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Group: Forum Members
Posts: 2,
Visits: 7
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Hi All!
I'm a new member so forgive me if my question is lame, but I couldn't find a solution for my problem.
I'm trying to program a reaction time based sensomotory coordination task: presenting a stimuli (a random number from 1 to 4), and the subject must push the corresponding buttons as soon as possible.
I've already created a fully functioning version in which there's only one correct answer
(so for example the number "1" comes up on the screen and pressing the button 1 means the correct response, whereas pushing 2, 3, 4, or no response is incorrect.)
What I would like to create is a version in which the subject must press two buttons simultaneously, one with the left and one with the right hand. For example: when the number 1 comes up on the screen, you must press "e" with your left, AND "i" with your right hand at once (I just mentioned these letters randomly, imagine both of them labeled "1" on a special keyboard).
Is it possible?
I tried this (imagine that e-r-d- f is 1-2-3-4 with left, and i-o-k-l is 1-2-3-4 with right hand):
<trial one_1>
/ stimulusframes=[1=one]
/ validresponse = ("e", "r", "d", "f", "i", "o", "k", "l", noresponse)
/ correctresponse = ("e" & "i")
/ trialduration = 1500
</trial>
But it's not working, seems as both answers are registered as correct, even if you only press one of them.
Of course somehow I think I'll also need to specify the lenght of time gap between button presses which is still considered to be acceptable. I'd be grateful for that as well.
Thanks in advance for your help!
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