issues with my 2 Cyton dongles / speller apps [resolved]

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Comments

  • wjcroftwjcroft Mount Shasta, CA

    You say "very very bad", do the plain Ultracortex dry electrodes work any differently? It is a well known fact that wet electrodes always give somewhat higher amplitude signals than dry.

  • etcetc Italy

    Sorry, I didnt'undesrtand "do the plain". In every case, Ultracortex dry electrodes work very very bad.
    The Openbci wet electrodes are very very better. And I read some researches with openbci and the electrodes were always the wet ones.

  • wjcroftwjcroft Mount Shasta, CA

    PLEASE try the MindAffect cVEP based speller instead of the very old and unmaintained OpenViBE P300 speller. I am almost certain you will find it faster and more accurate.

  • etcetc Italy

    Thank you! You gave to me this suggestion(Mindaffect) and I wrote a email to get informations.
    The mail is sent on 5/3. I didnt'get any answer.
    With the p300 Openvibe Xdawn,
    Openbci cap and wet electrodes I wrote a word!
    For the moment it is better Openbci cap with wet electrodes and Opnevibe!!!
    Thank you very much! You are always very gentle!

  • wjcroftwjcroft Mount Shasta, CA

    The complete MindAffect open source package is available at the previous link I gave. It is being actively maintained. OpenViBE speller is NOT supported or maintained. Additionally the cVEP (code based Visual Evoked Potentials) speller uses signals that are MUCH stronger than the P300. Meaning they should be received easily with the ThinkPulse. Only 4 channels are needed.

  • etcetc Italy

    Thank you. There is a colossal difference cVEP vs P300; for the first it is necessary the training of the disabled person; for the second no. The first asks a perfetc control of the sight; the second no.
    I think that if Thinkpulse is very bad, but very very bad, I have to change ... Thinkpulse not the whole system.
    Thank you!!!

  • wjcroftwjcroft Mount Shasta, CA

    The MindAffect is far superior. Any training required is easily accomplished. VEP signals are by nature much stronger than P300.

    The first asks a perfect control of the sight

    No, this is not true. In addition to the virtual 'computer' keyboard link I gave, the open source allows very simple 'keyboards' to be constructed, of your own custom design. For example, it might only have 6 or so selection boxes. Or the selection system could have nested levels, etc. The cVEP response is based on what you are placing your attention on. NOT on your precise eyeball or head position. One of the newer demo videos shows the subject turning their head towards the selection. This was a goofy choice they made on that video to make the letters selected appear more authentic to the demo video viewer. In fact, only attention on the letter or box is required.

    In addition to stronger signal, cVEP offers much faster selection time. With P300 quite a few trials are needed to improve signal to noise ratio via averaging. This is not the case with cVEP.

    I'm not sure we should classify ThinkPulse as "very very bad" until we have some more specifics on what is failing for you. It does deliver a decent EEG signal.

  • etcetc Italy
    edited March 9

    I'll give a look to Cvep solution.
    Thank you!!! You are always gentle.

  • etcetc Italy
    edited March 9

    I read. With the Cvep solution the disabled person HAVE to look at letter that he is thinking. If he wants write "Dad", he have to point first D, then, in few moments, A, then, in few moments, D.
    In other words, he have to point in few moments to 3 points.
    I dont't know if it is good for Laura. But...
    Thank you.

  • wjcroftwjcroft Mount Shasta, CA

    With the cVEP solution the disabled person HAVE to look at letter that he is thinking. If he wants write "Dad", he have to point first D, then, in few moments, A, then, in few moments, D.

    I guess I don't understand what P300 speller you are using. Don't all spellers have some sort of 'keyboard' that you look at? (The OpenViBE speller has this.) Typically the rows and columns of this letter array light up 'randomly'. Then when the subject's desired letter row or column lights, the oddball P300 response is generated.

    So my impression is that ALL BCI spellers have a 'keyboard', in which the subject places their attention or desire on the letter they are requesting. You use the word 'point'. I believe the more accurate word would be 'attention' on the desired letter.

  • etcetc Italy
    edited March 10

    But, in the P300 speller, the target letter flashes 15 times (it is possible to get averages) and if the persons looks at another letter for a moment it is not a big problem because doesn't start the p300.
    With cVEP the person HAS to look every letters in that few momentes. The work of cVEP is made, before BCI, with systems for disabled people where there is a Camera that looks at eyes of the person and undertstands what letter the person is pointing.

  • wjcroftwjcroft Mount Shasta, CA

    MindAffect is open source, and I'm certain they have a user configurable setting or variable that determines the number of milliseconds required to pass threshold of detection on a key press detection. This setting could be adjusted from 100's of ms, to 1000+ ms or beyond for those users who need the interface to respond slowly. Because of issues with their ability to focus / pay attention.

    P300 signal is so noisy, signal averaging is REQUIRED to bring the signal out of the noise. Please don't write off MindAffect as 'impossible' or unworkable, unless you have actually tried it and configured it to perform as you require. MindAffect is a supported app. OpenViBE P300 speller is unsupported and unmaintained and dropped from upgrades.

    If you have questions, and their email response is slower than expected, you can always create an Issue on their Github.

    https://github.com/mindaffect/pymindaffectBCI
    https://github.com/mindaffect/pymindaffectBCI/issues

    MindAffect cVEP has nothing to do with the eye tracking camera setup you mention. It is NOT detecting 'pointing'.

  • etcetc Italy
    edited March 10

    Dear Wjcroft, you were always gentle!
    I will that Laura can communicate! I am at few steps to test P300 with her. I have not problem to try also another solution!
    I tell more: I am happy because there are more than one solution. So I can hope.
    Think to one thing: any solution asks a lot of activities: I am not young, and I am not a young programmer. I am an old system programmer, I worked with IB M System, with Cobol. Not with the new languages. Now, for every possible solution, I have to choose the new hardware (not always!) , I have to buy it, and it comes from a far Country, not always works well... . I have to download software, not always it works well (on Openvibe I found 2 bugs and now they are fixing them); I have to write to the forum of the open software, I have to write a bad but not a too bad english text; I have to hope that someone answers, .... . The software requires other software: I have to download these other softwares; some of these doesn't work and ... ; loop!. I am not buying a washing machine... : turn on and go!
    These words to tell you that it is not easy to test a new solution! But Laura is the most important thing for me.
    Thank you!

  • wjcroftwjcroft Mount Shasta, CA

    Great, keep up the good work. I'm only mentioning MindAffect because it is the most impressive BCI speller I've ever seen. You may be just fine with the OpenViBE P300 speller. As you mention you've already had to tackle OpenViBE bugs, which can take much effort and coordination between programmers to solve. Especially with unsupported OpenViBE apps such as spellers.

    You may also have some misconceptions about MindAffect or how complex it is to setup. The tutorials are right on their Github page.

    Regards, William

  • etcetc Italy
    edited March 10

    ps is as camera beacause the person has to look to the target letter: with BCI CVEP this is understood analyzing the waves. With the Camera, is the Camera to understand.
    Thank you for your suggestions!

  • wjcroftwjcroft Mount Shasta, CA

    Thanks. With P300, the subject still has to place their 'attention' on the desired letter, watching the rows and columns it is in, light up, 'randomly', along with other unrelated rows and columns. So in both cVEP and P300 spellers, the subject has their attention on the desired letter.

  • etcetc Italy

    No, not in the same manner. With cvep you have to look one letter; if you look another letter, the system undestand that you want write the other letter.
    With p300, the p300 wave goes up, if works well, only if the letter is the target.

  • wjcroftwjcroft Mount Shasta, CA

    No, not in the same manner. With cvep you have to look one letter; if you look another letter, the system undestand that you want write the other letter.

    As I said previously, it is VERY likely that the source code for MindAffect, has a user adjustable 'threshold' in milliseconds, that requires the subject place their attention CONTINOUSLY on that letter for that length time, for the letter to register. Any momentary glancing at other letters would reset this timer. Does that make sense? Perhaps my English is not coming across. You have total source access with MindAffect and such adjustments I imagine are common and likely documented.

  • wjcroftwjcroft Mount Shasta, CA

    I don't want to discuss MindAffect any more. You are welcome to explore it at your leisure.

  • etcetc Italy
    edited March 10

    Thank you. Also for me. My English is certainly bad. I wrote to this forum because I had a problem whit the Opnebci Dongle...

  • etcetc Italy
    edited March 10

    ps I'll try cVEP; I can do it with openvibe: there is something similar. But without problems (downloads, etc...)
    ps2 how does openbci connect to MindAffect? Has MindAffect a driver for openbci?

  • etcetc Italy

    Thank you!

  • etcetc Italy

    Hi William!
    I got from Openbci a one time discount code for a new Dongle. Thank you!!!
    I’m using this post to ask to you some other questions. If you think that it is not the right place, no problem!
    Now, I would buy other items to pay only one delivery.
    The questions:
    1) I have not a good idea about the dry electrodes…; but I hate the gel and I am always ready to change my opinion. What do you think about the Openbci EEG Headband? How do these dry electrodes work? Maybe the dry electrodes put in this headband can work better?
    2) If I work with the gold cap electrodes, can I use the ear clips of the Ultracortex headset for the bias and srb connection to Cyton? Or have I to use necessarily 2 gold caps electrodes for the earlobes?
    This is to reduce the use of electrode past and medical tape!
    3) I read in many pages of the Openci shop a suggestion to use rechargeable batteries; for example this one: https://www.adafruit.com/product/1578.
    The question: does this item connect to the Cyton as the 6V AA battery holder (in the same manner)?
    Thank you very much!
    Ettore

  • wjcroftwjcroft Mount Shasta, CA

    1) I have not a good idea about the dry electrodes…; but I hate the gel and I am always ready to change my opinion. What do you think about the Openbci EEG Headband? How do these dry electrodes work? Maybe the dry electrodes put in this headband can work better?

    Hi Ettore,

    You stated previously that ONLY the wet / gel electrodes worked for your P300 Speller. This is (likely) because signal amplitude and quality is somewhat better with the wet skin surface interface. So... ANY type of dry electrode will generally not do as well compared to what you are getting with the gel. As I mentioned previously, your dry active ThinkPulse electrodes may work adequately with the MindAffect cVEP. Additionally if you study the MindAffect material, they use a custom printable headset, based on water (or saline) alone; using a small sponge soaked in water. No paste or sticky gel. So cleanup is very easy, no cleanup needed.

    If you were to rank the electrodes by maximum signal amplitude, I'd probably say:

    • gel / paste / wet / saline
    • ThinkPulse (which are dry active electrodes)
    • then the dry passive electrodes (used in the default Ultracortex or headband you mention.)

    2) If I work with the gold cap electrodes, can I use the ear clips of the Ultracortex headset for the bias and srb connection to Cyton? Or have I to use necessarily 2 gold caps electrodes for the earlobes?

    The Ag-AgCl ear clips should work ok (no paste needed) with the gold cups on the head. But note because the ear / reference side of the connection is dry, signal may be slightly less. I would avoid putting any paste on the dry ear clips, as that will be both messy to clean, and may shorten the coating lifetime.

    This is to reduce the use of electrode paste and medical tape!

    There ARE special ear clip EEG electrodes, which consist of TWO cups facing each other; then filled with paste. You can find these online.

    3) I read in many pages of the Openbci shop a suggestion to use rechargeable batteries; for example this one: https://www.adafruit.com/product/1578

    Yes, the Adafruit lithium cells are widely used with Ultracortex and Cyton. They also sell chargers.

    The question: does this item connect to the Cyton as the 6V AA battery holder (in the same manner)?

    Same connector.

    Thank you very much!

    Regards,

  • etcetc Italy

    You are an angel!!!

  • etcetc Italy
    edited March 15

    I gave a new and more deep look to Mindaffect. Much interesting!!!
    But...
    I would say to you where I see some big problems (not cVeps vs P300): I am understanding that I would be able to do things that I dont'know if I am able to do. In the first 3 rows (only the first 3) I read that:
    1) I must have win10;
    2) I must have JDK;
    3) I must have a 3d printer;
    4) "pip install -e ." ???
    And for the other 500 rows what I have to do?
    Openvibe: I download the software and have not more to do.
    I think that Mindaffect is made not for the final user, or for an old programmer (IBM, Cobol, etc...). I think that Mindaffect is for persons with experience, a good experience in the new languages, in the hardware, etc... .
    Am I wrong?
    And sorry for my bad English! I hope that my idea is clear the same.
    Ettore

  • etcetc Italy

    Only to say that I made a new order for some items and I got the discount "ETC" that you gave to me.
    Thank you, William!

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