EEG pattern of openED hand vs closED hand compared to openING vs closING

ZimtCremeZimtCreme Malaysia
edited July 2015 in Research
Hi,

I have read into EEG control for robotic arms/hands for a while now. Most of them do recording of the opening and closing of a hand aswell as the rest state.
I have not yet seen papers reporting an opened state vs closed state and rest state for the hand. Considering there are studys for opened vs closed eyes, why arent there any for the hand?
Any ideas where the differences are to be expected? Could it be used for control of robotic hands?

If i just havent found papers using it, or even comparing both aproches, please let me know.


Regards
Zimt

Comments

  • wjcroftwjcroft Mount Shasta, CA
    If there is no 'intending' to move or actual motion (or applied static pressure), then there is no way to differentiate opened vs closed. I'm not sure about your hand, but I can be perfectly relaxed with my hand either opened or closed. So the EEG is going to be the same in both cases.

    Yes, there is some differentiation in the proprioceptive / sensory conditions in opened vs closed. But those don't show up detectably at the motor strip.

    With the opening / closing of the eyes, there is a shift in alpha; which is easily detected.
  • ZimtCremeZimtCreme Malaysia
    Unless held by an external force, my relaxed hand has slightly curved fingers, sort of a halve moon shape. Keeping it open, so that palm and fingers form a straight line, or holding it in a fist, does require some effort. I think thats what you mean by static pressure? Would that show in EEG? Or still not enought to detect? 

    Thx so far
    Zimt
  • wjcroftwjcroft Mount Shasta, CA
    Zimt,

    Keeping it open, so that palm and fingers form a straight line, or holding it in a fist, does require some effort. I think thats what you mean by static pressure? Would that show in EEG?

    Yes, holding a fist or open palm does engage muscle groups, so may be detectable. You'll have to check the research papers. 

    Use the search box at lower right for "EMG", some users are controlling robot hands with EMG, but I don't know what kind of resolution is possible. Also checkout what Dean Kamen is doing.

  • ZimtCremeZimtCreme Malaysia
    I do see the EMG signal differ between relaxed, and static force. But will the EEG show? And how will that compare to EEG of movement?
    Regards,
    Zimt
  • wjcroftwjcroft Mount Shasta, CA
    Zimt, hi.

    Checkout Jeremy @jfrey 's post on motor imagery using OpenViBE and 16 channels,

    http://blog.jfrey.info/2015/03/03/openbci-motor-imagery/

    Also, I believe I read on some of the links for the Dean Kamen search (previous post), that their 1st generation arm uses EMG. And that took significant effort and years to develop. Now for their 2nd gen arm they are going to try EEG activation (or cEEG, direct cortical contact EEG), but again they expect considerable R&D to get there.

    https://www.google.com/search?q=bci+motor+imagery

  • ZimtCremeZimtCreme Malaysia
    Hi,


    Maybe i'm wrong, but i think your advice is to start with EMG instead of EEG.
    Wouldn't work, since i don't call the shots :), but it has been sugested

    First article is a nice read and reference. Might adapt parts of it for different hard and software.
    Once thing though bothered me, when it says fingermovement is next to impossible by EEG. Even though it doesnt match ECoG, it has been done
    http://journals.plos.org/ploscollections/article?id=10.1371/journal.pone.0085192

    original question remains: Why no tests with different hand positions, rather then movement? While i do understand that ERD/ERS play an important role, cant there be something extracted from the state itself aswell?
    ...had an article reading fingerposition via some brainrelated signals cross me...should read, will let you know...

    Zimt
Sign In or Register to comment.

© Vanilla Keystone Theme 2026