Isi

SuperLab SuperLab 4 Support
1

Hello,

I am designing a simple verbal n-back task. It consists of a series of letters and the participant is required to respond Yes/No to each letter presentation. Yes, if the current letter is the same as the n-th letter back . No if it’s not. The aprticipant should be able to give their response either while the letter is still on the screen or during the blank ISI screen that follows.

I have designed my experiment with the letters saved as lists saved as an event. In addition, I have added an ISI as an event. Each of my trials consists of a letter from the list + the ISI. I have specified in the list event which responses are correct and which are not (this is based on the order of the letters).

If the participant responds during the time the letter is still on the screen (i.e. the stimulus is presented) it records correctly the respond and determines whether it’s an error or not. The problem is that if the participant responds during the ISI event the program takes any response as correct. I want the program to recognize which response is correct regardless of whether the participant responds during the stimulus presentation event or during the ISI event. Given the ISI is just something added in between, how can Superlab read that the responses during the ISI should match with the event stimulus that was presented just previously. Is there a way…hopefully I have managed to explain this clearly.

Thanks,
Vess

2

You can do this by duplicating your stimulus list and using it in place of the ISI. However for this event, make sure the letters are being presented off the screen. This way it will act like an ISI but it will collect the participants responses correctly.

3

How do I make sure the letters are being presented off the screen

Thank you for responding. How do I make sure the letters are being presented off the screen? should i just make the font and the background the same color or is there another way?

thanks,
vess

4

In the Event Editor, under the Stimulus tab, click on the Settings button. From here, go to the Position button and use the x,y coordinates to display the letters off the screen.

5

n-Back with ISI

Hi,

I am also designing a simple verbal n-back task, with a letter displayed for 1/2 s followed by a 2.5s blank screen ISI. I had the same question as Vess so that part I will use, but it also brought up a design question.

I have my n-back designed as each trial containing 18 letter events for 0.5s, and each letter event is followed by a blank screen ISI for 2.5s. Is it possible to use a stimulus list instead? How do I have the stimulus list display each letter for one length of time and the blank screen for a different length of time?

Thank you!

Jessica