Measures

Latency was the first water maze measure, and it's still the one most people look at first. But latency alone can't tell a fast, wandering swimmer from a slow, direct one. These pages explain each measure in plain words first, then in more depth, with a worked example.

: Read latency together with path length and swim speed. A fast swimmer can look clever.

• Escape latencyTime to find the platform, and its limits.
• Path length & path ratioHow far, and how directly, the animal swam.
• Swim speedA check on motor ability and motivation.
• Quadrant timeWhere the animal spent its time during a probe.
• Platform crossingsHow often the animal crossed the exact platform spot.
• Heading angleDid the animal set off in the right direction?
• Gallagher proximityAverage distance from the platform, a sensitive accuracy measure.
• ThigmotaxisWall-hugging, and what it can mean.
• Circular zonesRings across the pool, from the wall to the centre.
• Inactivity & floatingWhen animals stop swimming, and why it matters.
• Platform zones (counters)Small circular zones around the platform and every other calibrated position.
• Search strategiesHow the animal searched, not just how fast.
• Chaining annulusA ring at the platform's distance from the wall, used to spot chaining.
• Direct pathSpotting direct, near-direct and focused searches.
• Non-spatial confoundsAnxiety, vision, swimming and motivation can masquerade as memory.

HVS Image covers each of these measures in its Morris water maze analysis guide, including the path efficiency ratio.