EEG and other ways to detect arousals?

[BB63]

I have found some answers to some of my sleep related issues thanks to the volunteers/users of this forum and the use of a datalogging CPAP with OSCAR! The change in my sleep has improved markedly!

However, the issue of detecting arousal(s) is possibly limiting my progress towards good sleep-I'm still not sleeping well and find myself now wondering if I am experiencing significant arousal(s). But, I don't think datalogging CPAPs can detect an arousal, at least not directly or with an adequate degree of confidence.

So, I have been studying EEG. EEG measures brain activity noninvasively. EEG sensors are the little suction cup like objects that get glued to the skin during a professional sleep test. Besides brain activity, they detect electrical stimulus from the body that are generated when muscle moves. So, they can detect eyes opening (arousals or REM sleep), motion in the hands and legs*.

In the course of my research, I found a product that might be of use to those members who wonder if they have arousals, which destroy deep sleep and make us feel so tired, even when apnea events are being minimized by the CPAP. The product is a USB EEG sensor, it's only a sensor though, not multiple sensors like we use at lab grade sleep studies. Ideally it would be nice if they could plug into the CPAP so that OSCAR could access their data via the SD Card. Still, they should be able to detect eye, leg and arm movement which would provide the answer to the question regarding whether the patient is suffering from arousals or not.

The portable USB based EEG sensors (and other types of sensors BTW) is at:

[Commercial Link Removed] Search adinstruments for "sensors"

While using these sensors every night would be inconvenient and perhaps not practical, they could be used occasionally to help in determining why the patients sleep is so poor. Interfacing these sensors into OSCAR should be no more difficult than interfacing an Oximetry unit.

I'm curious, how many users here would like to know if they are suffering from arousals? I know I sure would like to know! Just a thought.

AB

*Note that MEMS based (nearly microscopic) accelerators could also be used to detect arm and leg movement, but NOT eye movement.

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[ardenum]

Where are the electrodes? What about the software?

Doesn't look very useful. Try OpenBCI if you're interested in something that works.

[BB63]

I was not aware of BCI, it looks very good at first glance!!

When I did my initial study, I wasn't looking for a full blown multiple transducer/multiple channel recorder though. My idea was to use a single channel unit, such as the unit I referenced. I do not know if the company has software for capturing the usb raw data or not. It's likely they do however. As far as software for viewing the raw data, use the company's program to recover the raw data, cut and paste it into a spreadsheet and use the spreadsheet's plotting/plotting capability to view the data in a graph or plot.

The BCI unit appears to offer the whole 9 yards, just as the professional sleep labs use when they do a full sleep study. My thought was a more cost effective unit that an individual could afford.

Many details are not available as the product will only be released in October. For me, the question of whether I am having arousals is a burning issue-so I began searching for a single sensor solution. If is isn't to pricey, I will probably buy one for myself. Or, I might roll my own, analog to digital converter PCB's are available on that auction website cheaply. So, a set of electrodes, a small battery and signal conditioning/amplifier hardware would provide a solution. Or, skip the digital completely, grab the analog output and feed it directly into a smartphone audio recorder or into a PC's soundcard. In the case of an all analog to PC system, Audacity (open source audio editing and display ap) would be my friend.

AB

[Illorum]

Sleep quality is a lot more complicated than just AASM defined "arousals" - there's Respiratory Cycle-related EEG Changes, the Cyclic Alternating Pattern, Slow Wave Sleep %, etc.

You could try purchasing the research version of the Dreem 2, which is a dry EEG headband that is sensitive enough to detect arousals, though this is pricey and would require you to know how to score EEG arousals, which is not something that is very easy. If you are trying to see if you're having RERAs or something of that sort, the best way is probably by measuring Pulse Transit Time with Photoplethysmography. This paper is a great read and goes in depth on it.

[BB63]

TY info Illorum.

I had to supply a password, so I didn't have access to the discord website. But the article is very comprehensive, ty for that info as well.

I did learn about discord from independent web resources. Needing their software and to pay a fee is outrageous and sent up a HUGE red flag. It appears to be social networking, though it is whitewashed from the outside view. I don't allow any software to run on my computer unless it is open source.

See security info below*, if interested, it's OT for this forum and is secondary to this post.

I did much reading in other articles found with the buzzwords s you gave though. And, it's times like these when I realize just how complicated the sleep topic is and why sleep doctors can't just snap their fingers and fix sleep issues!

I will likely never be able to interpret EEG data in detail, as you say...."how to score EEG arousals, which is not something that is very easy." However, I have read enough to know that a single EEG sensor displays signals that can be very distant from the sensor itself-and that the strength in EEG comes from comparing multiple/network EEG traces to to each other in the same time domain.

Some significant improvement in my CPAP settings have yielded much better bodily responses (OSCAR traces for me looks much better these days!). However, my sleep is still very unsatisfactory and I suspect strongly that deep sleep is eluding me due to arousals! My motivation for my knowledge quest regarding arousal indicators is ongoing! The eyes are problematic, so sensors to detect REM sleep entry will probably be limited to EEG. But, we have have nearly microscopic accelerometers using MEMS technology, they are dirt cheap and provide positional information as well as acceleration information and they use very little power! An accelerometer placed on the legs and arms can indicate whether arousals are happening, hence my interest in accelerometers. Because accelerometers are 3D, they can also be used for determining the position of the person as they sleep-many of us have to wonder if we have positional related apneas.

Again, TY info, it is very good to know!

AB



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*I do have a bullet proof system (32 GB ram, running from a CD), which does allow me to view websites such as discord. A CD loads the basic operating system and the CD cannot be written to. The entire operating system is loaded into ram, and a file from a ram stick issues commands for fully updating the system, including the new software.

After the update is complete, I have a bullet proof system, though the update takes about an hour to complete. But, I have a system with no personal info on it and changes made by hostile websites or hackers trying to infiltrate it are thwarted. So, it's not trivial and it's only practical for high risk sites such as discord, google, yahoo, facebook, twitter etc and other entities that use active content to extract personal information from my system in stealth mode.

It is of course impossible to avoid tracking-google has tracking utilities and paid sniffer nodes, which report back to goodle with data they harvest from traffic passing through these nodes. And, all ISP's report times and dates of their users ISP addresses/changes to google, so google always knows which user is associated with which ISP address-even if dynamic IP addresses are used.

When I am done with my bullet proof system, I simply SHUT IT OFF with an asynchronous master reset and all the data in ram is gone, even though the web sites I connected to or the third party software I might be evaluating have planted forever cookies (also called 'ever' cookies) or made changes to system files. I call it my bullet proof system, it's my "ULTIMATE SANDBOX".

[Dormeo]

The big question is what you would do with the information if you had it.

It's conceivable you would spot other correlated data that would help you understand the causes for arousals, but that is fairly unlikely if the arousals are not related to respiration.

You might also be thinking of a way to quantify direction of change: improvement, steady state, decline. But I think you will get a better sense of that by carefully noting how you feel during the day. Keeping a journal with brief notations can be a very helpful tool.

But there may be possibilities I'm not thinking of, so my question is truly an open one.

[slowriter]

You could try purchasing the research version of the Dreem 2, which is a dry EEG headband that is sensitive enough to detect arousals, though this is pricey and would require you to know how to score EEG arousals ...

One could also use the regular Dreem 2 and use it's sleep staging to look for general evidence of fragmentation, rather than specific arousal points. Barry Krakow, for example, has suggested the REM Consolidation Index (time in REM/number of REM stages) as a reasonable metric for overall sleep quality, and you can track that data with the Dreem.

The Dreem, BTW, generally only scores arousals that last more than two minutes, but it will also indicate those that are less (though I don't believe it can do less than a minute).

[BB63]

I agree completely, it is a question of what I'd do with the information if I had it!!

Having the answer would fill in other missing pieces to the puzzle and move me (possibly) closer to my goal of not feeling like crap so much.

I practice Functional Medicine, though I am not a doctor. My GP is interested in Functional Medicine as well, I'm giving him some basics in it. Functional Medicine considers the body as a SYSTEM-they don't look for the cause of a belly ache in the gut. They prescribe diet changes when appropriate, food in by far the best medicine! They are far more likely to prescribe supplements vs expensive pharmaceuticals that only address a symptom.

To answer your question more precisely and specifically....I'd first review an experts testimony (I have on tape) regarding exactly how the brain controls or influences sleep. The are 3 major components of sleep and all 3 are controlled by 3 different colocated parts of the brain, brain located at the base of the brain stem and just outside the blood-brain barrier. One of them controls paralysis during sleep, the second one is memory while asleep. I forget the other one, which is why I would review the video record I have. The author of the video was plagued with leg tremors and lag pain for no apparent reason, she treated herself and eventually ended her leg tremors. From there, I might request blood work or the equivalent of it by spectroscopic analysis of blood cells on an atomic scale and I'd study in more depth the parts parts of the brain that control/influence sleep. The chemistry of what's actually in the cell is far more important than the contents of the blood serum...albeit more costly to access. Conventional Medicine Practitioners, in general, still consider looking at what's inside the cell as ridiculous and science fiction-though there are exceptions::>

Related Question:

Question........A middle aged otherwise fairly healthy man gets up early to go to the doctor with his wife. He has coffee, breakfast and otherwise does his typical morning regimen. He gets to the doctor with his wife, but keeps asking over and over again for breakfast and coffee! So, what's wrong??

Answer......the man has a sleep Disorder!!! He's still asleep even though he is walking, talking and coherent! He has a chemical imbalance that is suppressing his extremely short term memory. This type of memory loss should only happen during sleep!!!! And, it is this memory suppression that is the reason why we (forum members) don't remember arousels even though we are often times fully awake in bed.

The point of all of this is that I might not have a sleep issue  issue at all, even though I feel like crap! BUT THE GOAL IS TO FIND THE CAUSE, not to treat symptoms. There can be many other causes that aren't in the brain or in my legs or rooted and related to arousels at all. So, determining if I have arousels or not is more than superfluous information-and the answer might send me in a different direction.

Hope that helps, sorry the reply was so wordy.

TY for posting on the topic, additional input is always helpful and many times it's PRICELESS.

AB

[BB63]

Thanks Slowriter. The Dreem 2 is a cutting edge device, worthy of further consideration!

I would be surprised if it had more than one electrode/preamp circuit though-which could cloud it's conclusions that an arousel occurred. A network of sensors is more typical when it comes to EEG.

I remember my first (and only) sleep study in 2005. The technician that hooked me up at the bedside didn't even know what the EEG electrodes worked or what they meant as far as the information they provided. It didn't inspire confidence. I remember asking her why there were only 4 electrodes for my head, which doesn't give much information. She couldn't answer because she didn't know. One of the senior sleep department managers happened to be sitting in the observation room, and later told me the reason though.

I am considering building an array for EEG myself, along with a datalogger-which is quite feasible with today's technology, though the high tech parts needed to preserve noise immunity are pricey. It's a major undertaking though, and interpretation of the results is far from trivial.

I am going to check out the Dreem 2 though, thanks to you and Illorum for bringing it to my attention!

Regards,

AB

[Dormeo]

What you describe are some lines of approach that you might use once you've established that you experience many arousals.   

But you can easily establish that by zooming in on your flow-rate graph in Oscar and scrolling through looking for arousals, which will probably appear as breaths with flow-rates that are larger in amplitude and irregular.  They may be followed by a period of breathing whose flow rate has less amplitude; then a regular asleep flow rate resumes.

I'm attaching an example from a recent night.  (I too have a lot of arousals.)  (Ignore the little squiggles around the zero line between breaths.  That's an unrelated phenomenon called a cardioballistic artifact.)