Probe trials
Running a probe trial
A few minutes without the platform, planned carefully.
The original notes give the basics: no platform, 1 to 2 minutes, with you rescuing the animal at the end, done only on trained animals and not too often. Anderson's 1998 sequence tracked the swim for one minute after the final training session. How many probe trials can you run before the animals start to learn that the platform isn't there? One study (Han and colleagues, 2024, a preprint) argues for no more than two.
- Han et al. (2024). The probe trial in a water maze test should not exceed two times. Research Square Platform LLC . doi:10.21203/rs.3.rs-4134660/v1
Questions people ask
How do I run a probe trial?
Enter the learned platform position, tick Probe and turn Auto-end off. 1) Enter the learned position as usual. 2) Tick Probe. 3) Select 'No' under 'Auto-end on platform'. 4) Set 'Max Seconds' (e.g. 60), then run as normal.
More detail
Enter the learned target location as you would a real one (single trial or TXP) so it appears in results and diagrams. Tick Probe, select 'No' under 'Auto-end on platform', enter the duration in 'Max Seconds' (e.g. 60), and run as normal.
Going deeper
In probe trials, measures such as platform crossings, close encounters, Gallagher proximity and the Direct Path Measures are interpreted relative to the learned location. References: Direct Path Measures v1.0 (doi:10.5281/zenodo.21870806).
See also platform crossings in Morris water maze analysis on hvsimage.com.
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