RE: Latency (command: responsetime)

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Latency (command: responsetime)

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LaraG	LaraG posted 11 Years Ago Topic Details Share Topic
Group: Forum Members Posts: 2, Visits: 6	Dear users, I noticed a problem with my recorded stroop data: I adapted an inquisit file, formerly used for inquisit 3, with the stroop paradigm. Checking the recorded data, I found latency means about 250ms, some are 0 ms, only a few latencies are 'normal', what means about 600 ms or higher. I don't know where the problem was, because almost the same inquisit file was used in another study, but there was used inquisit 3, not 4. May that be the mistake? That's my trial text: <trial tr_gg> / pretrialpause = 200 / stimulustimes = [0=te_fixation, te_redreminder, te_greenreminder; 500=te_greencongruent] / correctresponse = ("g") / validresponse = ("g","h") / errormessage = true(te_error, 400) / correctmessage = true(te_correct, 400) /responsetime = 700 / response = timeout(2700) </trial> Compared to the standard stroop file from the millisecond task library, I found, that the responsetime and response - commands aren't there. In the inquisit 4 help tool, there isn't the response time-command at all. Can you help me? How can I transform that small latencies to the real latencies (if possible)? Thank you very much, Lara
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Dave	Dave posted 11 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 13K, Visits: 109K	/responsetime = 700 means that Inquisit was instructed to start listening for a response at 700 ms into the trial, i.e. 200 ms after the stimulus 'te_greencongruent' was first displayed. / stimulustimes = [0=te_fixation, te_redreminder, te_greenreminder; 500=te_greencongruent] Latency is relative to the point in time specified in /responsetime. I.e. a recorded latency of, say, 300 ms means the person responded 500 ms after 'te_greencongruent' was rendered to the screen. /responsetime is the old, deprecated name for the attribute. In current Inquisit 4 releases, the attribute is called /beginresponsetime and you can find all relevant documentation under that name.
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LaraG	LaraG posted 11 Years Ago ANSWER Post Details Share Post
Group: Forum Members Posts: 2, Visits: 6	Thank you very much! That means: If I added 200ms to each latency, I would have the "real" latencies?
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Dave	Dave posted 11 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 13K, Visits: 109K	> That means: If I added 200ms to each latency, I would have the "real" latencies? Well, at least you get an acceptable approximation. Not sure about using the word "real" in this context -- but that's a philosophical matter for the most part.
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