RE: Alpha asymmetry F3 and F4, Ref. to Cz

[Guest guest]

You can get a jumper (from MVAP for example) which will take the input from one electrode at Cz and input it to both reference channels.

Foxx

-----Original Message-----From: Rosemary Herron [mailto:reherron@...] Sent: Thursday, March 04, 2004 6:30 PM Subject: Re: RE: Alpha asymmetry F3 and F4, Ref. to Cz

If electrodes are cupped together over Cz, does the top one really receive the same input? Is there any other way to do this?

[Guest guest]

Where can i find these electrodes, i too worry pasting one electrode on

top of another like beetles mating.

On Mar 5, 2004, at 2:17 AM, foxx wrote:

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[Guest guest]

These jumpers are also very nice if you want to use linked ear

references for assessment or training.

At 1:48 PM -0500 3/5/04, Goldring wrote:

>Where can i find these electrodes, i too worry pasting one electrode on

>top of another like beetles mating.

>

>On Mar 5, 2004, at 2:17 AM, foxx wrote:

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[Guest guest]

Thanks. I'll do some Internet searching for this one.

Rosemary

RE: RE: Alpha asymmetry F3 and F4, Ref. to Cz

You can get a jumper (from MVAP for example) which will take the input from one electrode at Cz and input it to both reference channels.

Foxx

-----Original Message-----From: Rosemary Herron [mailto:reherron@...] Sent: Thursday, March 04, 2004 6:30 PM Subject: Re: RE: Alpha asymmetry F3 and F4, Ref. to Cz

If electrodes are cupped together over Cz, does the top one really receive the same input? Is there any other way to do this?

[Guest guest]

I got mine at mvapmed.com, who seem to have good prices.

Foxx

Re: RE: Alpha asymmetry F3 and F4, Ref. to Cz

Where can i find these electrodes, i too worry pasting one electrode on

top of another like beetles mating.

On Mar 5, 2004, at 2:17 AM, foxx wrote:

<l.gif>

.

.

.

[Guest guest]

BrainMaster has a set for 4 times as much...but they look different. Anyone know the difference?

RE: RE: Alpha asymmetry F3 and F4, Ref. to Cz

I got mine at mvapmed.com, who seem to have good prices.Foxx-----Original Message-----From: Goldring [mailto:paul.goldring@...] Sent: Friday, March 05, 2004 11:49 AM Subject: Re: RE: Alpha asymmetry F3 and F4, Ref. to CzWhere can i find these electrodes, i too worry pasting one electrode on top of another like beetles mating.On Mar 5, 2004, at 2:17 AM, foxx wrote:<l.gif> . . .

[Guest guest]

BrainMaster has a set for 4 times as much...but they look different. Anyone know the difference?

RE: RE: Alpha asymmetry F3 and F4, Ref. to Cz

I got mine at mvapmed.com, who seem to have good prices.Foxx-----Original Message-----From: Goldring [mailto:paul.goldring@...] Sent: Friday, March 05, 2004 11:49 AM Subject: Re: RE: Alpha asymmetry F3 and F4, Ref. to CzWhere can i find these electrodes, i too worry pasting one electrode on top of another like beetles mating.On Mar 5, 2004, at 2:17 AM, foxx wrote:<l.gif> . . .

[Guest guest]

Hi -

You wrote:

What percentages (of Alpha) would you call high, compared to beta/low

beta/etc?

This is hard to answer- it depends on how you measure it. I do not know what raw

voltage ratios should be. Here is how I tell-

First is by visual inspection of the Ec raw waves- alpha should be dominant in

the rear of the head and nice small beta should be dominant in the front. I do

full head EEG's so I can see it in the 19 channel tracings. You can also see it

in brainmaster or bioexplorer raw waves. Frontal alpha becomes more problematic

eyes open and even more problematic when seen during a task condition.

Second is to compare the 19 channel data to a normative database. At

Neurotherapy Dallas we use multiple databases and they pretty much agree on

relative power excess.

Basically, if you can see lots of sinusoidal alpha at Fz in eyes open or task

you definitely have a problem. If you see it Ec, you might have a problem.

[Guest guest]

Rosemary wrote:

" Reference is important- I reported a fairly low correlation between ear and Cz

reference. "

,

I'm having trouble understanding this. Does this mean that assessing for alpha

asymmetry using ear references is lacking in accuracy? Or that using the Cz

reference is lacking in accuracy and therefore is not so useful for training?

If electrodes are cupped together over Cz, does the top one really receive the

same input? Is there any other way to do this?

Are your papers available anywhere online? (or off)

Rosemary H.

The results associated with changing the reference can be confusing-

Different references give different results- this is easily tested by comparing

t3-t4 numbers to T3-a2 and T3-a1 numbers. They will all be somewhat different.

Ear and Cz reference also give different numbers. I checked the correlation

between f3-f4 alpha asymmetry with linked ear and with Cz reference on several

different samples and found between .1 and .3 correlation. It is not at all

uncommon to have left side alpha asymmetry with one reference and right side

with the other. The alpha asymmetry protocol is based on Cz reference.

Different references tell different stories. The differential amps we use to

measure EEG subtract the at data at one site from the data at another. If the

amp samples the data 125 tiles a second, it performs this subtraction for each

sample- channel 1 minus the reference, 125 calculations each second. Cz

reference data looks at the difference between the activity over the vertex and

whatever site you are looking at. It tells how different the EEG at, a site, F3

for example, and Cz. If F3-Cz alpha is very different- you get a big number, if

it is similar, you get a smaller number.

Ear reference F3 data looks at the relationship between the relatively neutral

ear and F3.

Measuring with either reference will be accurate but each reference will give

different results.

I used to live in an old house with a second story window that looked out into a

big oak tree. I loved to sit and look into the middle of the tree. I also liked

to lie underneath the tree and look up into it. I got a very different view of

the tree depending on my point of reference. Cz reference might be the view of

the tree from in the house and ear reference might be the view from the ground.

They are both accurate views and they both let us see the tree differently.

I say- train using whichever reference you assess with.

If you want to train the official alpha asymmetry protocol, you have to use Cz.

I rarely train alpha asymmetry. If someone is depressed, I look at frontal

alpha, if they have lots of round sinusoidal waves in the front, train them

down. And while training them down- make sure left side alpha is lower than

right. Generally, left side alpha is associated with depression, rside with

anxiety and/or ADHD. However, if alpha is high on one side it is almost always

high on the other. I think it is better to get rid it on both sides than try to

shift it from one side to another.

For some very terse abstracts, check the snr site and search on my last name:

www.snr-jnt.org

Re: connecting electrodes one on top of the other- Someone suggested getting a

jumper to let 1 electrode go into 2 sockets- this works great. It is also handy

for coherence or any other 2 channel training- you can use the same reference

for both channels.

[Guest guest]

No, but mine work fine.

-----Original Message-----From: Rosemary Herron [mailto:reherron@...] Sent: Friday, March 05, 2004 7:56 PM Subject: Re: RE: Alpha asymmetry F3 and F4, Ref. to Cz

BrainMaster has a set for 4 times as much...but they look different. Anyone know the difference?

RE: RE: Alpha asymmetry F3 and F4, Ref. to Cz

I got mine at mvapmed.com, who seem to have good prices.Foxx

[Guest guest]

Hi !

Second is to compare the 19 channel data to a normative database. At Neurotherapy Dallas we use multiple databases

and they pretty much agree on relative power excess.

Maps of brain are how picture in kaleidoscope - can deliver of false conclusions .

Pictures, which one we obtain, are very strongly, dependent on from manner of registration raw signal eeg.

, maps, about of which you write: which one electrode reference?

- average, whether other ?

Jan

Studio EEG-Biofeedback

Poland

Re: Alpha asymmetry F3 and F4, Ref. to Cz

Hi -You wrote:What percentages (of Alpha) would you call high, compared to beta/low beta/etc?This is hard to answer- it depends on how you measure it. I do not know what raw voltage ratios should be. Here is how I tell-First is by visual inspection of the Ec raw waves- alpha should be dominant in the rear of the head and nice small beta should be dominant in the front. I do full head EEG's so I can see it in the 19 channel tracings. You can also see it in brainmaster or bioexplorer raw waves. Frontal alpha becomes more problematic eyes open and even more problematic when seen during a task condition.Second is to compare the 19 channel data to a normative database. At Neurotherapy Dallas we use multiple databases and they pretty much agree on relative power excess. Basically, if you can see lots of sinusoidal alpha at Fz in eyes open or task you definitely have a problem. If you see it Ec, you might have a problem.

[Guest guest]

Jan

Our databases all use linked ear reference. The table of numbers are

the important thing- maps are just a pretty way to display the

numbers. We use them to explain the data to the patients.

In addition to the normed data, we also use non-normed weighted

average maps per Limos and Fisch method. This method is very similar

to laplacian but the unit of measure is voltage instead of current

density. One of the most important things we look at is difference

maps based on linked ear reference showing the EEG changes during task

as compared to eyes open baseline.

We also very much rely on inspection of the raw EEG with re-montaging.

As you know, each reference tells a different story and each only

tells part of the story.

Data from assessment is important. You can get assessment data with 2

channels and move the electrodes to multiple sites or you can measure

many sites at the same time. However, the data is not the most

important thing for directing training. Knowledge of how to use the

data is the most important thing.

This group is primarily for people who use the assessment and

treatment method that Pete teaches. It is an excellent method and I

usually hesitate to post here because I use a different though similar

method. However, I have presented several papers on alpha asymmetry

and I was feeling pedantic last night so I did not retrain myself.

Pete posted something important last night about asymmetry- We are

interested in the relative activation of different parts of the brain-

front to back and side to side. Alpha is an indication of reduced

activation, beta is an indication of increased activation. You need to

look at beta asymmetry as well as alpha asymmetry if you want to know

the story about activation.

I hope this comes out ok with your translation program

>

> What percentages (of Alpha) would you call high, compared to beta/low

> beta/etc?

>

> This is hard to answer- it depends on how you measure it. I do not

know what raw voltage ratios should be. Here is how I tell-

>

> First is by visual inspection of the Ec raw waves- alpha should be

dominant in the rear of the head and nice small beta should be

dominant in the front. I do full head EEG's so I can see it in the 19

channel tracings. You can also see it in brainmaster or bioexplorer

raw waves. Frontal alpha becomes more problematic eyes open and even

more problematic when seen during a task condition.

>

> Second is to compare the 19 channel data to a normative database.

At Neurotherapy Dallas we use multiple databases and they pretty much

agree on relative power excess.

>

> Basically, if you can see lots of sinusoidal alpha at Fz in eyes

open or task you definitely have a problem. If you see it Ec, you

might have a problem.

>

>

>

>

[Guest guest]

Thanks .

One more question: If you assessed alpha using 8-12 Hz. do you train down the full range 8-12 Hz. or use a lower setting, i.e., 8-10 Hz ?

(Or say 2-10 Hz. if Delta and Theta are also excessive?)

Rosemary

Re: Alpha asymmetry F3 and F4, Ref. to Cz

Rosemary wrote:"Reference is important- I reported a fairly low correlation between ear and Cz reference.",I'm having trouble understanding this. Does this mean that assessing for alpha asymmetry using ear references is lacking in accuracy? Or that using the Cz reference is lacking in accuracy and therefore is not so useful for training?If electrodes are cupped together over Cz, does the top one really receive the same input? Is there any other way to do this?Are your papers available anywhere online? (or off)Rosemary H.The results associated with changing the reference can be confusing-Different references give different results- this is easily tested by comparing t3-t4 numbers to T3-a2 and T3-a1 numbers. They will all be somewhat different. Ear and Cz reference also give different numbers. I checked the correlation between f3-f4 alpha asymmetry with linked ear and with Cz reference on several different samples and found between .1 and .3 correlation. It is not at all uncommon to have left side alpha asymmetry with one reference and right side with the other. The alpha asymmetry protocol is based on Cz reference.Different references tell different stories. The differential amps we use to measure EEG subtract the at data at one site from the data at another. If the amp samples the data 125 tiles a second, it performs this subtraction for each sample- channel 1 minus the reference, 125 calculations each second. Cz reference data looks at the difference between the activity over the vertex and whatever site you are looking at. It tells how different the EEG at, a site, F3 for example, and Cz. If F3-Cz alpha is very different- you get a big number, if it is similar, you get a smaller number.Ear reference F3 data looks at the relationship between the relatively neutral ear and F3. Measuring with either reference will be accurate but each reference will give different results. I used to live in an old house with a second story window that looked out into a big oak tree. I loved to sit and look into the middle of the tree. I also liked to lie underneath the tree and look up into it. I got a very different view of the tree depending on my point of reference. Cz reference might be the view of the tree from in the house and ear reference might be the view from the ground. They are both accurate views and they both let us see the tree differently. I say- train using whichever reference you assess with.If you want to train the official alpha asymmetry protocol, you have to use Cz. I rarely train alpha asymmetry. If someone is depressed, I look at frontal alpha, if they have lots of round sinusoidal waves in the front, train them down. And while training them down- make sure left side alpha is lower than right. Generally, left side alpha is associated with depression, rside with anxiety and/or ADHD. However, if alpha is high on one side it is almost always high on the other. I think it is better to get rid it on both sides than try to shift it from one side to another.For some very terse abstracts, check the snr site and search on my last name:www.snr-jnt.orgRe: connecting electrodes one on top of the other- Someone suggested getting a jumper to let 1 electrode go into 2 sockets- this works great. It is also handy for coherence or any other 2 channel training- you can use the same reference for both channels.

[Guest guest]

Dear !

Beautifully thank you for answer - I understand You very well.

Translator in direction - ENG-PL works well. Lies in little details.

Grammatical Form is often bad , but text is understood .

Worse in second side: PL-ENG. Here, translations are very humoristic

and strongly ungrammatical. I do not complain!

Most important, that both side can oneself understand.

I understand, EEG registered is with linked ears.

In Poland, often, is Fpz (ELMIKO-Poland, ALIEN-Czech Republic)

Then, done is brainmapping. In this to place is my question:

Maps: absolute power and relative power - done are

- with reference to average electrode

- electrodes of type Common

Which one option you use most often ? Which one firms, you use apparatus eeg ?

Results, which you see, in one's own maps are peaceable with results BrainMaster

For example, both measurements show similar asymmetries frontal alphas ?

Jan

*****************************************

Pięknie dziękuję za odpowiedź -rozumiem Cię bardzo dobrze.

Translator w kierunku -ENG-PL pracuje dobrze.Kłamie w drobnych szczegółach.

Forma gramatyczna jest często zła,ale tekst jest zrozumiały.

Gorzej w drugą stronę: PL-ENG.Tutaj, tłumaczenia są bardzo humorystyczne

i mocno niegramatyczne. Nie narzekam ! Najważniejsze,że obie strony mogą się zrozumieć.

Rozumiem,że badanie eeg, rejestrowane jest z połączonymi uszami.

Następnie, robi się,brainmapping.W tym miejscu jest moje pytanie:

mapy: absolute power i relative power - robione są

- w odniesieniu do średniej elektrody

- elektrody typu Common

Jaką opcję używacie najczęściej ? Jakiej firmy, używasz aparat eeg ?

Czy wyniki,które widzisz, w swoich mapach są zgodne z wynikami BrainMaster.

Przykładowo, oba pomiary wykazują podobną asymetrie czołową alfy ?

Re: Alpha asymmetry F3 and F4, Ref. to Cz

JanOur databases all use linked ear reference. The table of numbers arethe important thing- maps are just a pretty way to display thenumbers. We use them to explain the data to the patients. In addition to the normed data, we also use non-normed weightedaverage maps per Limos and Fisch method. This method is very similarto laplacian but the unit of measure is voltage instead of currentdensity. One of the most important things we look at is differencemaps based on linked ear reference showing the EEG changes during taskas compared to eyes open baseline. We also very much rely on inspection of the raw EEG with re-montaging.As you know, each reference tells a different story and each onlytells part of the story.Data from assessment is important. You can get assessment data with 2channels and move the electrodes to multiple sites or you can measuremany sites at the same time. However, the data is not the mostimportant thing for directing training. Knowledge of how to use thedata is the most important thing. This group is primarily for people who use the assessment andtreatment method that Pete teaches. It is an excellent method and Iusually hesitate to post here because I use a different though similarmethod. However, I have presented several papers on alpha asymmetryand I was feeling pedantic last night so I did not retrain myself.Pete posted something important last night about asymmetry- We areinterested in the relative activation of different parts of the brain-front to back and side to side. Alpha is an indication of reducedactivation, beta is an indication of increased activation. You need tolook at beta asymmetry as well as alpha asymmetry if you want to knowthe story about activation.I hope this comes out ok with your translation program> > What percentages (of Alpha) would you call high, compared to beta/low > beta/etc?> > This is hard to answer- it depends on how you measure it. I do notknow what raw voltage ratios should be. Here is how I tell-> > First is by visual inspection of the Ec raw waves- alpha should bedominant in the rear of the head and nice small beta should bedominant in the front. I do full head EEG's so I can see it in the 19channel tracings. You can also see it in brainmaster or bioexplorerraw waves. Frontal alpha becomes more problematic eyes open and evenmore problematic when seen during a task condition.> > Second is to compare the 19 channel data to a normative database.At Neurotherapy Dallas we use multiple databases and they pretty muchagree on relative power excess. > > Basically, if you can see lots of sinusoidal alpha at Fz in eyesopen or task you definitely have a problem. If you see it Ec, youmight have a problem.> > > >

[Guest guest]

Dear !

Beautifully thank you for answer - I understand You very well.

Translator in direction - ENG-PL works well. Lies in little details.

Grammatical Form is often bad , but text is understood .

Worse in second side: PL-ENG. Here, translations are very humoristic

and strongly ungrammatical. I do not complain!

Most important, that both side can oneself understand.

I understand, EEG registered is with linked ears.

In Poland, often, is Fpz (ELMIKO-Poland, ALIEN-Czech Republic)

Then, done is brainmapping. In this to place is my question:

Maps: absolute power and relative power - done are

- with reference to average electrode

- electrodes of type Common

Which one option you use most often ? Which one firms, you use apparatus eeg ?

Results, which you see, in one's own maps are peaceable with results BrainMaster

For example, both measurements show similar asymmetries frontal alphas ?

Jan

*****************************************

Pięknie dziękuję za odpowiedź -rozumiem Cię bardzo dobrze.

Translator w kierunku -ENG-PL pracuje dobrze.Kłamie w drobnych szczegółach.

Forma gramatyczna jest często zła,ale tekst jest zrozumiały.

Gorzej w drugą stronę: PL-ENG.Tutaj, tłumaczenia są bardzo humorystyczne

i mocno niegramatyczne. Nie narzekam ! Najważniejsze,że obie strony mogą się zrozumieć.

Rozumiem,że badanie eeg, rejestrowane jest z połączonymi uszami.

Następnie, robi się,brainmapping.W tym miejscu jest moje pytanie:

mapy: absolute power i relative power - robione są

- w odniesieniu do średniej elektrody

- elektrody typu Common

Jaką opcję używacie najczęściej ? Jakiej firmy, używasz aparat eeg ?

Czy wyniki,które widzisz, w swoich mapach są zgodne z wynikami BrainMaster.

Przykładowo, oba pomiary wykazują podobną asymetrie czołową alfy ?

Re: Alpha asymmetry F3 and F4, Ref. to Cz

JanOur databases all use linked ear reference. The table of numbers arethe important thing- maps are just a pretty way to display thenumbers. We use them to explain the data to the patients. In addition to the normed data, we also use non-normed weightedaverage maps per Limos and Fisch method. This method is very similarto laplacian but the unit of measure is voltage instead of currentdensity. One of the most important things we look at is differencemaps based on linked ear reference showing the EEG changes during taskas compared to eyes open baseline. We also very much rely on inspection of the raw EEG with re-montaging.As you know, each reference tells a different story and each onlytells part of the story.Data from assessment is important. You can get assessment data with 2channels and move the electrodes to multiple sites or you can measuremany sites at the same time. However, the data is not the mostimportant thing for directing training. Knowledge of how to use thedata is the most important thing. This group is primarily for people who use the assessment andtreatment method that Pete teaches. It is an excellent method and Iusually hesitate to post here because I use a different though similarmethod. However, I have presented several papers on alpha asymmetryand I was feeling pedantic last night so I did not retrain myself.Pete posted something important last night about asymmetry- We areinterested in the relative activation of different parts of the brain-front to back and side to side. Alpha is an indication of reducedactivation, beta is an indication of increased activation. You need tolook at beta asymmetry as well as alpha asymmetry if you want to knowthe story about activation.I hope this comes out ok with your translation program> > What percentages (of Alpha) would you call high, compared to beta/low > beta/etc?> > This is hard to answer- it depends on how you measure it. I do notknow what raw voltage ratios should be. Here is how I tell-> > First is by visual inspection of the Ec raw waves- alpha should bedominant in the rear of the head and nice small beta should bedominant in the front. I do full head EEG's so I can see it in the 19channel tracings. You can also see it in brainmaster or bioexplorerraw waves. Frontal alpha becomes more problematic eyes open and evenmore problematic when seen during a task condition.> > Second is to compare the 19 channel data to a normative database.At Neurotherapy Dallas we use multiple databases and they pretty muchagree on relative power excess. > > Basically, if you can see lots of sinusoidal alpha at Fz in eyesopen or task you definitely have a problem. If you see it Ec, youmight have a problem.> > > >

[Guest guest]

Hi Rosemary

Generally we only train down slow alpha because fast alpha has been associated

with good cognitive processing. The band width depends on the assessment. Our

assessment is not that different from TLC, except we measure the EEG everywhere.

We also have databases so we can compare a person's data to that of an age

matched normal sample.

We do QEEG with single Hz reports in our office so we know the amplitude

distribution at each site and each frequency. We also know how the person's

distribution of alpha, beta, theta, and delta and each individual Hz relative

power compare to average. For example, it is not uncommon to see that 7 and 8 Hz

are higher than average but full band alpha is not.

We make activation maps that show how the EEG changes at each site and at each

frequency when reading a moderately difficult text (we have text at each grade

level so we tailor the task to the individual). These single Hz reports show how

the EEG is distributed so we can see, for example, a focus of slow waves

centered at Fz start at 6 Hz and then get stronger until maximum power is

reached at 8 Hz then tapering off to 10 Hz. We also might see posterior activity

with maximal power at O1 and O2 occurring at 10 Hz in the same person. This is a

common eyes open distribution in adults with depression or anxiety or ADHD. When

we look at reading compared to the eyes open baseline, if the person brain can

read well, we will see the power go down every where. If the person has ADHD,

power generally will go up everywhere, anxiety and depression, the posterior

alpha will block and frontal 6-9 might block too, but maybe not. Dyslexia is a

mixed pattern as there are many different ways a person can have problems.

If we saw lots of frontal slow 6-9 Hz activity in a depressed or anxious person,

we would train it down. We might train beta up there, depending on how much beta

we saw there in the assessment. We decide on a reward frequency based on the

QEEG pattern and on how the person responds to training.

If there is lots of slow activity we will train that too. The training band will

depend upon the assessment and on location. As you know, training slow stuff

frontally can be difficult because of eye movement. You might be able to train

1-10 down at Pz but you might have to train 4-10 or even 5- 10 frontally if eye

movement is a problem.

Date: Sat, 6 Mar 2004 20:17:30 -0500

From: " Rosemary Herron " <reherron@...>

Subject: Re: Alpha asymmetry F3 and F4, Ref. to Cz

Thanks .

One more question: If you assessed alpha using 8-12 Hz. do you train down the

full range 8-12 Hz. or use a lower setting, i.e., 8-10 Hz ?

(Or say 2-10 Hz. if Delta and Theta are also excessive?)

Rosemary

[Guest guest]

,

Do you ever train down excessive fast alpha that's associated with anxiety?

Rosemary

Re: Alpha asymmetry F3 and F4, Ref. to CzThanks .One more question: If you assessed alpha using 8-12 Hz. do you train down the full range 8-12 Hz. or use a lower setting, i.e., 8-10 Hz ? (Or say 2-10 Hz. if Delta and Theta are also excessive?)Rosemary