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Randomize routines in a saccade task

Hi everyone. first of all, sorry about my english.

I have a trouble with a saccade task in Psychophy ver 1.90

my experiment consist of 7 routines in the flow

each routines consist of 4 visual stimulus. i need to

randomize the routines, not the stimulus, because the stimulus of each rutine need to be in order.

how i get this???

Please specify what you mean by this. Think how you would describe it in the methods section of a paper.

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thanks so much for the answer. i try to explain the best that i can

I try to program a antisaccade task
this task consist in a fixation point in the screen, follow of a signal to indicate to the subject to make a response.
this signal indicates if the trial is a saccade or antisaccade trial.
And finally a point in the screen (left or rigth) to make the response.
all the stilumus are presented in time order (few seconds)
The motor response is to look in direction of the last point, in other words a saccade (look in direction of the stimulus) or a antisacade (look in the oposite direction of the stimulus). We have only 2 responses.

we gonna use a eye tracker to measure the motor response.

i succes in the program the 7 conditions.

1: sacade to the rigth
2: saccade to the left
3: antisaccade to the rigth
4: antisaccade to the left
5: Preparatory saccade (is just the signal that indicate that the trial is a saccade trial without response)
6: preparatory antisaccade (just the signal that indicate that the trial is a antisaccade trial)
7: is just a central fixation point in the screen like a control

i put the 7 conditions in the flow like the image.

each condition (1,2,3,4,5,6,7) need the correct order of the presentation (first a fixation point, the signal, and the stimulus target, all dots in the screen)

then i put a loop to repeat each condition 5 times.

until this point i dont have problem

however i need to randomize the loop, in other words, randomize the conditions (1,2,3,4,5,6,7)

to make appear sometimes first the saccade rigth condition and follow antisaccade left, etc, and sometimes firts the antisaccade rigth and then preparatory saccade, etc.

my trouble is that i dont know how i can randomize the 7 conditions without change the internal order of the stimulus.

thanks so much. i really appreciaty the help :slight_smile:

This isn’t really the PsychoPy approach to things. The key is to realise that this is only a single task, not seven different types.

So what you want is a single experimental routine for this task. You just need to control the behaviour of the stimuli to fit the conditions on any given trial. That also has the advantage that all of your variables in the data output file will end up in the same columns: this will greatly simplify your analysis procedures.

e.g. you have a stimulus for the fixation point, two stimuli for the directional cue (one for each trial type), and one for the target.

In the conditions file, have a column specifying whether this is a saccade or anti-saccade trial, called, say trial_type. For the saccade trial cue stimulus, put this in its opacity field:

 trial_type == 'saccade' 

and in the anti-saccade cue opacity field:

 trial_type == 'anti-saccade' 

Each of these expressions evaluates to 1 if true (so it will be visible) and 0 if false (so will be invisible on that trial).

For the target, control its position to the left or the right using a position variable in your conditions file.

The fixation stimulus is simple, as it is constant in appearance and location (although you might be varying its duration presumably).

The randomisation happens in the loop dialog, controlling the order of rows in your conditions file.

Make sense?

thanks so much for the help.

i will try to do in that way.