31–40 of 44 posts
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But I believe that what kills you is the voltage and not the current.
Actually it is the current.
There are lots of useful applications which should prove at least harmless, if not even beneficial. For example with an EEG sensor you can do neurofeedback training to improve attention, which has been shown to help with ADHD and even epilepsy, among other things. For this purpose, the Neurosky Mindwave Mobile with its low price tag and bluetooth interface is certainly a better choice than any homegrown amplifier. Fo…
Most difficult part of "personal EEG" going forward seems to be the pasting of the electrodes to the front and back of the scalp and the chest. In hospital, someone else does that for you.
I've had a few EEGs and there was never any on the chest. Proper placement would seem to be an issue.
I have been working with EKG on and off for ten years. I helped with this briefly: http://www.neozap.com/freeECG.htm I would love it if someone could produce a more 'rounded' piece of software. I really love my 12-lead ECG machine I got for £10. It prints using thermal paper, and has an audio output that I put into the laptop mic input. It's not dangerous at all so you shouldn't be afraid. Sticky electrodes can be ha…
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You are incorrect. This circuit can potentially apply unsafe currents across the patient. A standard medical biopotential measurement circuit will have single-point failure protection to prevent conditions like this. This is required by standards like EC11, EC13, and 60601. Those systems are extremely safe. Most hobbyist designs, like the one in this article, do not have such protection. Indeed, for this particular c…
Do you know any hobbyist design that can be built safely?
I'm a bit hopeful it will go on sale in some other country soon that doesn't require a prescription and I can have one shipped to me.
This reminds me of the AliveCor device, which excites and frustrates me. I'm excited because I'm hopeful that when such monitoring becomes dirt cheap and unobtrusive, people might find conditions earlier and have a better chance to treat them. I'm frustrated because in the U.S. it currently requires a prescription from a doctor to buy one. This feels like regulatory nonsense to me. It seems like an obviously low risk…
I have been working with EKG on and off for ten years. I helped with this briefly: http://www.neozap.com/freeECG.htm I would love it if someone could produce a more 'rounded' piece of software. I really love my 12-lead ECG machine I got for £10. It prints using thermal paper, and has an audio output that I put into the laptop mic input. It's not dangerous at all so you shouldn't be afraid. Sticky electrodes can be ha…
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No real danger for EEG if powered from an isolated laptop. ECG can cause safety issues if there is a significant current across the sensor leads, but even that is unlikely unless the completely wrong resister values used and the person hypothetically has a heart condition. Disclaimer: I'm not a physician, neurosurgeon or lawyer. I did however design and repair EEG systems.
You are incorrect. This circuit can potentially apply unsafe currents across the patient. A standard medical biopotential measurement circuit will have single-point failure protection to prevent conditions like this. This is required by standards like EC11, EC13, and 60601. Those systems are extremely safe. Most hobbyist designs, like the one in this article, do not have such protection. Indeed, for this particular c…
Most of the "danger" comes from poor isolation. The skin resistance is too high for EEG to cause major problems. I realize the actual standards have requirements that are detailed and somewhat strict.
The difference is that ECG has sensors that can directly put current through the path to the heart so the risk is higher if there is a worse-case ESD latchup. 5mA is enough to stop a heart in certain conditions.
EEG isn't ECG or EMG and have different characteristics even though they seem vaguely similar.
PS. My contact info is in my profile.