Fig. 5
From: Instrumented swim test for quantifying motor impairment in rodents
Spherical representation of animal head orientation to visualize swimming performance. (A) Left cartoon shows the three coordinate axis vectors (nose forward, ear leftward, and head upward) representing animal head orientation. Right are three sphere plot views of the same data, showing just the head upward unit vector (ear and nose vectors are not used) from a single control animal trial, traced over time onto a unit sphere. (B) Left cartoon shows new forehead vector (blue) which is pitched upward 45 degrees to be nominally aligned with gravity during swimming. Right are three views of the same data from panel A, but now using the forehead vector’s trace rather than the head vector, showing tighter alignment to the sphere “north pole". (C) Forehead vector plot of a mutant animal, showing considerable deviation from upright. Only the forehead vector is plotted, but data are colorized to indicate when the vector is significantly deviated from upright: the trace is orange where the animal forehead vector deviates from upright by 66°-90°, and red when deviation is more than 90°.
