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[solved] record keyboard response time while audio file is running

edited November 2014 in OpenSesame

Hi -
I'm running an experiment in which a subject is presented with an image (two items side by side) and at the same time they hear an audio file "Now press the button for the please" . The subject is then supposed to press either "1" if is the left image or "0" if it's the right image. I have the experiment up and running and all seems well except for logging the response_time_left_right_response. What I'm interested in logging is the time from the onset of the target word to the listener's keyboard response (0 or 1). I want the image to stay on screen and the audio to finish playing, so keyboard_response shouldn't affect that.

Below I've given the scripts for the main part of my experiment as well as some lines of the logger output.

As far as I can tell the logger is logging the response_left_right_response correctly, but the response_time (column 7, see below) is almost always 0, which is definitely incorrect. It's unclear to me what it is logging, documentation suggests: "interval in ms between start of response interval and the last response".

Basically what I need to know is how to get opensesame to log the keyboard_response_time in relation to the audio file start time. Any advise how best to do this? I'm running opensesame on a Mac.

correct_left_right_response count_experiment    count_trialsequence cr  picture response_left_right_response    response_time_left_right_response   sound   time_left_right_response
1   0   0   1   2broom-sun.bmp  1   10  carr_broom_3.wav    1785607
1   0   1   1   2peach-bed.bmp  1   0   carr_peach_2.wav    1789694
1   0   2   0   2pear-sun.bmp   0   0   carr_sun_2_um_chef_3.wav    1793874
1   0   3   1   2pear-church.bmp    1   0   carr_pear_2_um_chef_3.wav   1798029
1   0   4   0   2tree-swan.bmp  0   0   carr_swan_3.wav 1802035
1   0   5   0   2rake-foot.bmp  0   0   carr_foot_3_um_chef_3.wav   1805913
1   0   6   1   2fish-broom.bmp 1   0   carr_fish_3.wav 1809791

The order of the sequence (within a loop):

run fixation_dot "always"
run picture_pair "always"
run audio_files "always"
run left_right_response "always"
run logger "always"

script for picture_pair:

set duration "0"
set description "Displays stimuli"
draw image 0 0 "[picture]" scale=1 center=1 show_if="always"

script for audio_files

set volume "1"
set description "Plays a sound file in .wav or .ogg format"
set sample "[sound]"
set pitch "1"
set duration "sound"
set stop_after "0"
set pan "0"
set fade_in "0"

script for left_right_response:

set correct_response "[cr]"
set allowed_responses "1;0"
set description "Collects keyboard responses"
set timeout "infinite"
set flush "yes"

Thank you for your help! Mirjam


  • edited 8:12PM

    After further searching the answer was here:

    "The duration of the sampler/ synth is perhaps a bit counter-intuitive.

    There is also 'duration = 0' which means that the sampler/ synth will not block at all, and simply have the sound playing in the background. This means that the experiment advances right to the keyboard_response, and your problem should be solved."

    And this did solve it for me. Maybe this could be added to the documentation? It would have saved me quite some time.


  • edited 8:12PM

    Love the problems that sort themselves out. Thanks for letting us know!

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