Guest guest Posted March 13, 2004 Report Share Posted March 13, 2004 , Combining channels is complicated, but here is how I understand it: The left therms will reflect the sum of right and left electrodes and the right therms the difference between the right and left electrodes, so right and left therms do show different amplitudes. (Unlike usually, left therm is not the left electrode, right therm is not the right electrode.) Similarly raw wave form for channel 1 is sum of the two electrodes and raw wave form for channel 2 is the difference between the two. In the feedback control when you set a stop on channel 1 hibeta for example, you are setting an inhibit on the sum of high beta from the right and left electrodes, you are downtraining the sum. If you set a stop on channel 2 hibeta, you are setting an inhibit on the difference in high beta between the right and left electrodes, you are downtraining the difference. But if you are only interested in training the sum, you would set no thresholds on channel 2. The left therms display " - " at the bottom of the therm because you have an inhibit, that is you are downtraining the 2 channel sum of beta and hibeta. The right therms have a " 0 " at the bottom when you have set no feedback for the 2 channel difference. The only way I know to get feedback for results in channel two is to set stops or goes for that channel, in which case therms would not show " 0. " Foxx Combining channels Pete, or anyone; In a previous post the directions for combining channels entialed checking the target boxes for channel one, then leaving the boxes blank for channel 2. Then, one hits the '+' on the task bar. When I do this, say inhibiting beta and hibeta, I get two sets of thermos' (anyone know the plural for thermos? Is it thermi?) with the ones associated with channel one displaying '-' below them, and the ones for channel two displaying '0', indicating niether plus not minus. However, using pitch reward, for channel two you get the pitch feedback when the threshold is crossed going up. I have know idea what is being rewarded in this instance. Pete's previous posy indicated that channel two displays the difference between channel 1 and 2. Why would that be rewarded? Also, because the threshold setting operate in lockstep they end up being the same for the left and the right, which I guess doesn't matter anyway if one doesn't know what one is supposed to be doing with the channel two (or right side) display. The two raw wave forms are labelled channel 1+2, but this doesn't seem right either because the left and right therm(i) seem to be reflecting different amplitudes. Any ideas? SDC Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 13, 2004 Report Share Posted March 13, 2004 , Combining channels is complicated, but here is how I understand it: The left therms will reflect the sum of right and left electrodes and the right therms the difference between the right and left electrodes, so right and left therms do show different amplitudes. (Unlike usually, left therm is not the left electrode, right therm is not the right electrode.) Similarly raw wave form for channel 1 is sum of the two electrodes and raw wave form for channel 2 is the difference between the two. In the feedback control when you set a stop on channel 1 hibeta for example, you are setting an inhibit on the sum of high beta from the right and left electrodes, you are downtraining the sum. If you set a stop on channel 2 hibeta, you are setting an inhibit on the difference in high beta between the right and left electrodes, you are downtraining the difference. But if you are only interested in training the sum, you would set no thresholds on channel 2. The left therms display " - " at the bottom of the therm because you have an inhibit, that is you are downtraining the 2 channel sum of beta and hibeta. The right therms have a " 0 " at the bottom when you have set no feedback for the 2 channel difference. The only way I know to get feedback for results in channel two is to set stops or goes for that channel, in which case therms would not show " 0. " Foxx Combining channels Pete, or anyone; In a previous post the directions for combining channels entialed checking the target boxes for channel one, then leaving the boxes blank for channel 2. Then, one hits the '+' on the task bar. When I do this, say inhibiting beta and hibeta, I get two sets of thermos' (anyone know the plural for thermos? Is it thermi?) with the ones associated with channel one displaying '-' below them, and the ones for channel two displaying '0', indicating niether plus not minus. However, using pitch reward, for channel two you get the pitch feedback when the threshold is crossed going up. I have know idea what is being rewarded in this instance. Pete's previous posy indicated that channel two displays the difference between channel 1 and 2. Why would that be rewarded? Also, because the threshold setting operate in lockstep they end up being the same for the left and the right, which I guess doesn't matter anyway if one doesn't know what one is supposed to be doing with the channel two (or right side) display. The two raw wave forms are labelled channel 1+2, but this doesn't seem right either because the left and right therm(i) seem to be reflecting different amplitudes. Any ideas? SDC Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 15, 2004 Report Share Posted March 15, 2004 Fox; Thanks for your response. I have a couple of follow-up questions, just for clarification. [ " But if you are only interested in training the sum, you would set no thresholds on channel 2 " ]. By 'set no thresholds', do you mean raise them so high that they are never crossed? (Thresholds are set automatically to begin with, and one gets feedback when set to 'ignore' by default, when the threshold is crossed going up). [ " The only way I know to get feedback for results in channel two is to set > stops or goes for that channel, in which case therms would not show " 0. " ] Again, I get feedback for Channel 2 regardless of whether I set 'stop' 'go', or 'ignore' in Ch 2. Feedback for ch 1 comes into the left ear (using headphones of course) and for channel 2 through the right. I could, again, just raise the thresholds in ch 2 so high that they would never be crossed. What do other people do?, assuming that people aren't actually using the second channel to train differences. SDC > , > > Combining channels is complicated, but here is how I understand it: > > The left therms will reflect the sum of right and left electrodes and > the right therms the difference between the right and left electrodes, > so right and left therms do show different amplitudes. (Unlike usually, > left therm is not the left electrode, right therm is not the right > electrode.) > > Similarly raw wave form for channel 1 is sum of the two electrodes and > raw wave form for channel 2 is the difference between the two. > > In the feedback control when you set a stop on channel 1 hibeta for > example, you are setting an inhibit on the sum of high beta from the > right and left electrodes, you are downtraining the sum. > > If you set a stop on channel 2 hibeta, you are setting an inhibit on the > difference in high beta between the right and left electrodes, you are > downtraining the difference. But if you are only interested in training > the sum, you would set no thresholds on channel 2. > > The left therms display " - " at the bottom of the therm because you have > an inhibit, that is you are downtraining the 2 channel sum of beta and > hibeta. The right therms have a " 0 " at the bottom when you have set no > feedback for the 2 channel difference. > > The only way I know to get feedback for results in channel two is to set > stops or goes for that channel, in which case therms would not show " 0. " > > Foxx > > Combining channels > > > Pete, or anyone; > > In a previous post the directions for combining channels entialed > checking the target boxes for channel one, then leaving the boxes > blank for channel 2. Then, one hits the '+' on the task bar. > > When I do this, say inhibiting beta and hibeta, I get two sets of > thermos' (anyone know the plural for thermos? Is it thermi?) with the > ones associated with channel one displaying '-' below them, and the > ones for channel two displaying '0', indicating niether plus not > minus. However, using pitch reward, for channel two you get the > pitch feedback when the threshold is crossed going up. I have know > idea what is being rewarded in this instance. Pete's previous posy > indicated that channel two displays the difference between channel 1 > and 2. Why would that be rewarded? Also, because the threshold > setting operate in lockstep they end up being the same for the left > and the right, which I guess doesn't matter anyway if one doesn't > know what one is supposed to be doing with the channel two (or right > side) display. The two raw wave forms are labelled channel 1+2, but > this doesn't seem right either because the left and right therm(i) > seem to be reflecting different amplitudes. Any ideas? > > SDC > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 15, 2004 Report Share Posted March 15, 2004 Fox; Thanks for your response. I have a couple of follow-up questions, just for clarification. [ " But if you are only interested in training the sum, you would set no thresholds on channel 2 " ]. By 'set no thresholds', do you mean raise them so high that they are never crossed? (Thresholds are set automatically to begin with, and one gets feedback when set to 'ignore' by default, when the threshold is crossed going up). [ " The only way I know to get feedback for results in channel two is to set > stops or goes for that channel, in which case therms would not show " 0. " ] Again, I get feedback for Channel 2 regardless of whether I set 'stop' 'go', or 'ignore' in Ch 2. Feedback for ch 1 comes into the left ear (using headphones of course) and for channel 2 through the right. I could, again, just raise the thresholds in ch 2 so high that they would never be crossed. What do other people do?, assuming that people aren't actually using the second channel to train differences. SDC > , > > Combining channels is complicated, but here is how I understand it: > > The left therms will reflect the sum of right and left electrodes and > the right therms the difference between the right and left electrodes, > so right and left therms do show different amplitudes. (Unlike usually, > left therm is not the left electrode, right therm is not the right > electrode.) > > Similarly raw wave form for channel 1 is sum of the two electrodes and > raw wave form for channel 2 is the difference between the two. > > In the feedback control when you set a stop on channel 1 hibeta for > example, you are setting an inhibit on the sum of high beta from the > right and left electrodes, you are downtraining the sum. > > If you set a stop on channel 2 hibeta, you are setting an inhibit on the > difference in high beta between the right and left electrodes, you are > downtraining the difference. But if you are only interested in training > the sum, you would set no thresholds on channel 2. > > The left therms display " - " at the bottom of the therm because you have > an inhibit, that is you are downtraining the 2 channel sum of beta and > hibeta. The right therms have a " 0 " at the bottom when you have set no > feedback for the 2 channel difference. > > The only way I know to get feedback for results in channel two is to set > stops or goes for that channel, in which case therms would not show " 0. " > > Foxx > > Combining channels > > > Pete, or anyone; > > In a previous post the directions for combining channels entialed > checking the target boxes for channel one, then leaving the boxes > blank for channel 2. Then, one hits the '+' on the task bar. > > When I do this, say inhibiting beta and hibeta, I get two sets of > thermos' (anyone know the plural for thermos? Is it thermi?) with the > ones associated with channel one displaying '-' below them, and the > ones for channel two displaying '0', indicating niether plus not > minus. However, using pitch reward, for channel two you get the > pitch feedback when the threshold is crossed going up. I have know > idea what is being rewarded in this instance. Pete's previous posy > indicated that channel two displays the difference between channel 1 > and 2. Why would that be rewarded? Also, because the threshold > setting operate in lockstep they end up being the same for the left > and the right, which I guess doesn't matter anyway if one doesn't > know what one is supposed to be doing with the channel two (or right > side) display. The two raw wave forms are labelled channel 1+2, but > this doesn't seem right either because the left and right therm(i) > seem to be reflecting different amplitudes. Any ideas? > > SDC > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 15, 2004 Report Share Posted March 15, 2004 I guess I am. I always pick the the predifined protocal that is closest to what I want, then alter it to suite my purposes. But when I said 'set automatically' I only meant that there are thresholds (the actual black horizontal line that dissects the therms) displayed on both the left set of therms and the right. I know of the various ways of setting them where you want them. I just wondered why anyone would use them to train the differences between the two sites. > > , > > > > Combining channels is complicated, but here is how I understand it: > > > > The left therms will reflect the sum of right and left electrodes > and > > the right therms the difference between the right and left > electrodes, > > so right and left therms do show different amplitudes. (Unlike > usually, > > left therm is not the left electrode, right therm is not the right > > electrode.) > > > > Similarly raw wave form for channel 1 is sum of the two electrodes > and > > raw wave form for channel 2 is the difference between the two. > > > > In the feedback control when you set a stop on channel 1 hibeta for > > example, you are setting an inhibit on the sum of high beta from the > > right and left electrodes, you are downtraining the sum. > > > > If you set a stop on channel 2 hibeta, you are setting an inhibit > on the > > difference in high beta between the right and left electrodes, you > are > > downtraining the difference. But if you are only interested in > training > > the sum, you would set no thresholds on channel 2. > > > > The left therms display " - " at the bottom of the therm because you > have > > an inhibit, that is you are downtraining the 2 channel sum of beta > and > > hibeta. The right therms have a " 0 " at the bottom when you have set > no > > feedback for the 2 channel difference. > > > > The only way I know to get feedback for results in channel two is > to set > > stops or goes for that channel, in which case therms would not > show " 0. " > > > > Foxx > > > > Combining channels > > > > > > Pete, or anyone; > > > > In a previous post the directions for combining channels > entialed > > checking the target boxes for channel one, then leaving the boxes > > blank for channel 2. Then, one hits the '+' on the task bar. > > > > When I do this, say inhibiting beta and hibeta, I get two sets > of > > thermos' (anyone know the plural for thermos? Is it thermi?) with > the > > ones associated with channel one displaying '-' below them, and the > > ones for channel two displaying '0', indicating niether plus not > > minus. However, using pitch reward, for channel two you get the > > pitch feedback when the threshold is crossed going up. I have know > > idea what is being rewarded in this instance. Pete's previous posy > > indicated that channel two displays the difference between channel > 1 > > and 2. Why would that be rewarded? Also, because the threshold > > setting operate in lockstep they end up being the same for the left > > and the right, which I guess doesn't matter anyway if one doesn't > > know what one is supposed to be doing with the channel two (or > right > > side) display. The two raw wave forms are labelled channel 1+2, > but > > this doesn't seem right either because the left and right therm(i) > > seem to be reflecting different amplitudes. Any ideas? > > > > SDC > > > > > > > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 16, 2004 Report Share Posted March 16, 2004 Ah! Here is the confusion. When I combine channels I continue to get sound feedback on channel 2 even though the bands are set to 'ignore' and there are '0's below the therms. Maybe this is a software glitch? > > > , > > > > > > Combining channels is complicated, but here is how I understand > it: > > > > > > The left therms will reflect the sum of right and left electrodes > > and > > > the right therms the difference between the right and left > > electrodes, > > > so right and left therms do show different amplitudes. (Unlike > > usually, > > > left therm is not the left electrode, right therm is not the right > > > electrode.) > > > > > > Similarly raw wave form for channel 1 is sum of the two electrodes > > and > > > raw wave form for channel 2 is the difference between the two. > > > > > > In the feedback control when you set a stop on channel 1 hibeta > for > > > example, you are setting an inhibit on the sum of high beta from > the > > > right and left electrodes, you are downtraining the sum. > > > > > > If you set a stop on channel 2 hibeta, you are setting an inhibit > > on the > > > difference in high beta between the right and left electrodes, you > > are > > > downtraining the difference. But if you are only interested in > > training > > > the sum, you would set no thresholds on channel 2. > > > > > > The left therms display " - " at the bottom of the therm because you > > have > > > an inhibit, that is you are downtraining the 2 channel sum of beta > > and > > > hibeta. The right therms have a " 0 " at the bottom when you have > set > > no > > > feedback for the 2 channel difference. > > > > > > The only way I know to get feedback for results in channel two is > > to set > > > stops or goes for that channel, in which case therms would not > > show " 0. " > > > > > > Foxx > > > > > > Combining channels > > > > > > > > > Pete, or anyone; > > > > > > In a previous post the directions for combining channels > > entialed > > > checking the target boxes for channel one, then leaving the boxes > > > blank for channel 2. Then, one hits the '+' on the task bar. > > > > > > When I do this, say inhibiting beta and hibeta, I get two sets > > of > > > thermos' (anyone know the plural for thermos? Is it thermi?) with > > the > > > ones associated with channel one displaying '-' below them, and > the > > > ones for channel two displaying '0', indicating niether plus not > > > minus. However, using pitch reward, for channel two you get the > > > pitch feedback when the threshold is crossed going up. I have > know > > > idea what is being rewarded in this instance. Pete's previous > posy > > > indicated that channel two displays the difference between > channel > > 1 > > > and 2. Why would that be rewarded? Also, because the threshold > > > setting operate in lockstep they end up being the same for the > left > > > and the right, which I guess doesn't matter anyway if one doesn't > > > know what one is supposed to be doing with the channel two (or > > right > > > side) display. The two raw wave forms are labelled channel 1+2, > > but > > > this doesn't seem right either because the left and right therm (i) > > > seem to be reflecting different amplitudes. Any ideas? > > > > > > SDC > > > > > > > > > > > > > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 17, 2004 Report Share Posted March 17, 2004 I can watch the screen and see that the sound coming in the right ear is reflecting the therm activity from the right therms. -- In , " foxx " <foxx@p...> wrote: > Ah. With my laptop's crummy sound system I can't get a pure separation > of sounds to the two ears, so perhaps Tom Collura could help best. I > think I recall tho that two different feedback conditions even if there > are in the same EEG channel can give you different sounds to each ear. > So I wonder if what you are hearing in the right ear is actually from > channel 2. Does it still seem to happen without the headphones? > > Foxx > > Re: Combining channels > > > Ah! Here is the confusion. When I combine channels I continue to get > sound feedback on channel 2 even though the bands are set to 'ignore' > and there are '0's below the therms. Maybe this is a software glitch? > > > > > > If for example, in channel two, for alpha, you have a threshold > value of > > 8.0 (maybe it got there from an earlier version of the protocol) > but you > > have checked ignore, then on the screen while you are running, the > line > > will appear on the alpha therm but there will be a zero at the > bottom of > > the therm. In this case the feedback is not operating even tho the > line > > is there. Perhaps that might be helpful to see what's going on. > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 17, 2004 Report Share Posted March 17, 2004 Tom; I started this thread with a question about combining channels, and I believe I understand it now. I quwestioned why, when comining channels, if the right therms reflected the difference between ch1 and ch2, would you get audio feedback from the right-side therms (why would one want to hear feedback for the difference. What I am understanding now is that this isn't intentional, and one should just set the thresholds high on the right, so that they don't sound. Then you are left with feedback reflecting the combination of 1 and 2, which you will only hear in your left ear. SDC Foxx answered it. > > > If for example, in channel two, for alpha, you have a threshold > > value of > > > 8.0 (maybe it got there from an earlier version of the protocol) > > but you > > > have checked ignore, then on the screen while you are running, the > > line > > > will appear on the alpha therm but there will be a zero at the > > bottom of > > > the therm. In this case the feedback is not operating even tho the > > line > > > is there. Perhaps that might be helpful to see what's going on. > > > > > > > > > > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 17, 2004 Report Share Posted March 17, 2004 I get it. This answers a question I was about to ask, i.e., what suggestions folks might have for lowering beta and beta coherence at P3/P4. This also might account for some negative effects I experienced downtraining beta there using the sum channel mode. Thanks Tom. > > > > > If for example, in channel two, for alpha, you have a threshold > > > > value of > > > > > 8.0 (maybe it got there from an earlier version of the protocol) > > > > but you > > > > > have checked ignore, then on the screen while you are running, > > the > > > > line > > > > > will appear on the alpha therm but there will be a zero at the > > > > bottom of > > > > > the therm. In this case the feedback is not operating even tho > > the > > > > line > > > > > is there. Perhaps that might be helpful to see what's going on. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Quote Link to comment Share on other sites More sharing options...
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