Knowledge Base

Problem

Researcher wants to display animated images or video stimuli on external monitors (connected to the same PC) for behavioral assays such as predator tests in zebrafish, while simultaneously tracking animal movement in EthoVision XT. They want to know how to trigger the display from within EthoVision and what software to use.

Details

EthoVision XT does not have a built-in animated stimulus display module. However, the Trial Control settings can issue a command-line/batch-file trigger to launch an external application that handles the display. EthoVision does not have specific validated recommendations for external display software. Affects any version of EthoVision XT with Trial & Hardware Control module.

Solution

1. Prepare your animated stimulus using any external application capable of displaying images or video on a specified monitor and accepting a command-line launch (e.g., VLC, PowerPoint, a custom Python script, or any media player that accepts command-line arguments).
2. In EthoVision XT, open Trial Control settings.
3. Add a 'Run application' or 'Command prompt' action in the Trial Control rule at the desired trigger point (e.g., trial start, zone entry).
4. Configure the command to call your batch file or executable with the appropriate arguments (e.g., specifying which monitor to display on, which file to play).
5. Refer to the EthoVision XT Help guide section on Trial Control for detailed syntax on formatting the command prompt action.
6. Noldus does not provide support for the configuration or programming of the external display application itself — only the trigger mechanism within EthoVision is supported.