SleepWrangler wrote:OK. I assume we're looking at a Fourier transform of an EEG sensor in some sort of time compressed scale where the viewable bits represent a time period of whatever.
That's correct. This is a C3, the actual EEG is accurate (a "30 second epoch"), while the FFT graphic can be modified in re: frequency, viewing angle and amplitude.
SleepWrangler wrote:A previous standard enforced an archaic 75µV limitation, possibly to filter noise, but this particular rendering doesn't suffer from that limitation. From the sentence I don't understand if the 75µV limitation is normally done to count Slow-Wave Sleep or removing the limitation allows this data plot to enhance the visualization of Slow-Wave Sleep because even low voltage signals are worth visualizing. Not sure I am following.
In order to score SWS, the delta waves need to be at least 75µV high. This cutoff ("IMHO") was chosen arbitrarily. SWS amplitude decreases as a function of age. Consequently, older people may have frequency-qualifying SWS, but it is not counted because it does not reach height requirements (insert Disney ride one-liner here). So they are told that their SWS may be like 0%, but in fact, they may have a whole bunch of Really Solid Sleep (RSS). In this new method of looking at sleep (from henceforce to be called Muffinalysis) one can make up their own interpretion, and call RSS whenever they want.
SleepWrangler wrote:To truly analyze sleep do you need to visualize to all 10 20 placed electrodes? So you would need multiple layers of these visualizations to get an overall picture?
The recommended derivations are:
Generally, one looks at the sleep-wake transition in O2, SWS in F4 and overall sleep in C4. OTC sleep "analysis" (Zeo, etc.) tends to look at the frontal zone).
To "truly" analyze sleep, you also need EOGs and a chin EMG.
SleepWrangler wrote:NA Data Analysis appears to be a data mining but I need a bit of help. Google link would be nice.
When the Polish guys release their product later this year, they may have something (I don't know how deeply (SWS humor) they're going to get into it, tho). Muffinalysis will be sorta made up as we go along.
Meanwhile:
https://www.google.com/search?q=sleep+s ... 1085&dpr=1
SleepWrangler wrote:Would the Sleep Scoring Rules operate across each of the EEG sensors or are these normally preprocessed into some other standard data stream?
See above re: "traditional" sleep scoring.
Will fiddle with multiple channel analysis to see what shakes out, however, I think if they're simply combined into a standard (common) output, a lot of stuff would attenuate out.