Trial time at which ImageChanger presented images

Is there a way for me to access the trial time at which ImageChanger presented each of its images in ImageList? Basically like running trialtime each time ImageChanger moves onto a new row in ImageList.

You can set eventmarkers in each row of the image list.
https://monkeylogic.nimh.nih.gov/docs_RuntimeFunctions.html#ImageChanger

Is this accessible during the trial? I can't seem to find where the eventmarker times are stored for the current trial.

Can you explain the details more? What is the purpose of getting the time during the trial? Eventmarker times usually become available after a trial via the TrialRecord structure.

It was great to meet you at SfN. As we spoke about at the conference, my task involves making a saccade to the correct image after it has been presented. I need to deliver the reward only if the saccade was initiated 100-400ms after the image appeared on the screen so I know the reaction time was long enough to be in response to the image rather than a timed guess. As we spoke about, the eye trace can be used to determine when the saccade started, but I’m not sure how to modify the ImageChanger adapter so that I have access to the time of image presentation. I’ve made a simplified version of the task that has all of these characteristics and attached it to this post. It includes a minimally modified version of ImageChanger that moves CurrentImageNum from protected to set access protected.

Thank, Mitch. Please give me some time to take a look at the files.

I added a property (OnsetTime) to ImageChanger so that you can tell when the "correct" image was presented. The OnsetTime (an n-by-1 vector) is NaN for the images not presented during the scene.

I think the easiest way to retrieve the eye trace is to use get_analog_data().

correct_image = 10;
onset = img.OnsetTime(correct_image);

if isnan(onset)
    % The correct image was not presented
else
    warning off;  % to suppress occasional 'insufficient sample' warnings
    eye = get_analog_data('eye',round(trialtime));  % in degrees
    warning on;
    eye_after_correct_image = eye(round(onset):end,:);

    % do something with eye_after_correct_image
end