Dear SPM experts,
I have experimental data that I need to analyze and I wanted to ask you to review if my plan of analysis is correct because I'm not confident if it is the optimal way to analyze the data.
Details:
The experiment aim is to check the difference in activation patterns during a choice-task between 2 subjects groups in 3 experimental conditions (2 manipulations and 1 control).
Each trial starts by presenting 6sec choice-task, then subjects have 2sec to made their decision in the task by clicking a button and lastly 4-8s of fixation (our jitter) before the next trial.
We only have a single run which composed of 72 (randomized in order) of the mentioned (consisting 3 types of our choice-task).
Our TR=2.7sec and the ITI=4-8sec.
For the 1st level analysis, in an event related design where each period of the choice-tasks (6s) is considered a single event , my aim is to convolve the hrf with the choice-task periods to see the brain activations. I plan to create 3 conditions (A,B,C) by entering the onsets of the 3 types of choice-task events we have.
However, due to our long TR I'm not sure if this way is good enough for modeling the neural response? I mean, shouldn't I need to change the high-pass filter or employ a slice-timing correction? Or maybe you have a more accurate way to enter the onsets (maybe with a shift of a few seconds)?
Thank you very much in advance and Merry Christmas,
Jason,
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