By Paul123 - 10/13/2014
Dear All,
I am trying to write a script where participants are asked to press one of four buttons and then they are shown a pair of pictures. Afterwards, I would like to give them feedback depending on the button that they pressed at the beginning of a trial ("keep a point" feedback if they press "k" button, "lose a point" feedback if they press "m" button and "incorrect button" if they press "a" or "z"). My script seems to work fine for "k" and "m" responses but I do not know how to include the feedback for incorrect buttons. </trial 1> / validresponse = ("k","m") / correctresponse = ("m") / responsetime = 1001 / inputdevice = keyboard / stimulustimes= [1 = FixationB; 1001 = Fixation50] / branch = (trial.1.correct, eq , 1, neutralVSstimulus) / branch = (trial.1.correct, eq , 0, neutralVSstimulus) </trial> <trial neutralVSstimulus> / response = timeout (3003) / stimulustimes= [1 =ControlLeft2, StimulusRight2, xdat4; 2002 = blank, xdat0] / branch = (trial.1.correct, eq , 1, WinPoint) / branch = (trial.1.correct, eq , 0, LosePoint) </trial> <trial WinPoint> / response = timeout (3003) / stimulustimes= [1 = WinPoint] </trial> <trial LosePoint> / response = timeout (3003) / stimulustimes= [1 = LosePoint] </trial>
Your help is highly appreciated!
Paul
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By Dave - 10/13/2014
Schematically you simply do:
<trial mytrial> / validresponse = (ENTER SCANCODES FOR ALL FOUR KEYS) ... / branch = [if (trial.mytrial response == SCANCODE FOR K) trial.x] / branch = [if (trial.mytrial response == SCANCODE FOR M) trial.y] / branch = [if (trial.mytrial response == SCANCODE FOR A || trial.mytrial.response == SCANCODE FOR Z) trial.z] </trial>
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By Paul1234 - 10/13/2014
Hi Dave, Thank you for your answer. I have used a similar solution before - I have branched four separate responses with four separate neutralVSstimulus trials. In my task neutralVSstimulus trial contains 5 picture pairs which were supposed to be presented without repetition regardless of the response given by participants. However, when I run the task I realised that some of the picture pairs were presented more than once. That is the main reason I used trial.mytrial.correct, command in order to make sure that each of the picture pairs is presented only once.
*** PICTURES *** <item set1> / 1 = "l1a.jpg" / 2 = "l3a.jpg" / 3 = "l4a.jpg" / 4 = "l6a.jpg" / 5 = "l7a.jpg" / 6 = "l8a.jpg" / 7 = "l13a.jpg" / 8 = "l14a.jpg" / 9 = "l18a.jpg" / 10 = "l19a.jpg" </item> <item controlset1> / 1 = "l1b.jpg" / 2 = "l3b.jpg" / 3 = "l4b.jpg" / 4 = "l6b.jpg" / 5 = "l7b.jpg" / 6 = "l8b.jpg" / 7 = "l13b.jpg" / 8 = "l14b.jpg" / 9 = "l18b.jpg" / 10 = "l19b.jpg" </item>
<picture StimulusRight1> / items = ("l1a.jpg","l3a.jpg","l4a.jpg","l6a.jpg","l7a.jpg") / position = (80, 50) / select= noreplace </picture> <picture ControlLeft1> / items = ("l1b.jpg","l3b.jpg","l4b.jpg","l6b.jpg","l7b.jpg") / position = (20, 50) / select = StimulusRight1 </picture>
<picture StimulusRight2> / items = ("l8a.jpg","l13a.jpg","l14a.jpg","l18a.jpg","l19a.jpg") / position = (80, 50) / select= noreplace </picture> <picture ControlLeft2> / items = ("l8b.jpg","l13b.jpg","l14b.jpg","l18b.jpg","l19b.jpg") / position = (20, 50) / select = StimulusRight2 </picture>
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By Dave - 10/13/2014
> However, when I run the task I realised that some of the picture pairs were presented more than once. That is the main reason I > used trial.mytrial.correct, command in order to make sure that each of the picture pairs is presented only once.
I fail to see what one has to do with the other. Whether a correct response is given or not / whether you use the trial.mytrial.correct property has no bearing per se on how stimuli are selected.
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By Paul1234 - 10/13/2014
Ok, thank you - I will give it a go once again.
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