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Temporal Brain Score
atanguay
Posted on 09/15/21 16:54:47
Number of posts: 9
atanguay posts:

Hi,

Do you recommend mean centering values when displaying the temporal brain scores in a manuscript? Or is it fine to use the exported temporal brain scores, which are also those shown when using the PLS gui?

I have also seen % change displayed. Is that a better option or up to personal preference?

Also for anyone browsing through the message board to find tips on temporal brain scores: It took me time to figure out how to get means from the bs_data (to also get the SE). First, these values were exported using the PLS Gui from the window used to view the temporal brain scores. If I'm correct, in this case the St_Evt_list tells us how the data is structured (e.g., in my case, rows were cond 1, 2, 3, 4 repeated * n participants from top to bottom and lag is shown as separate columns).

Thank you for input about this.


Annick

 

 

Replies:

Untitled Post
rmcintosh
Posted on 09/16/21 16:38:52
Number of posts: 385
rmcintosh replies:

HI Annick

It is okay to use mean-centreing for the temporal brain scores. It will emphasize the difffernece that drives the PLS analysis. And I think you're correct on the structure of the scores but let me try to rephrase - the scores should be ordered as subject withiin condition.

cheers

Randy



Untitled Post
atanguay
Posted on 09/17/21 10:50:28
Number of posts: 9
atanguay replies:

Hi Randy,

Excellent.

I'll confirm though that I understand the set-up for the data correctly. 

What you describe is like this (I think) for two conditions and 4 participants:

Cond 1 ID 1
Cond 1 ID 2
Cond 1 ID 3
Cond 1 ID 4
Cond 2 ID 1
Cond 2 ID 2
Cond 2 ID 3
Cond 2 ID 4

 

And that's how I remember the set-up for other PLS data.

 

But for the temporal brain scores, the only way I can replicate what I see in the gui and in the mean_bs, is to go with this set-up

 

Cond 1 ID 1
Cond 2 ID 1
Cond 1 ID 2
Cond 2 ID 2
Cond 1 ID 3
Cond 2 ID 3
Cond 1 ID 4
Cond 2 ID 4

 

I thought of this because of this part in the code, but I don't know Matlab language, so I have no clue what it is doing. I just assumed it took info from st_evt_list, and that list has the list of conditions (1, 2... repeatedly until all participants were covered I'm guessing).

 for i = 1:c1

      bs_data_mean(i,:) = mean(bs_data(find(st_evt_list==i),:),1);

   end

 

Thank you for any feedback on this and all the help you have previously given.

 

Annick

 



Untitled Post
rmcintosh
Posted on 09/18/21 09:17:12
Number of posts: 385
rmcintosh replies:

quote:

Hi Randy,

Excellent.

I'll confirm though that I understand the set-up for the data correctly. 

What you describe is like this (I think) for two conditions and 4 participants:

Cond 1 ID 1
Cond 1 ID 2
Cond 1 ID 3
Cond 1 ID 4
Cond 2 ID 1
Cond 2 ID 2
Cond 2 ID 3
Cond 2 ID 4

 

And that's how I remember the set-up for other PLS data.

 

But for the temporal brain scores, the only way I can replicate what I see in the gui and in the mean_bs, is to go with this set-up

 

Cond 1 ID 1
Cond 2 ID 1
Cond 1 ID 2
Cond 2 ID 2
Cond 1 ID 3
Cond 2 ID 3
Cond 1 ID 4
Cond 2 ID 4

 

I thought of this because of this part in the code, but I don't know Matlab language, so I have no clue what it is doing. I just assumed it took info from st_evt_list, and that list has the list of conditions (1, 2... repeatedly until all participants were covered I'm guessing).

 for i = 1:c1

      bs_data_mean(i,:) = mean(bs_data(find(st_evt_list==i),:),1);

   end

 

Thank you for any feedback on this and all the help you have previously given.

 

Annick

 

You're correct, Annick.  I had to go way back to see but in the whatsnew.txt file I found this:

Version 4.0603062  March 6, 2006
1. Modified "Export Data" for fMRI "Response Function Plot"
and "Temporal Brain Scores Plot". The "st_evt_list" in
the exported file is always sorted as condition-within-
subjects, so as the "data" variable.



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