Hi Chris,
I’m trying to troubleshoot some issues with the MWorks eye window.
In our system, MWorks is receiving the eye signal from an Eyelink.
To see the continuous eye position signals in the eye window, I put the variables ‘eye_x’, ‘eye_y’, and ‘saccade’ in the X, Y, and Saccade fields of the eye window options.
(1) The problem is that the eye window does not show the signal for eye movement (red crosses), only the green circle of the fixation point.
Looking at the fixed point on the screen, the ‘eye_x’ and ‘eye_y’ values in the variable window change well, so it seems to be recognizing the Eyelink signal.
Are there any additional options I need to set?
I’m currently using Eyelink 1000 plus, and I’m using the most recently updated version of MWorks.
Please tell me how to visualize the eye position in the eye window.
(2) In addition to this, I have one more question. In the eye window, I’d like to see not only the eye position but also the eye velocities (eye trace) such as ‘eye_velocity_h’ and ‘eye_velocity_v’.
How can I visualize these components?
Thanks,
Jungryul
Hi Jungryul,
The problem is that the eye window does not show the signal for eye movement (red crosses), only the green circle of the fixation point. Looking at the fixed point on the screen, the ‘eye_x’ and ‘eye_y’ values in the variable window change well, so it seems to be recognizing the Eyelink signal.
Are the eye_x and eye_y values calibrated? That is, are they in units of visual degrees, so that they match MWorks’ display coordinates?
The value under the slider in the lower left of the eye trace graph shows the current length of the slider in degrees. Its default (and maximum) value is 20, so if you’re trying to plot raw EyeLink pupil coordinates (which have typically have values on the order of 1000), they aren’t going to be visible.
FYI, the red crosses show the location of calibration samples, not eye positions. Eye positions are indicated by black dots (no saccade) or blue lines (saccade).
In the eye window, I’d like to see not only the eye position but also the eye velocities (eye trace) such as ‘eye_velocity_h’ and ‘eye_velocity_v’. How can I visualize these components?
You can plot them by setting the Auxiliary Analog Signal X and Y fields to the relevant variable names. Again, the values will have to be on the correct scale.
I hope that helps!
Cheers,
Chris
Oh! It works great.
Thank you so much, Chris.
Jungryul
I have one more question.
As shown in the attached image, the Eye window shows the eye velocity in both the top and bottom windows (cyan: horizontal velocity, magenta: vertical velocity).
(1) I want to show the eye velocity trace only at the bottom, not the top, because the display is messy. How can I remove only the top eye’s velocity?
(2) I would like to be able to freely change the range of the Y-axis in the bottom window (currently it’s fixed at a maximum of 20 degrees). Can you tell me how to adjust this?
Thanks,
Jungryul
Hi Jungryul,
Unfortunately, neither of those changes are possible at present. I’ve opened an issue, so that we can add these configuration options in the future. In the meantime, if you need a custom velocity plot, you’ll need to use the MATLAB window or Python bridge.
Cheers,
Chris
Thank you!
I sincerely hope that this issue is resolved.
Thanks again.
Jungyul
