Direct Finding / Direct Heading: The animal swims straight to the platform or learned location with minimal deviation.

This typically emerges in later acquisition trials or well-trained animals, and suggests hippocampus-dependent learning. It indicates:

• Strong spatial memory.
• Accurate allocentric navigation using distal cues.
• Formation of a stable spatial representation of the environment.

Target Scanning: The animal swims near the platform location, often circling or moving back and forth in that approximate area.

Target scanning may identify intermediate stages of spatial learning. It suggests that:

• The subject remembers the general location of the platform but is not pinpointing it precisely.
• The subject has a partially developed spatial map.
  or
• Strategy refinement may be in progress.

Focused Search: The animal searches with more precise focus on the immediate surrounding area of the platform.

Focused search is often seen after partial learning, in probe trials, or in animals with mild hippocampal impairment:

• Indicates platform-location memory, but with less efficient path planning.
• May represent uncertainty or imprecise cue integration.

Chaining: The animal swims in a circular path at a fixed distance from the wall, corresponding roughly to the platform’s radial distance. It looks adaptive (the platform can be found reliably, when present) but it’s not a spatial strategy.

Chaining is common in subjects with hippocampal dysfunction, early in training, or when spatial cues are absent or ambiguous. It suggests:

• A non-spatial, procedural strategy – the strategy allows the platform to be found by covering all points at the learned distance from the poolside, not via spatial memory.
• Egocentric navigation, possibly mediated by the dorsolateral striatum.

General Scanning: The animal swims in broad loops or meandering paths across multiple quadrants without consistent focus on any specific area (unlike target scanning, which is concentrated near the platform location).

General scanning may be seen during strategy formation and in disoriented or disengaged behavior.

• Suggests the animal is searching randomly or employing a non-specific strategy.
• May reflect uncertainty, early training, or cognitive impairment.

Thigmotaxis: The animal swims along the edge of the pool, hugging the wall.

Excessive thigmotaxis can mask or delay spatial learning and is a key behavioral marker to track, particularly in anxiety or neuromodulation studies:

• Often indicates anxiety, stress, or lack of task engagement.
• Also common in very early training trials before learning begins, as a natural protective behavior on initial exposure.

Inactivity: The subject swims very slowly, or not at all, for much of the trial.

A significant proportion of inactivity or floating may be a sign of disengagement, confusion, sensory or motor impairment, or fatigue.