Search the Legacy Support Archive (up to v2020)
  1. Read-only archive (2005–2024). Posting is closed. Need help with MediaLab or DirectRT 2027? Email service@empirisoft.com.

    All words · “exact phrase” · -leave out

    Advanced search

How do I record random trial order in output file?

  1. #1

    How do I record random trial order in output file?

    I am running an experiment in which a participant is exposed to two blocks of trials (wgr and bgr) in which he looks at a series of images (2 blocks, 12 images/trials each). During each exposure a 50 ms sound is played and physiological reactions are recorded (a TTL is sent at each trial start and when the sound is played). There is no RT. I need the output data to record which image was displayed so I'll know how to analyze the physio recording. I have tried various options, including creating an '!Image' optional field, but I only get limited output (I looked in the log file, no much more info). Can you please provide some guidance!

    Thank you!

  2. #2
    jarvis24 Blair Jarvis, Administrator
    Check this out:

    http://www.empirisoft.com/support/showthread.php?t=140

    [kw: missing data, empty file, block values]

  3. #3
    I am aware of the Block issue, is the first think I checked. Values are 1 and 2. On the other hand, if I inglude an RT after each treatment (Press a key to continue), I have all the data recorded in the output file. What I need is to know if I can get a record of which images have been displayed without having the participant to press a key to advance to the next image.
    Thanks!

  4. #4
    jarvis24 Blair Jarvis, Administrator
    An excellent first thing to check, i.e., that the values are non-zero. Second thing to check--make sure the values are negative if no responses are being recorded (check the fine print in that link). Try -1 and -2 and see if that helps.