and brain) does not block them in any significant way. Electrical potentials measured on the scalp, on the other hand, are definitely affected by the matter between the source of the signal and the location they are ...


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You should consider using subject-specific alpha channels and frequency ranges. There are differences between individuals in alpha peak frequency. Also the placement of the EEG cap as well as small differences in orientations of cortex can affect which channels pick up perceptual activity. One way to do this would be to record data from the subject with ...


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Yes and sort of. Dry electrodes are known for lesser signal quality in comparison to "wet" electrodes. Adding some paste/gel to dry electrodes does help. My professor just got an Emotive Insight and found that this helped quite a bit. More electrodes does not automatically improve the channel to channel quality. However, more electrodes will allow you to ...


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The EEG signals between these regions will not be independent. The electrical activity that is being measured at the scalp, is the result of electrical flow inside the brain. This flow does not go in just one direction. It 'smears out' a little bit to surrounding areas, since the entire scalp/body is conductive. Another reason that the activity measured at ...


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You kind of have to do some kind of baseline correction first (or a highpass filter on the unepoched data) because of slow drifting. Lowpass filtering before artifact rejection is fine as long as you don't ever go back to the unfiltered signal in your analyses. After that, you can either throw out trials that exceed a set threshold, or you can do a two-step ...


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I don't exactly what it is you want, but if you are looking for other analyzing techniques, you should try Independent Component Analysis. I have heard (but I do not have references) that ICA is better than PCA analyses. A very neat (and free) Matlab toolbox that has this function is FieldTrip (http://www.fieldtriptoolbox.org/). It is a nicely documented ...



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