Figure 1 Water maze with rat on platform

The second maze in the study is the elevated plus maze. This consists of four platforms measuring 10cm by 50 cm, connected in the middle by a 10cm by 10 cm square, and built with opaque white acrylic plastic. Two opposing platforms have walls that are 40 cm high. The entire maze sits 60 cm off the ground. This maze is run in red light, which the rats perceive as darkness. The rats feel safe in the walled sections of the maze, and must overcome anxiety to venture into the open areas. By measuring the amount of time spent in each section of the maze, researchers can assess how exercise reduces levels of anxiety.

Figure 2 Elevated plus maze

Figure 3 Rat in elevated plus maze

The third maze used to evaluate the rat’s behavior is the Ettenberg runway. This maze contains a 15 cm by 155 cm hallway, with 25 cm square boxes at either end, all made of opaque white acrylic plastic. The rat begins in one box, and the time it spends to reach the other box is measured. Different stimuli are placed in the second box, and the time and speed it takes to reach the goal is used to assess the rat’s affinity for the stimulus. In this study, exercise is being explored as a possible reward.

Figure 4 Runway Maze

System

An optical data acquisition system was developed in this project to analyze movements of rats in the mazes. The researchers in the psychology department currently assess the rat movement using stopwatches to record time durations and by visually monitoring behavior. An automated system is desired to reduce human workload, provide a playback option, and record time, location, and velocity information in a repeatable fashion.

A Canon Optura xi video camera was purchased to record data in the mazes. A wide angle lens is used to capture the entire maze in one frame. Labview programs are used to record and analyze the images taken by the video camera.