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  • RSVP time between segments

    Hi,

    I'm running an RSVP task where I want each word to be on the screen for 500ms followed by 200ms of blank screen followed by the next word at 500ms...and so on.

    In Superlab 4.5 this was done by using a timing trial variable of 500,200 and adding in an extra delimiter in the RSVP event

    For example: word1\\word2\\word3

    Setting the trail variable level selection to sequential would produce the desired outcome.

    In Superlab 5 this functionality doesn't seem to exist. When I run my experiment with the above set up the timing does not change between segments of the RSVP, but rather between events. (So sentence one is 500ms on 0ms off and then sentence two is 200ms on and 0ms off)

    Surely there must be a way to vary the on/off timing within an RSVP event in Superlab 5. Any help is greatly appreciated!

  • #2
    Yes, there is a way to vary the on/off timing in SuperLab 5. The new technique is to use "Text Events" instead of "RSVP" for the event type.

    Attached is a demo that demonstrates how this feature was implemented in SuperLab 4.5 and how it's done in SuperLab 5. In the demo there are two blocks. You can use SuperLab's "Run selected blocks only" feature to observe how each block operates.

    The first block does use the technique used SuperLab 4.5. The second block uses "Text Events" instead of "RSVP". This experiment can use either technique in SuperLab 4.5 and SuperLab 5. In the demo, the RSVP trials have been converted into "Text Stimulus" lists.
    Attached Files
    Last edited by MonikaT; August 26th, 2014, 11:35 AM.

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    • #3
      Thanks for this Monika. This happens to work really well for me currently but unless I'm missing something it seems this won't work with sentences of varying lengths.

      Some finer control over individual segments within RSVP events (like being able to display a light sensor patch or send a digital pulse on a specific word) would be an awesome addition to superlab.

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      • #4
        Attached is a demo experiment showing two different ways to accommodate varying sentence lengths. Block A shows one way, and Block B shows another.

        Block A uses a more straightforward approach. Within Block A randomization is is being used under the Randomization tab. This is to randomize the two-word phrases with the three-word phrases.

        Block B uses fewer lists than Block A, however Block B uses Tag Sets and Feedback. You can see how Tag Sets were created by going to the Experiment menu, then selecting Tag Sets. Within the event "B, word 2" under the Correct Response tab you will see how the tags are implemented. Also, look under the Feedback tab to view how it's set-up.

        Block B might provide some inspiration as to how you could use Tag Sets and Feedback to selectively send a pulse (present a digital output even). Let us know if you would like assistance inserting digital output into a specific portion of some RSVP experiment you are designing.
        Attached Files

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        • #5
          RSVP and EEG

          I am designing an EEG experiment using RSVP. I have the following questions regarding the demo file t-2011_varying_lengths:

          1. How do you control the word presentation time and ISI? As I can see, you set the time limit as 600 ms for each word. So how do you vary the ISI?

          2. If you already link up the columns for the word list, how do you link each word with its individual digital output code?

          3. If I only want to send out digital codes for some words, which are in different positions of the sentences, how do I do that? Should I use dashes (--) for those words I don't care about?

          Thank you very much.

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          • #6
            Varying Time Limit & Event Codes for RSVP

            It is not possible to vary the time limit for each RSVP segment, nor send out a specific event code.

            What I recommend instead is trying to emulate the RSVP behavior using a Text event that uses a stimulus list. You can then have another list of event codes for sending digital output and you can vary the time limit using a trial variable.

            The attached experiment demonstrates this. It first presents a children’s poem using the RSVP feature with a 500ms delay. Then it presents the same poem with a delay starting at 500ms and increasing by 100ms after each segment is presented.

            The sample experiment also has a list of event codes. To use it, create an event of type Digital Output. I did not include this event with the sample experiment because SuperLab will then require the output device to be present, e.g. StimTracker.
            Attached Files

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