Assessment of Cognitive and Sensorimotor Defi cits - Animal Models of Acute Neurological Injuries: Injury and Mechanistic Assessments - page 238

3. Data interpretation . As performance improves, escape latency
and swim-path length generally decrease. Animals that display
behaviors inappropriate for water maze testing (including spin-
ning, thygmotaxic navigation around the perimeter of the
pool, and inability to swim) are removed from the water maze
study. Group differences on this test represent differences in
general associative learning, swimming ability, visual defi cits,
and/or motivation to escape the water. Given these results,
data from the spatial water maze should be interpreted with
caution.

1. Procedure . This day of testing will be nearly identical to the
cued water maze task, except that the surface of the escape
platform is submerged 1 cm below the surface of the water
(which is now made opaque by the addition of the tempera
paint). Additionally, extra cues are hung on the walls of the
room to enhance the saliency of the room's spatial cues. For all
spatial (submerged platform) trials, the platform will remain in
the same location for all ten trials per day. Animals are still run
in fi ve blocks of two trials. For each trial, an animal is released
nose against the wall into the pool at one of four counterbal-
anced release points and allowed to fi nd the platform based on
its relationship to the spatial cues rather than direct
visualization.
2. Variables measured . Total swim distance, latency to fi nd the
platform, and swim speed. Use of a computerized tracking sys-
tem allows for more sophisticated measures such as proximity
to target and left/right turn bias.
3. Data interpretation . As performance improves, escape latency
and swim-path length generally decrease. Defi cits in the spatial
water maze task (especially when cued water maze performance
is normal) are generally thought to refl ect disturbances in some
component of the hippocampally mediated spatial navigation
and memory system. Differences in performance between Trial
1 and Trial refl ect differences in short-term (working) memory.

3.7. Day 7 (See Note 7):
Water Maze—Spatial
Location 1

3.8. Day 8 (See Note 7):
Water Maze—Spatial
Location 2

1. Procedure . This day of testing is nearly identical to previous
day, except that it starts with a “probe trial,” and the escape
platform then placed in a different location for the remainder
of the test day. During the probe trial, animals are allowed to
swim freely for 1 min with no escape platform in the pool.
After all of the animals have had their probe trial, the escape
platform is placed into the pool in its new location and the fi ve
blocks of two trials begin as on the previous day.
2. Variables measured . The addition of the probe trial adds two
more variables specifi c to the probe trial—number of entries
into the former escape platform's location and percent of the
trial spent in the platform's quadrant.