Capturing Late Responses

[Andrew]

Hello,

I am currently designing an experiment which includes the capturing of
responses that are correct, but occur after the end of stimulus
presentation. For example, a Stroop cue may be presented for 600ms,
and the subject makes the correct response at 650ms, after the Stroop
cue has disappeared. I would like to be able to use the .ACC and .RT
attributes of the Stroop slide when creating new variables at the
trial level, and not have them default to zero if the subject does not
respond within 600ms of the onset of the Stroop cue.

I have partially figured out a way around this, by including a
textslide called "CaptureLateResponses" immediately after the Stroop
slide (let's call it "StroopSlide"). The duration of the StroopSlide
is 600ms and the duration of the CaptureLateResponses textslide is
400ms, for a total of 1000ms for the subject to make a valid response.
I have set the TimeLimit on the StroopSlide to be 1000ms, in order to
capture late responses. I have set the timing of both slides to
Cumulative, and I have set both to standard logging.

However, I am unable to store properties of the StroopSlide object
into variables at the trial level. For example, I wish to include only
trials in which both the current response and the previous trial's
response are correct. However, when I try to create this variable, I
find that, if the subject has not responded within the 600ms time
window that the StroopSlide object is present, both the accuracy and
response time attributes are set to zero. However, in the output edat
file, these values are processed normally, with responses slower than
600ms recorded in the StroopSlide.RT attribute, and correct responses
made after the 600ms time window recorded in the StroopSlide.ACC
attribute. Furthermore, when I insert a feedback slide after the
StroopSlide and CaptureLateResponses textslide, it appears to process
correct and incorrect responses normally, with late correct responses
still interpreted as correct.

Any feedback on why this is, and how to resolve this situation, would
be greatly appreciated.


Thank you,

-Andrew

-- 
You received this message because you are subscribed to the Google Groups "E-Prime" group.
To post to this group, send email to e-prime at googlegroups.com.
To unsubscribe from this group, send email to e-prime+unsubscribe at googlegroups.com.
For more options, visit this group at http://groups.google.com/group/e-prime?hl=en.