Markowska et al. (1993): the variable-interval probe

A paper the old site hosted as a PDF, and still does.

By the watermaze.org editors · Updated 4 November 2026

Markowska AL, Long JM, Johnson CT, Olton DS (1993). Variable-interval probe test as a tool for repeated measurements of spatial memory in the water maze. Behavioral Neuroscience 107(4): 627–632.

In plain words: in a standard probe trial the platform is gone for the whole trial, so the rules change for the animal. In a variable-interval probe, the platform is unavailable at first and then becomes available after a variable time. The authors found this was more sensitive than the no-platform probe and could be repeated during training (from the paper's abstract).

The old watermaze.org hosted a PDF of this paper, and it is back at its original address. For more on probe trials, see the probe trials section.

Read the paper: Markowska_BN_1993.pdf (PDF, 6 pages, 540 KB), the copy hosted on the original watermaze.org.
Publisher's record: doi.org/10.1037/0735-7044.107.4.627

For the measures most often taken in a probe, see preference for the target quadrant and platform crossings on hvsimage.com.

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