Knowledge Base

Problem

Users setting up a Barnes maze experiment in EthoVision are unsure whether a hidden zone is required over the goal box, and how to detect and count nose dips or head dips into empty holes.

Details

The Barnes maze involves a circular platform with multiple holes, one of which leads to an escape box. Users want to track goal box entry/exit times and count investigatory nose dips into empty holes. Applies to EthoVision XT with the Multiple Body Points module for nose-point detection.

Solution

1. Hidden zone for the goal box:
- A hidden zone over the goal box is optional but useful. It allows EthoVision to track precisely when the animal fully enters and exits the escape box (when the subject becomes temporarily invisible from above). This provides accurate entry/exit timing.
- If you only need to track when the animal is near the goal box hole, a standard zone drawn over the hole location is sufficient.
2. Counting nose dips into empty holes:
- To detect head/nose dips into holes, use the Multiple Body Points tracking module (nose-point detection).
- Draw small zones (e.g., circular zones) over each hole on the Barnes maze.
- Configure analysis parameters to detect when the nose point enters a hole zone. This approach works similarly to the Hole Board test setup.
- Use the 'Nose-point zone contact' parameter to count entries of the nose point into each hole zone as a measure of investigatory dipping.
3. Ensure the Multiple Body Points module is active in your license (Help > About EthoVision XT > License Info).