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[[BR]]
==FS-FAST USE CASE 1: fMRI Sorkflow for Reasoning Study==

===Experiment design===
The experiment consists of 3 active conditions (+baseline), referred to as V, T and P.
The task consists in solving visually presented problems in each of these conditions. Subjects respond using a button box.
The paradigm is presented in 6 consecutive runs, each lasting 300s. In each run, two of the three conditions are shown to minimize subject confusion, and increase statistical power**. The runs consist of
Run 1: T-P
Run 2: T-V
Run 3: P-V
Run 4: T-P
Run 5: T-V
Run 6: P-V
This alternation allows for similar scanner drift effects across the different pairings of the conditions (i.e. tentatively the same “amount” of drift occurs between runs 1 and 4 and 2 and 5, assuming drift is linear).
Within each run, the plates are presented using a pseudo-randomized (order the same for all subjects, but only known to the experimenter) event-related paradigm. Each plate presentation is considered an event, which can last between 1 and 10s, as the plate disappears when the subject responds or times out after 10 seconds (at which point the paradigm goes on by itself). In-between plates, a fixation cross is shown with a random ISI ranging from 1500 to 3500ms in 250ms steps. Every 6 plates, the fixation cross is held for a longer time, in order to match the total run duration across subjects**. Thus, the 7th plate appears at t=75s, the 13th at t=150s and the 19th at t=225s. The total run time of 5minutes is therefore the same as if all plates timed out (10x24 + 2.5x24 = 300).
The PAR files look like this:
Init_time condition_nb duration condition_name
0 0 2.5178 baseline
2.5178 2 2.3427 perceptual
4.8605 0 3.2763 baseline
8.1368 3 2.1638 verbal
10.3006 0 2.5216 baseline
12.8222 2 2.5746 perceptual
15.3968 0 2.0273 baseline

=THIS IS A WORK IN PROGRESS AND LIKELY HAS MISTAKES. PLEASE IGNORE FOR NOW=

BR ==FS-FAST USE CASE 1: fMRI Sorkflow for Reasoning Study==

===Experiment design=== The experiment consists of 3 active conditions (+baseline), referred to as V, T and P. The task consists in solving visually presented problems in each of these conditions. Subjects respond using a button box. The paradigm is presented in 6 consecutive runs, each lasting 300s. In each run, two of the three conditions are shown to minimize subject confusion, and increase statistical power**. The runs consist of Run 1: T-P Run 2: T-V Run 3: P-V Run 4: T-P Run 5: T-V Run 6: P-V This alternation allows for similar scanner drift effects across the different pairings of the conditions (i.e. tentatively the same “amount” of drift occurs between runs 1 and 4 and 2 and 5, assuming drift is linear). Within each run, the plates are presented using a pseudo-randomized (order the same for all subjects, but only known to the experimenter) event-related paradigm. Each plate presentation is considered an event, which can last between 1 and 10s, as the plate disappears when the subject responds or times out after 10 seconds (at which point the paradigm goes on by itself). In-between plates, a fixation cross is shown with a random ISI ranging from 1500 to 3500ms in 250ms steps. Every 6 plates, the fixation cross is held for a longer time, in order to match the total run duration across subjects**. Thus, the 7th plate appears at t=75s, the 13th at t=150s and the 19th at t=225s. The total run time of 5minutes is therefore the same as if all plates timed out (10x24 + 2.5x24 = 300). The PAR files look like this: Init_time condition_nb duration condition_name 0 0 2.5178 baseline 2.5178 2 2.3427 perceptual 4.8605 0 3.2763 baseline 8.1368 3 2.1638 verbal 10.3006 0 2.5216 baseline 12.8222 2 2.5746 perceptual 15.3968 0 2.0273 baseline

UseCase1 (last edited 2008-04-29 11:46:12 by localhost)