Cyton Daisy setup for EOG ? [resolved]
DreamBigDreamLucid
CT USA
Hello All!
Writing in regards to adding myoware sensors for eye movements.
I have the Cyton+Daisy setup in combination with the EEG headset to measure EEG signals but I also want to add a channel for eye movements.
In this case, can I use the myoware ribbon directly on the spare channels of the CytonDaisy or do I need to use the Myoware board to interface with it?
I didn't get very good results plugging the myoware cable directly into the C+D configuration.
Thanks!
Comments
Hi Dream,
https://www.google.com/search?q=eog+electrode+placement
If the EEG electrodes are placed in the standard EOG positions with Cyton, you generally won't need to involve the Myoware.
A recent thread you posted,
https://openbci.com/forum/index.php?p=/discussion/2848/signal-quality-drops-out#latest
Mentioned you used the elastic EEG cap, is that correct? For EOG you'll just add some additional electrodes around the eyes. These could be the small adhesive dots used for EMG, or gold cups / paste. If you are doing sleep studies, then the dots may hold on better.
William
William is right that you can use the Cyton+Daisy to collect more than just EEG, if the channel settings are wires are configured properly. Also, it may be more comfortable to use gold cups on the face instead of the Myoware device.
https://docs.openbci.com/docs/05ThirdParty/01-Myoware/MyoCyton
@DreamBigDreamLucid Did you have any issues when going through this Doc?
Can you share some screenshots or screen recording? Can you provide more details on this?
This could help others who would like to use the Myoware + Cyton, though I have never tried it myself.
Take care,
RW
I will run a test tomorrow and post the data and results, I did not save the most recent one. Thanks!
If you skip the Myoware, and just go with the direct electrodes (which I recommend), then these are connected in differential pairs as shown,
Thus these 4 wires do not share the common EEG reference, but instead are configured with the settings panel. To disconnect from the SRB2 bus. Scale factor may also need to be changed. Photo shows a separate ground connection, but you don't actually need that since you have a ground already with the EEG setup.
How would I accomplish this if I am also taking EEG recordings on Cyton+Daisy? My ultimate goal is to take EEG channels, EOG, EMG, and ECG. Can you show how I can add EOG ECG and EMG to the Cyton+Daisy with it setup to also take EEG recordings?
Right now I have:
-Both SRB lower pins connected from Cyton and Daisy via Y Splitter to REF channel,)
-CYTON LOWER Pins
-N1P (gray) to F3
-N2P (purple) to F4
-N3P (blue) to C3
-N4P (green) to C4
-N5P (yellow) to O1
-N6P (orange) to O2
-N7P (red) Not Yet Used
-N8P (brown) Not Yet Used
-BIAS (black) to GND
-DAISY Pins
-None Used Yet with Exception of SRB Pin as declared above.
So, using these extra pins, how can I add EOG, EMG (Chin) and ECG? Any help is greatly appreciated.
The 'N1P' labeling is somewhat of a misnomer. The bottom row of pins is actually labeled: IN1N, IN2N, ... IN8N. The top row of pins is labeled IN1P through IN8P.
You only need 2 channels for the EOG as shown in the photo. EOG is similar to EMG or ECG, in that BOTH plus and minus pins of the channel are used. You then use the GUI Settings panel to turn off SRB2 for channels 7 and 8.
Since you say you need EMG and ECG as well, then you will have to expand to the Daisy channels. Again, these use both plus and minus pins.
https://docs.openbci.com/docs/01GettingStarted/02-Biosensing-Setups/EEGSetup
https://docs.openbci.com/docs/01GettingStarted/02-Biosensing-Setups/EMGSetup
https://docs.openbci.com/docs/01GettingStarted/02-Biosensing-Setups/ECGSetup
Regards, William
Thank you very much for the information; how might the first article differ if I am using the EEG cap in leiu of the singular gold cups? Also, do I need to connect EMG/ECG to the bias pins too? If I do, should I take the bias off the cap to REF or does it not need it because there is already a connection established via the cap?
Is it wrong to have it set up this way per the most recent documentation:
Both SRB lower pins connected from Cyton and Daisy via Y Splitter to REF channel,
BIAS (black) to GND
Reference / SRB2 is the common reference for all your EEG channels.
'Ground' or Bias is used to center the amplifiers and provide some anti-mains injection to reduce EEG mains contamination.
I am a little confused - my EEG cap has a REF ( between PZ and CZ) and a GND (between FP1, FP2 and FZ).
Can you differentiate the instructions based on if you are talking about AGND on the Cyton from the GND on the cap? I think thats where my confusion is.
Most 10-20 EEG caps just have a single site / wire, that is off the 10-20 map. A common location is AFz, which is where your cap places Ground. That is the same AFz ground site used by Electro-cap.
You can use your cap wire labeled 'REF' / Reference for the SRB2 connection, (located at site CPz). OR you can use any other site of your choice. It is entirely arbitrary where Ground and Reference are connected on an EEG cap. You can follow the suggestion of the cap company. Or you can make your own choice.
That makes sense, thank you! One last question regarding the AGND lower pin on the CYTON - what should be connected here? Should this be the GND channel from the cap? Right now, I have the GND channel from the cap going to the lower BIAS pin on the CYTON.
Thank you so much for such prompt responses!
The AGND pin is not used normally. It is only employed if using active electrodes, such as the ThinkPulse,
https://shop.openbci.com/collections/frontpage/products/thinkpulse-active-electrode-kit
Ground on the cap / head can go to any of the 4 Bias pins. They are all interconnected via the circuit traces.
Wonderful William thank you so very, very much!
One last question William, to remove the reference to SRB2 on my EOG (N7 and N8) and my ECG (N9), how do I do this? I go under SETTINGS are "Turn on Advanced, Save, Load, Default"
Found it! Please disregard. Thank you again immeasurably for all your help!