Fixation point flickering in Eye Window

Support
1

Hi Chris,

The fixation stimulus flickers and disappears or doesn’t appear at all in the Eye Window (please see the attached video). I am using 0.12.2 version of MWorks.
Time points: 29-31s, 1min 9-11s

Best,
Vladyslav

2

Hi Vladyslav,

That’s strange. Can you send me the experiment file that produces this behavior? Also, on what version of macOS are you running MWClient?

Thanks,
Chris

3

Hi Vladyslav,

Thanks for sharing your code. Unfortunately, I’m not seeing anything in it that suggests a cause for this problem.

One question: If you make the fixation point visible (i.e. set its alpha multiplier to 1), does it also flicker on the main display and/or mirror window? Or does it only happen in the eye window?

If it only happens in the eye window, here’s another thing you can try: Instead of opening MWClient via the Finder or Dock, open Terminal, and launch it from the command line:

/Applications/MWClient.app/Contents/MacOS/MWClient

This will let you see any messages (error, warning, or otherwise) from MWClient in the Terminal window. When the fixation point flickers in the eye window, does MWClient output any messages? If there’s an internal issue with the UI code, there may be some diagnostic output about the problem.

Thanks,
Chris

4

Hi Chris,

  • Setting alpha to 1 doesn’t change anything. The fixation point (and the live stimulus MonkeyDoppelganger and MonkeyDoppelganger_update - small dot on the video) flickers only in the Eye Window. There is no flickering in the mirror window nor on the actual display.
  • Interestingly, after I removed the live stimulus the fixation point stopped flickering all the time, but it disappeared only in the Eye Window and reappears very rarely even after requeueing it.
  • Opening the MWClient through terminal does not remove flickering. Also there are no relevant messages in the Terminal or the MWServer’s console. The only message I see is about Matlab:
2026-07-20 17:22:49.958 MWClient[58267:358283545] Couldn't load bundle: The bundle “MWorksMATLABWindow” couldn’t be loaded because it doesn’t contain a version for the current architecture.: {
    NSBundlePath = "/Library/Application Support/MWorks/Plugins/Client/MWorksMATLABWindow.bundle";
    NSDebugDescription = "dlopen_preflight(/Library/Application Support/MWorks/Plugins/Client/MWorksMATLABWindow.bundle/Contents/MacOS/MWorksMATLABWindow) => false, tried: '/Library/Application Support/MWorks/Plugins/Client/MWorksMATLABWindow.bundle/Contents/MacOS/MWorksMATLABWindow' (mach-o file, but is an incompatible architecture (have 'x86_64', need 'arm64e' or 'arm64')), '/System/Volumes/Preboot/Cryptexes/OS/Library/Application Support/MWorks/Plugins/Client/MWorksMATLABWindow.bundle/Contents/MacOS/MWorksMATLABWindow' (no such file), '/Library/Application Support/MWorks/Plugins/Client/MWorksMATLABWindow.bundle/Contents/MacOS/MWorksMATLABWindow' (mach-o file, but is an incompatible architecture (have 'x86_64', need 'arm64e' or 'arm64'))";
    NSFilePath = "/Library/Application Support/MWorks/Plugins/Client/MWorksMATLABWindow.bundle/Contents/MacOS/MWorksMATLABWindow";
    NSLocalizedDescription = "The bundle \U201cMWorksMATLABWindow\U201d couldn\U2019t be loaded because it doesn\U2019t contain a version for the current architecture.";
    NSLocalizedFailureReason = "The bundle doesn\U2019t contain a version for the current architecture.";
    NSLocalizedRecoverySuggestion = "Try installing a universal version of the bundle.";
}

Best,
Vladyslav