Thread: Published in Nature Neuroscience: 77% induction rate with electrodes on the scalp at 40 Hertz

Its look like your TENS use byphasic asimetric rectangular waveform not sinus with max pulse duration of 300us (0,3ms) you set 200us (0,2ms pulse size) and 40Hz .
In 40Hz signal one cycle last 25ms and one phase of it 12,5ms your stimulation last only about 16%(200 from 1250us) of phase and its rectangular pulse.
Your stimulation is very different but still can have some effect its need test with EEG to look to brain synchronization.

Electrodes i assume you use 25cm2 electrodes your current density will be 40uA/cm2 its 2x more than in the study from my staint point is better .If you plan use 4 alectrodes like in study use bouth channels of TENS device.

Also setup with 1mA steps dont allow more precise setup for comfort or other aplication , elctrode size .
TENS device also not have optipn of ramping my signal use 30s ram in and in and 30s ram down this reduce skin fealing and is not "taht large schock for brainwaves (ramping is from -30db in audio signal)
PcSpeaker vesrion is very simple and is safe anought if know waht you doing main advanatage is i can easily test various types of signal by simply change audio file and i can also try pulsed DC stimulation (add diode to one output wire) or try very complex waves even stimulation with recorded EEG signal form LD

Originally Posted by ATA

Its look like your TENS use byphasic asimetric rectangular waveform not sinus with max pulse duration of 300us (0,3ms) you set 200us (0,2ms pulse size) and 40Hz .
In 40Hz signal one cycle last 25ms and one phase of it 12,5ms your stimulation last only about 16%(200 from 1250us) of phase and its rectangular pulse.
Your stimulation is very different but still can have some effect its need test with EEG to look to brain synchronization.

Thank you for that!
So, it is better to set the pulse duration to 300us (max) - I think this is what jeff used as well, and this is what I will do!
Testing starts tonight!

Im not sure how TENS controll current in page they write mA values and note about 500Ohms load so maybe there is no "online" current control .If it true the mA values on device and actual current trought brain can be VERY different . Probabably much lower .

Can you measurue it ?

Hi guys.
Just registered to DV, I'm the one who kinda brought ATA here by contacting him on FB and showing him this thread.
My electronics memories are far away now (I had been studying electronics for 8 years but I stoped studies and practice 20 years ago (after Engeneer school)), but I'm very interested about next generation LD devices, like Aurora or electic stimulation based LD devices.
Thank you, guys, for your work, I will read your conversations about luciding, and home made devices as I plan to buy one or to make my own device.
Up to now, I'm still fighting with my 5 year old Rem-Dreamer to have LD (sometimes it work, sometimes not as you guess).
as ATA noticed it on the Luciding FB, someone did some good research about electro stimulation for LD 5 years ago.
Did you guys take a look to this: ?

Edit:
(I am not allowed to post links for now, I suggest you to do a google research "Method and apparatus for electrically generating signal for inducing lucid dreaming"

Originally Posted by ATA

... the mA values on device and actual current trought brain can be VERY different . Probabably much lower .
Can you measurue it ?

The booklet says that the intensity is adjustable from 0-80mA at 500Ohms.
It is adjustable with a knob, so there are no steps - you can set any value and there is no live reading. So, I could not set the device to 2mA as Jeff suggested.
I do have a multimeter however and did some live readings: the actual current is much lower...
I begin to feel the stimulation at 0,5μA (0,0005 mA) and it gets really uncomfortable at 6μA (0,006mA). So, setting the device at 2mA is unrealistic, the actual current is much lower....

How to do you mesure it 0,5uA is definitly wrong .

Originally Posted by ATA

How to do you mesure it 0,5uA is definitly wrong .

Agreed, i'm not expert at that kind of stuff yet i'm sure that if it would get really bad at 6μA then actual TENS Devices would be absolute painfest rather than pain relief

Try to describe how do you measure it .

Measuring TENS currnet may be problematic and also is the problem with peak current and effective current . I assume mutimetter mesure effective current (please someone with better knowledge of electronic to veryfi information in this post).

For sinus wave is effective current 1,44x lower than peak current.
So for my 0,6mA stimulation (effective current) will peak current(current when sine wave is on peak) 0,864mA

For TENS with your setup (200us pulse ,40hz) will be effective current only 16% of peak current . So of you setup 1mA on device and we assume they mean effective current the max current will be 6,25mA

This still dindt explain your measurment values is very important how do you prepare your skin and what eletrodes are use. Important is current density. 1mA of stimulation from 25cm2 lectrode will have current desity 40uA/cm2 and will be ok but if you use neadle like electrode or wire the current density be far more than 1mA/cm2 and cause pain like hell nad probably also skin burns .

Originally Posted by ATA

Try to describe how do you measure it .

My setup was this: I connected the TENS Device to my forehead with square, classic gel electrodes. I connected the multimeter in series in one of the wires and set it to alternating current-Ampere measurement.
I was also surprised by my measurement, but think that it is correct.
I also have a conventional amperometer - with needle - that measures 0-10mA. When connecting this in series, the measurement was zero even at the most painful setting I could try...

TEST of TENS setup

Test on fingers (thumb - index ) surface about 2cm2 waveform biphasic retangular 200ms pulse 40hz

2cm2 0,12 mA no fealing
2cm2 0,20 mA muscle pulsation

so i get to 60uA/cm2 and no fealing
and to 100uA/cm2 without problem
*voltage only 3V with load

TEST on head F3-F4 , electrodes 4cm2
0,25mA ok
0,55mA ok but slight phosphenes , no skin fealing

62 uA/cm2
137 uA/cm2

If it mesure effective value of current peak current will be 6,25x higher !!!
I mesure it on old analog metter on 0,3mA scale limit it work OK also on 0,6mA scale on 3mA i dont get any response.

I get 137uA/current density without problem but you measured problemes with current denity 0,02uA/cm2 is 6850x lower than my value .
Possible explanation of different measurmet is your electrodes is very dirty and have non even contact with skin , also TENS can have volatage about 100V in my test was 3V ,another possible cause is multimetter have problems measure this type of very weak signal with this waveform

*if you make new thread please move post there

------------------------------------------------------------------------

1:20AM
TEST head F3-F4 (40hz 5min with 30s ramp up/down) 4cm2

Max tested current 0,6mA no fealing but visible pohosphnes
Current during test 0,25mA and very slight phosphenes noticable only sometimes
Current go Up in stimulation about 0,1mA i manualy change volume to get stable 0,25mA

Current density 62uA/cm2
I pick for first test frontal stimulation becouse there is larger risk of phosphnes induction.

Subjective fealings: during stimulation normal , after stimultion little bit incerased wakfullnes and elevated endorphines (slight smile)

Info from Subconscious (puerly subjective) :
Intestity of stimulation: stimulation current to strong cuase forced tunning dont allow natural rythm changes , recommended about 38uA/cm2
Stimulation time: too long for this current level , optimal at this currnet level 20s
Electrode position: recommended insted of F4 something like FT8 in foront of ear
Frequency : recommended 37,16Hz
Waveform : no data

TEST2 same only current changed to recommended 0,15mA
small current fluctuation during stimulation 0,13-0,15mA
Current density 37,5uA/cm2

Subjective fealings: during stimulation normal , after only very slight change in wakefullnes+ (time to go sleep is 1:15AM here )

Info from Subconscious (puerly subjective) :
Intestity of stimulation: OK
Stimulation time: OK can be up to 20min
Electrode position: recommended insted of F4 something like FT8 in foront of ear
Frequency : recommended 37,167Hz
Waveform : no data

I try if electrodes stay at head after night and be usable (stable contact)

UPDATE 7:09 AM
There have been stimulatory effects my wakefulness gradually increased and i can sleep for hours.
I noticed start of increase wakefulness about 25min post stim.
So far I've slept an estimated less than 2 hours .I feel veryawake definitely much better for me than normal afterawake state or awake in middle of night.

I remeber few fragmnets of about 3 short dreams. One of them have short perod of lucidity.LD was spontaneous lucidity in dream but last only about 20s I do not remember very well how it ended nad my memory from dreams is also very fragmnetet (i not train dream memory for many months) .From this very limited data it seams that frontal stimulation have no effect on memory or only wery weak but have strang effect on increase wakefullnes.

Over the last month I had about 2 LD and not do any Ld techniqe to limit interaction with stimulation .2 month back i have about 1LD per week.

Info from Subconscious (puerly subjective) :
Chance for LD befor stimulation : 10,6%
Chance for LD after stimulation : 67 %

It is still too early to say that the stimulation can cause LD it will take more attempts in the future to peove it. It need also sham stimulation to exclude the placebo effect, measurement of EEG, EOG verfied LD ..
But this first result seems very good.

The electrodes seem to be OK after 6 hours on the head ,contact with whole surface ,tehyt do not move ..

Originally Posted by ATA

UPDATE
There have been stimulatory effects my wakefulness gradually increased and i can sleep for hours.
I noticed start of increase wakefulness about 25min post stim.
So far I've slept an estimated less than 2 hours .I feel veryawake definitely much better for me than normal afterawake state or awake in middle of night.

I remeber few fragmnets of about 3 short dreams. One of them have short perod of lucidity.LD was spontaneous lucidity in dream but last only about 20s I do not remember very well how it ended nad my memory from dreams is also very fragmnetet (i not train dream memory for many months) .From this very limited data it seams that frontal stimulation have no effect on memory or only wery weak but have strang effect on increase wakefullnes.

Over the last month I had about 2 LD and not do any Ld techniqe to limit interaction with stimulation .2 month back i have about 1LD per week.

Info from Subconscious (puerly subjective) :
Chance for LD befor stimulation : 10,6%
Chance for LD after stimulation : 67 %

It is still too early to say that the stimulation can cause LD it will take more attempts in the future to peove it. It need also sham stimulation to exclude the placebo effect, measurement of EEG, EOG verfied LD ..
But this first result seems very good.

The electrodes seem to be OK after 6 hours on the head ,contact with whole surface ,tehyt do not move ..

For lucidity you should try stimulation along with WBTB perhaps?
So, wake up after few hours of sleep like 6, turn on stimulation or put delay of 15 min on it, go back to sleep, see results?

The initial plan was to use stimulation after 6h of sleep where I use playlist witch recordings 20 minutes of silence and 5min of stimulation played in loop . But i dount expecting so strong effects after a stimulation test.
I leave WBTB test to next try.Probably use the same electrode montage F3-F4 is not best for effect but easiest to prepare.Other montages needs more preparation i have now beard so i must shave or use more conductive gel.If F3-F4 work is be simplest for use TENS type of electrodes .

@SearcherTMR

If however they send them, it will be interesting to see if they actually do anything - from a video they posted, it seems their electrodes are metallic buttons!

These arent just normal metallic buttons but stainless steel non-contact Sensors like Neurosky uses:

http://i00.i.aliimg.com/wsphoto/v0/1...teel-round.jpg

From my stant point neurosky is toy not EEG and use stainless steel is far from ideal.I use gold electrodes with silver wire and to get hi-quality signal is also needet some skin preparation right amount of conductive gel..
But this all depend how quality of signal we want to get for EOG mesurment is seems OK use this buttons. Im worried about stimulation by them we still dount have any infomation about stimulation current, current desity , lenght of stimulation and many other paramteres luciding planed to use.

@ATA

By the way: very impressive. Im looking forward for the next test.

Edit: Yes, Neurosky itself is a toy because it doesnt send any raw data. But Luciding only use their Neurosky EEG-Asic board which is useable. Here another pic of the Neurosky electrodes. They look exactly like the Luciding ones:

http://ecx.images-amazon.com/images/...L._SL1151_.jpg

If luciding use this as stimulation electrode i assume diametter of button 1cm it give 0,785cm2 of surface area

Current desities at various imput current (if device use only only 2 electrodes for stimulation)
1mA 1273uA/cm2
0,5mA 636uA/cm2
0,25mA 318uA/cm2

Stimulation current density in study was 20uA/cm2 if luciding use this current desity its output current is only 15,7uA (0,0157mA)

From my test i found that usable current desity is max about 120uA/cm2 and ideal about 40uA/cm2 so if luciding use same range its ouput current be in range 30-95uA (0,03-0,095mA)
I use prepated skin 70% isopropyl alcohol and EEG conductiv gel metal buttons without gela nd praparation can causeadverese fealing in much lower currents.
*current form smaller electrode man same current density is in brain lower doe to various effect but skin fealing is realively the same.

Luciding does use 4 electrodes. Also i would guess that they have a diameter of 2 cm2 :

https://fbcdn-sphotos-h-a.akamaihd.n...c386af71c0e337

So they could have a current of 60uA?

I see 5 electrods wich is weird.

Edit: I used "weird" but as English is not my every day language, it is maybe too strong.
By weird I just mean It is strange, I wonder why there is 5 Electrodes, and not 4 or 6

Originally Posted by Kaan

I see 5 electrods wich is weird.

How so?

You're right, sorry. But why it's weird?

sorry for my neebie question but In the pic we can see 2 head bands, and each one seams to have 5 electrodes on it.
Aren't electrodes supposed to go 2 by 2 ?
to which one the 5th is supposed to be connected?

Edit: By connected I don't mean connected, but linked as the curent goes from one to the other one through the skin

Hard to say now it possible that 3 electrodes are for EOG measurment (+,-,GND) and two are ment for stimulation .
*for me is thers electrode setup also very wierd

Originally Posted by ATA

Hard to say now it possible that 3 electrodes are for EOG measurment (+,-,GND) and two are ment for stimulation .
*for me is thers electrode setup also very wierd

I don't think we should trust that image as an actual placement of their electrodes.
It seems to be more like picture featuring not assembled parts of device...


Their electrode position perhaps might be similar to the one they used on prototype version of device:

Electrode placement in this pictures is just chaos.

Headband of this wide cant get to measure EOG in supraorbital position above eye and a stimulate F3 (DLPFC) in same time .