Hi, I start apologizing because I will give any of you that want to help me an hard time.
I am using an EEG device and an alternate current stimulator (tACS).
I have a normal EEG electrode that it is attached both to the EEG amplifier, and at the stimulator, to alternate recording and stimulation, without changing cables
The problem is that when I stimulate the current will flow from the stimulator to the channel and then directly to the amplifier. This will cause two problems:
The stimulation will not flow out to the channel and will not pass to the brain, making all the story pointless.
The amplifier handles brain signals to the range of 1 - 100 milliVolts, while the stimulator stimulates up to 1 milliAmpere. So the impulse from the stimulator coming back will break the amplifier.
My question is:
Can I use arduino to selectively put a resistance between the electrode and the amplifier when the signal is too high. So when I am stimulating the current flows from the stimulator to the channel to the reference of the stimulator (on the other side of the head), and when I am not stimulating the signal is not distorted by the arduino?
I am sorry, I am pretty ignorant about arduino and even the simplest physic behind what I want to do. But knowing that it would be possible to realize this with arduino will push me and my group to put the necessary effort in it.
I hope someone there can help me and I did not broke any rule of the community.. I never read the licence agreements
Thanks, Valerio