The goal of the present work is automation of the Morris water pool test [1, 2] that is one of the most adequate and frequently used behavioral methods for study of memory and cognition functions in animals models of neurodegenerative disorders. In our specific experiments, aimed at testing of performance of various neuroprotectors, white rats are placed in water in round black pool 1.8 m in diameter and must find an invisible platform using visible landmarks around. Thus, an original system for tracking of the animal's trajectories in time and their analysis was developed.

The system consists of video hardware and a computer program. The hardware was chosen so as to provide high resolution, sufficient tracking speed, capability to create a video archive and adjust the video path parameters for optimization of the tracking conditions. The software should provide fast and qualitative tracking, storing the results in the database and video archive and their behavioral analysis. The detection and tracking of the object on a water surface is rather difficult due to multiple flashes (reflection) from the water. The construction of the unit and a special algorithm of processing of the image make it possible to solve this problem successfully, so the tracking process is practically insensitive to illumination and never crashes. The program automatically detects borders of the pool and other analyzed zones taking into account perspective and geometric distortions. Each track is automatically recorded on videotape during the experiment. All information about the experiment including the track position on the videotape is stored in the specially developed database and can be played back or repeatedly digitized (if required). A "streaming" mode of the experiment where tracking is started automatically at appearance of an animal in the pool and stopped at certain conditions is available in our system as well being very convenient for tests of a large number of animals.

Single tracks or experiments or any of their combinations can be analyzed using our software. A primary statistical analysis of the data obtained can be carried out directly in the program. The data can be exported into other programs such as Microsoft Excel, Statistica, etc. Currently the program is designated for tracking and analysis of animal behavior in a round pool, about 10 parameters being analyzed. However, it is object-oriented, so it can be easily modified for arbitrary pools and mazes of different shape and we can introduce any desirable criteria. The program operates under Windows 9x/NT/2000 and has a user-friendly interface. It has a comprehensive help system and detailed documentation. We will continue development of this software.

References

1. Morris, R.G.M.; Garrud, P.; Rawlins, J.N.P.; O'Keefe, J. (1982). Place navigation impaired in rats with hippocampal lesions. Nature, 297, 681-683.
2. Steele, R.J.; Morris, R.G.M. (1999). Delay-dependent impairment of a matching-to-place task with chronic and intrahippocampal infusion of the NMDA-antagonist D-AP5. Hippocampus, 9, 118-136.

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