GLMsingle for fast desing

[alireza-kr]

Hello

I have a visual category localizer designed for block-design analysis. However, I need to extract responses for individual trials within each block. The challenge is that the inter-stimulus interval (ISI) is very short (300 ms).

Here is the design: stimuli were presented in 6-second blocks (mean inter-block interval = 6 seconds, jittered to 4, 6, or 8 seconds). Within each block, stimuli were flashed for 200 ms, with a 300 ms ISI.

I came across [1], which mentions that GLMsingle can help decorrelate response estimates between trials that are temporally close. Would GLMsingle be suitable for my case, given the short ISI?

[1] Prince, J. S., Charest, I., Kurzawski, J. W., Pyles, J. A., Tarr, M. J., & Kay, K. N. (2022). Improving the accuracy of single-trial fMRI response estimates using GLMsingle. eLife, 11. https://doi.org/10.7554/elife.77599

[kendrickkay]

So, it sounds like often the next trial of interest starts as soon as 500 ms after the current one. This is indeed very challenging from a decorrelation point of view. That being said, it might "work", in the sense that it's really just a quantitative issue. (The question is, how well does it work?) Certainly it will help your case if you have multiple and (pseudorandom) repeats of your individual trials that occur across trials/runs/etc. So, I'd have to see your design matrix (and the number of runs) you have in order to have a better guess whether it's going to work well or not.

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On Jan 5, 2025, at 2:06 PM, Alireza Karami ***@***.***> wrote: Hello I have a visual category localizer designed for block-design analysis. However, I need to extract responses for individual trials within each block. The challenge is that the inter-stimulus interval (ISI) is very short (300 ms). Here is the design: stimuli were presented in 6-second blocks (mean inter-block interval = 6 seconds, jittered to 4, 6, or 8 seconds). Within each block, stimuli were flashed for 200 ms, with a 300 ms ISI. I came across [1], which mentions that GLMsingle can help decorrelate response estimates between trials that are temporally close. Would GLMsingle be suitable for my case, given the short ISI? [1] Prince, J. S., Charest, I., Kurzawski, J. W., Pyles, J. A., Tarr, M. J., & Kay, K. N. (2022). Improving the accuracy of single-trial fMRI response estimates using GLMsingle. eLife, 11. https://doi.org/10.7554/elife.77599 — Reply to this email directly, view it on GitHub <#164>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAU2DEXVTPAA6BN27DL3MHT2JGGGBAVCNFSM6AAAAABUUNSSZWVHI2DSMVQWIX3LMV43ERDJONRXK43TNFXW4OZXG44DEMZZGU>. You are receiving this because you are subscribed to this thread.