Responses in very short trials


Author
Message
Blackadder
Blackadder
Supreme Being (27K reputation)Supreme Being (27K reputation)Supreme Being (27K reputation)Supreme Being (27K reputation)Supreme Being (27K reputation)Supreme Being (27K reputation)Supreme Being (27K reputation)Supreme Being (27K reputation)Supreme Being (27K reputation)
Group: Forum Members
Posts: 280, Visits: 147

Hi All, consider the following (functional) script:


<text TEXT_A>
/ erase = false
/ items = ("A")
/ txbgcolor = white
</text>

<text TEXT_B>
/ erase = false
/ items = ("B")
/ txbgcolor = white
</text>

<shape SHAPE_dummy>
/ color = white
/ erase = false
/ position = (0%, 0%)
/ size = (1px, 1px)
/ shape = rectangle
</shape>

<trial TRIAL_main>
/ branch = [if (trial.TRIAL_main.response==57) trial.TRIAL_main]
/ responseframe = 1
/ responseinterrupt = trial
/ stimulusframes = [1=TEXT_A; 3=TEXT_B; 4=SHAPE_dummy]
/ timeout = 0
/ validresponse = ("a", 57)
</trial>

<block BLOCK_main>
/ trials = [1 = TRIAL_main]
</block>

<expt>
/ blocks = [1 = BLOCK_main]
</expt>



The code above presents an "A" for 2 frames, then presents a "B" for 1 frame, followed by a stimulus dummy for another frame. The dummy is there to have "A" and "B" stay on the screen for 2 frames each.


Then, the trial branches onto itself and starts anew, the result being a rapid flicker between "A" and "B".


The script is supposed to stop if the "a" key is pressed (scancode 30) and meanwhile just record every press of the space bar (scancode 57).


My question: why does this script not record any keypresses?


If I understand the help correctly, response recording should start at frame 1. Hence, if I pressed the space bar somewhere between frame 1 and 4, the trial should return a 57 as its response. Well, it doesn't, and neither does "a" terminate the script. Why is that?


Bye, Malte


GO

Merge Selected

Merge into selected topic...



Merge into merge target...



Merge into a specific topic ID...




Threaded View
Threaded View
Blackadder - 12 Years Ago
Dave - 12 Years Ago
Blackadder - 12 Years Ago
Dave - 12 Years Ago
Blackadder - 12 Years Ago
                         [quote]The peculiar thing is that with /timeout = 66, the trial...
Dave - 12 Years Ago
                             [quote]This would be consistent with a loss / lag of one frame on a...
Blackadder - 12 Years Ago
                                 One more question for those with insight into the Inquisit code. If in...
Blackadder - 12 Years Ago
                                     /timeout vs. /trialduration should not make any difference here. As...
Dave - 12 Years Ago
                                         I am aware of the flow diagram in the docs. The key issue to me is...
Blackadder - 12 Years Ago
                                             [quote] the actual metric for the experimentator is always discrete,...
Dave - 12 Years Ago
                                                 [quote]Yes and no.[/quote]
Let's just stay with the "yes" part...
Blackadder - 12 Years Ago
                                                     [quote]Will the frame refresh and the timeout compete with each...
Dave - 12 Years Ago
                                                         [quote]you need to use pre- and posttrialpause (which are part of...
Blackadder - 12 Years Ago
                                                             [quote]Inquisit won't record responses during pre-/posttrialpause, if...
Dave - 12 Years Ago

Reading This Topic

Explore
Messages
Mentions
Search