Atlantis platform

The question

Time to stretch our legs. What if the platform only rose when the animal searched in the right place? You're watching Morris Water Maze Software Guide, over at morriswatermazesoftware.com.

Meet the Atlantis platform

The Atlantis platform sits deep in the pool where the animal can't reach it. It only rises when the animal has stayed in the target zone for a set time. That means the animal can't find it by chance, so every training trial works a bit like a probe. A 1994 paper described the electromagnetic Atlantis design with software-controlled video tracking.

How it runs

How do you run one? First, set a target zone around the platform and a dwell time. Next, lower the platform out of reach at the start of each trial. Then, let the tracking software raise it when the animal dwells in the zone. Finally, run probe trials as usual, with the platform kept down.

Strengths and limits

What's it good for? It prevents finding the platform by chance. Training trials give spatial data, not just latency. It can produce a more focused search in probes. Now, the small print. Long dwell times can frustrate animals. Tracking errors can raise or hold the platform wrongly.

What to measure

This is where tracking software earns its keep. Time to trigger the platform: the Atlantis version of latency. Time in the target zone: how much searching happened in the right place. Proximity: distance from the target throughout the trial. Dwell attempts: how often the animal entered the zone without staying. With a normal platform, a rat can learn to bump into it by circling. With Atlantis, circling never lifts the floor. Only staying in the right place does.

The takeaway

If you remember only one thing, make it this: time in the target zone and its neighbours tell you how the task was done, not just how fast. Everything we covered is written up below.