Friday, August 28, 2009

Neurosky - EEG for the masses!


The allure of dry sensor technology & a wireless EEG headset had me ordering a Neurosky unit. I was concerned about quality because I wondered how good a unit that costs under $200, whose target audience was gamers would be. The least expensive EEG competitor (assembled) is well over a thousand, and does not use wireless nor the dry sensor technology. This is my review of the unit after having used it for a week. Note that my only other experience is with the Open Source EEG unit, which works quite well, but has to be built, and whose component costs are in excess of $200.

On a visual inspection the unit looks like a set of high quality headphones with an extra arm attached, that might be mistaken for a microphone. The arm contains the sensor that rests against the top of the forehead. It is far lighter that I expected which is a good thing. The headset is adjustable & very comfortable to wear. On the left ear foam there are 3 sensors that are meant to contact the ear, which gives the effective ground. A bluetooth dongle is included. So mechanically, & appearance-wise I was very pleased. Not sure how susceptible this may be to electostatic discharges (I suspect the worse considering the micro-currents being measured), but so far so good...

Neurosky includes 'brain visualizer' software with the unit that is done using a polar coordinate type of display. I was a little offput by this initially and thought about writing an interface for BrainBay, which is an open source application for viewing EEG. Normally I prefer to train in just two bands at a time. But I made an interesting discovery that has me prefering Neuroskys display, and this relates to a fairly serious mistake I made in my training with BrainBay. For several months I trained to reduce delta, and increase the high alpha. In suppressing delta I believe I was also unknowingly suppressing theta, which is the bandwidth directly below alpha. According to some writers, a healthy theta component with the alpha component gives the most effective meditations, and helps in being able to utilize the subconscious to solve problems. The picture at the head of this blog is a capture of the Neurosky BrainVisualizer view showing an unfortunate 'notch' in my theta waves, along with the desired notch in the delta. In posts to come we will see how long it takes me to get rid of this 'notch'.

Using the unit is simplicity itself, and I find myself prefering it over my OpenSource EEG. When you put the unit on & start the software there is a 'signal strength bands' that show whether or not the unit is capturing. Now if I have been outside and am the least bit sweaty, this works great. Normally I have to moisten the areas the 'dry sensors' touch to get a good signal. No doubt this varies from individual to individual. After using it I always clean & dry the sensor areas.

The BrainVisualizer has an interesting delayed time component that allows you to see the change in the polar display over the last few seconds. The old traces fade out, and the new ones show full intensity. This is a really nice touch that gives a quick idea of your trend. There is also a color change that it rotates through that has no purpose other than eye candy (at least as far as I know). This display works very well not only for giving your attention to just a few bands, but the overall picture of brain waves being generated.

There are also meters on the side for 'attention' & 'meditation'. When pegged at 100% they commence doing an interesting flash sequence. I noticed I can get a flashing 'meditation' without any theta component, so I guess the developers did not feel that theta was a necessary component. I wish Neurosky would publish on what they were thinking.

So whats missing? I would like to be able to record and then do averaging on the session. Neurosky provides developer tools for free, so it may be possible to do this addition. I have not tested for calibration but may attempt that in a later post. As a single channel EEG, you will not be able to look for brain synchronicity, other than that it has few limitations & great convenience.

As an EEG unit for under $200, this should make people very happy. I am certainly pleased & plan on purchasing some additional ones as gifts.

7 comments:

  1. Interesting read. I bought a mindset myself, and am a little disappointed. I find that my readings tend to fluctuate quite a bit for very little reason. I also find my self with little use for it, due to the lack of compatable programs.

    I'd love an entrainment program, but I wouldn't know where to begin programming one, or where to begin making an existing one compatable with the mindest.

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  2. Hi folks, I'm glad to know that other people can be found here to talk about the Neurosky Mindset use. Even if the device has some flaws to solve (see their website forums), it's quite a good quality EEG indeed.

    Well, these are some observations that I have found useful after one week of use, and also some prior experience with other biofeedback devices. No doubt I'm just a one week beginner, and much of what i may say is just anecdotic observation, but I feel like these anecdotes may help others. At first I was quite lost on what to do, but things started to go much better afer trial and error!

    1) To get started, check that you have low RF interference. If you have a laptop, you are blessed to be able to move and find a good spot, otherwise, try shutting off everything else in your room. You may do the experiment with your main house electrical switch and see the miracle happen as long as you are careful in general terms so you do not disconnect something important over there!. You may like to play getting far and near from certain electric noise sources to check what can be better solved like this. I have found that the last meter (purple gamma) is quite important for this. All EEGs are subject to this noise, even the best. If you can't move (desktop PC), don't panic, very soon this wil have some softwares compatible with the smartphones. BTW, check Ocz Nia forums and video for this same stuff. Anyhow, the grounding on my case didn't worked well. Location is key. One note of observation: Looks like we are bombarded by strong AC freqs that are even stronger than the brainwaves themselves! Maybe this inexpensive eegs will act as proof about the problem and raise a new global awareness about this invisible pollution! Or am I just exaggerating too much about the relevance of this problem? BTW, I'm not an expert at all on this anyway, I'm just asking to see if someone may answer more technically... answers appreciated.

    2)You obtain higher meditation and concentration levels at the beggining of the sessions. Just like with muscles, you get tired over time (but faster), so it's difficult to make the meters be at 100% over some minutes. Yes, it's not only your bad luck or wrong "paranoid" idea if you don't repeat early high levels later within a session. I have found that this has helped me this week to understand my real biorythms and try to dose real world activities with intermediate time spaces within, so it seems like a good thing to better understand oneself.

    3) Higher levels are achievable with practice over time (different sessions). That's how biofeedback works, and I'm just starting, but I already have some improvements on this. At first I was a bit skeptical, but i have found that this works really as said in web literature. Or is just initial placebo effect?

    3) I get a really high level of meditation meter when I close my eyes, but only somoene else can notice it as there is no sound regarding the meters, and as soon as you open them, it vanishes. Or you can record the screen it w/a vid soft or watch someone else using the EEG. Closing eyes should make the both alpha levels go up, and this makes sense according to literature on EEG.

    4) I get somehow higher levels on both meters when I visualise some pleasant physical activity, like bouncing a basketball or swimming backwards. Somehow more attention if the visualized activity is faster, and meditation with slower visualization movements. Looks like visualizing taking a coffee aso works. Apparently open eyes and doing nothing at all makes them go down.

    5) It's easier to have either one or other meter high if you switch between them, like switching car gears with high RPM, so you loose less power than if they both go too much down. I had read before, that top sport players before a movement like shooting a ball have strong alpha (meditation, relaxing mind BUT with some pleasant activity) and seconds before doing it, they do stronger beta (attention).

    I will post next to this one because I exceeded the allowed length...

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  3. 6) Too much concentration for too long feels stressing, too much meditation is like start day dreaming. The right moment for switching is really important to feel good. As Gary said, I have felt more in the zone at will, but a good timing is important. As Gary said, deep theta meditaion (or sleep) looks like not covered by he meditaion level meter, this might be another important level to look for, just taking a look at the theta meter could help. I haven't done this yet.

    7) I get stronger levels after keeping a steady breathing with 10 seconds length (5 in and 5 exhale), and I can keep less tired my mind, both according to EEG meters (longer time) and subjective terms. This actually has a physical reason to be like this. The heart works better at this speed. If you have a heart monitor grapher, likewise the wild divine or freese framer, it's really interesting to see all the graphs at the same time, if not, you can get a free breath pacer called "Smoooth DBA". Really recommendable, but remember to use your belly more than throat for better breathing. Knowing how much pressure to exert is also important.

    8) I have seen that if you adjust the settings of the mentioned breath pacer in "special modes" you can really switch faster from one meter to the other. Inhaling faster and ex slower is soothing (meditation meter), and all the way around is energizing (attention). This really works for me.

    I'm starting to enjoy this device. Please write any thoughts on how to use it, I'm just starting to learn to use it, just as you all!

    Good idea this blog, Gary. Hope to hear something else about that brainbay port and any other developments! Your related video on other website is very interesting too. I also hope as you do, that we may find better ways for using this element for wellbeing. I also bought it for these reasons.

    Nyquil Driver: have patience pal, but don't over do it! I’ve found that 15 minutes once or twice a day is ok for me. About other games, check Airheads and Space invaders from Roll7 on youtube. Apparently, they will release those games later on this year.

    Also there is other blog from other mindset user over here:
    http://www.thetaobums.com/index.php?s=0aef9b36d2594dc327d3ef255293ee75&showtopic=11135&st=0

    I hope this may help

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  4. Well, I have continued to use the Mindset and I have validated most of my initial thoughts, actually doing good improvements in the practice.

    The last post from Gary on September the 9th makes a link to an online paper that is truly worth reading for anyone serious about using EEG for wellness.

    It is a good point that I wasn't considering so strongly, that if you first don't supress low theta and reward smr enough, a too deeep meditation leaves oneself quite sleepy and drowsy. That may be what it is called a "bad meditation". Afterwards, when one has rteached enough beta activity, it seems as logical to try lower frequencies, starting by aplpha. Right now I feel I'm am only on this first stage, and it's helping my daily life by making me less distractable. I just practice some alpha from time to time as a refresher. In my personal case I have always had some distractability, so improving attention in the long term is one of my goals.

    Secondly, I found recently a natural technique for increasing my attention level. I figured out as mentioned before that the attention level tends to fall within a session, but here is a way besides those mentioned before, to retain a high attention level longer in time:

    Instead of looking at the visualizer screen with the same head position throughout time, it is good to switch after 1 minute, still looking at the screen, but from a diffent head angle. It seems like when you do that, you start to use a different portion of your brain, and the attention meter is reached to 100% more often. Doing this with all head angles makes a truly refreshing feeling and besides that, the attention score goes several more times to the top within a session.

    It feels at first like odd, but afer thinking about it a while, I arrived to the conclusion that this is the way in which it was intended to work the human brain in a natural environment. Our ancestors were people that mostly travelled around all day "looking" for food or other things in all directions, and only very recently with the introduction of books and different sorts of screens, we stay hours and hours looking something with the same head angle and eyes in a fixed position.

    This EEG mind enhancement exploration seems like quite interesting and useful this far.

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  5. I am very curious about any studies or peer reviewed journals featuring NeuroSky (or any other inexpensive eeg with limited contact points.)

    I am a university student writing my thesis on neurofeedback and its application for a home meditation practice. If you all know of any information that I could site for my thesis I would be very grateful.

    I am also looking for a grant so my school can purchase on of these (or similar) devices for our own meditation studies. Which device would you all suggest for meditation practice specifically?

    Thanks so much,
    -J

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  6. Neural Music Production and Performance
    http://www.youtube.com/watch?v=j1NJJd8N4bE

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  7. EEGID is an app for android to work with the bluetooth version to actually record raw data if you are interested in doing real research. https://play.google.com/store/apps/details?id=com.isomerprogramming.application.eegID&hl=en

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