The Marquee Water Maze is an escape maze. It is circular pool with a clear Plexiglas circular wall. It was used to show that there’s no evidence for cognitive mapping in rats.

Centered inside the pool was a kind of marquee which divided the available space into an inner pool surrounded by a peripheral channel. It was a metallic cylinder with an interior painted uniformly white, open over 90 on all its height and surmounted by a cone-shaped opaque white plastic roof.

This marquee could be turned horizontally around its center so that the opening could be set at different orientations. The rats’ movements in the inner pool were monitored by means of a video camera set just above the top of the roof.

A white cylinder served as an escape platform. This hidden goal was located in the inner pool, 30 cm from the pool center.

Mazeengineers offers the Marquee Water Maze.

Price & Dimensions

Mouse

$ 1890

+S&H
  • Diameter of circular pool: 0.93m
  • Height of Plexiglas circular wall: 33.3cm.
  • Diameter of marquee: 0.79m
  • Height of marquee: 0.66m
  • Height of cone-shaped roof: 0.66m
  • Diameter of escape platform: 5.32cm
  • Height of escape platform: 11.9cm
  • Distance between escape platform and pool center: 19.9cm

Rat

$ 1990

+S&H
  • Diameter of circular pool: 1.40m
  • Height of Plexiglas circular wall: 50cm.
  • Diameter of marquee: 1.20m
  • Height of marquee: 1m
  • Height of cone-shaped roof: 1m
  • Diameter of escape platform: 8cm
  • Height of escape platform: 18cm
  • Distance between escape platform and pool center: 30cm

Documentation

Introduction

The Marquee Water Maze was developed by Benhamou (1996) to assess cognitive mapping abilities in rats. The Marquee Water Maze consists of a circular pool that has a rotatable marquee in the center. It allows the subjects to view only sections of the experimental room from inside it. Over the course of training, the subjects can view different parts of the room that serve as extra maze landmarks. The subjects are tasked with piecing together the extra-maze cues to create a reliable representation of the environment. Unlike the Morris water maze, which only allows local place navigation in rodents, the Marquee Water Maze can be used to observe global place navigation.

Rodents are fundamentally good swimmers; however, they prefer to stay on dry land. The Marquee Water Maze utilizes this aversiveness of water to motivate learning and memory of the hidden platform that serves as an escape. The complexity of the maze prevents the use of simple orientation mechanisms in solving the task since the opening orientation cannot be used as a reliable spatial cue. Additionally, the marquee prevents the subjects from perceiving landmarks from their current location and the goal location, which is reflective of the lack of overlap between current and memorized goal panorama in the natural environment. Apart from assessing cognitive processes in rodents, the Marquee Water Maze can also be used to evaluate age-related changes in rodents and the effects of diseases and disorders, brain lesions, and pharmacological manipulation on learning and memory behaviors.

Other apparatuses used to test behaviors in rodents include the Morris Water Y-Maze, the Radial Arm Water Maze, the Morris Water T-Maze, and the Morris Water Star Maze.

Apparatus and equipment

The apparatus consists of a circular pool 1.40 m in diameters with 50 cm high walls. The center of the pool contains a marquee made of a metallic cylinder 1.20 m in diameter, 1 m high, with a cone-shaped opaque white plastic roof (1 m high). The marquee divides the circular pool into an inner pool surrounded by a peripheral channel and can be turned horizontally around its center. The opening of the marquee can be set at different orientations. A removable escape platform made of a white cylinder (8 cm in diameter and 18 cm high) is present in the inner pool at 30 cm from the pool center.

Training protocol

Appropriately light the apparatus. A tracking and recording system such as the Noldus Ethovision XT can be used to assist with observations.

Habituation and Pre-training

Habituate the subject to the maze by placing a flat plastic annulus into the peripheral channel just above the water surface and placing the subject on this dry pathway. Allow the subject to familiarize itself with the apparatus for four sessions of 15 minutes a day for 2 days. During the first block of trials, prior to starting trials, raise the escape platform by a few centimeters. Place the subject on the escape platform for 30 seconds.

Following habituation, initiate pre-training trials by releasing the subject into the peripheral channel opposite the opening of the marquee. Block the left or right direction of the peripheral channel for the first few trials. Point the subject in the correct direction. Allow the subject to reach the platform after being released into the marquee in a maximum of 60 s. After the subject reaches the platform, allow it to stand on the platform for 10-15 s. If the subject does not find the platform, pick it up from the pool and place it directly on the platform. Position the opening of the marquee at a familiar orientation. Conduct trials for 3 days.

Marquee Water Maze test

Position the opening of the marquee at an unfamiliar orientation relative to that used in the pre-training. Release the subject into the peripheral channel and perform trials in the same manner as pre-training. After conducting three trials, return the subject to its cage. Rotate the opening of the marquee to a new position and position the platform to a new location. Release the subject into the peripheral channel and conduct the trial. Repeat trials as required with a new location of marquee entry and platform location.

Protocols may vary according to the investigation.

Evaluation of cognitive mapping in rats

Benhamou (1996) evaluated if rats possess cognitive mapping abilities using the Marquee Water Maze. Sixteen Long Evans hooded rats performed four blocks of four trials a day with familiar opening orientations as well as unfamiliar opening orientations. Searching pattern analysis and navigational parameters were assessed in the experiments.  In experiment 1, the rats were 12 weeks old, and training lasted for 8 days. It was observed that efficiency improved across trials with familiar opening orientations; however, efficiency decreased with unfamiliar opening orientations. Although the rat’s performance reached good levels during the final test with four familiar opening orientations, the navigational efficiency was very poor, and the rats searched for the platform at random. In experiment 2, when 5 opening orientations were used, similar results were obtained when the opening pattern was rotated by 180̊, and the platform was moved to a new location. In experiment 3, a large window was cut out of the marquee opposite the opening. The opening pattern orientation was the same as experiment 1, and the platform was moved to a new location. Results indicated that although efficiency was not great during the test trial, the rats searched for the platform near the correct location. Overall, results from the three experiments indicated no evidence for cognitive mapping in the rats.

Evaluation of path integration by swimming rats

Benhamou (1997) evaluated whether naive male Long Evans hooded rats could effectively use path integration to return to a starting point while swimming along a circular outward path. The experiment was conducted in a Marquee Water Maze with the marquee having 6 small openings at every 60°, that could be left open or closed. Additionally, efforts were made to eliminate the use of external landmarks in solving the task. Rats were initially placed on the escape platform in the inner pool placed behind one of the openings. They were then led through the opening into the peripheral channel. Once in the outer pool, the initial entry point was closed, forcing the subject to look for alternative routes. Following training with the openings in either anti-clockwise or clockwise manner, subjects were evaluated for their ability to utilize path integration to reach the escape platform. It was observed that the rats would move first to the correct location, or head directly to the adjacent opening. Overall, the results indicated that rats utilized path integration to update the memory of the platform location while swimming.

Data analysis

The following can be observed on the Marquee Water Maze:

  • Time required to reach the platform
  • Number of times the subject did not find the platform
  • Distance traveled to find the platform
  • Total distance traveled

Strengths and limitations

Strengths

The Marquee Water Maze allows investigation of spatial navigation memory in rodents. It consists of a rotating marquee that allows the subject to view different parts of the experimental room across trials. The marquee also allows different opening orientations to be used, which prevents the subjects from using the opening orientation as a reliable spatial cue. Rodents experience an increased motivation to escape and perform more rapidly using the Marquee Water Maze as compared to dry mazes. A major advantage of using the Marquee Water Maze is the absence of intra maze cues.

Limitations

Forced swimming may serve as an aversive stimulus and may affect task performance. Since the task is complex, learning may not occur rapidly. Training is highly important for task performance. Factors such as age, gender, and strain of the subjects may affect task performance. The exploratory drive of the subjects is necessary for the completion of the task. The presence of unintentional stimuli may affect the way the subject performs the task. Overtraining of subjects may result in muscle fatigue.

Summary

  • The Marquee Water Maze is used to study spatial learning and memory in rodents.
  • It consists of a circular pool that has a rotating marquee in the center that only allows subjects to view sections of the room within an experimental trial.
  • The walls of the room serve as extra-maze cues.
  • The Marquee Water Maze resembles the natural environment of rodents because there is an absence of overlap between the current panorama and memorized goal panorama.
  • The Marquee Water Maze allows the observation of global place navigation in rodents.

References

  1. Benhamou, S. (1996). No evidence for cognitive mapping in rats. Animal Behaviour52(1), 201-212.
  2. Benhamou, S. (1997). Path integration by swimming rats. Animal Behaviour, 54(2), 321–327. doi:10.1006/anbe.1996.0464