Computer analysis, using a digitizer, of ataxic mouse gait due to drugs

A simple objective method using the irregularity of the spacing of rats' footprints to determine drug-induced locomotor ataxia has been adapted for mice and for computer analysis, by means of a digitizer-based program. Results obtained by the usual manual method of measuring and analyzing the records are compared with results of the computerized method. The computer method improves speed, and perhaps accuracy, of measurement and analysis, especially with large numbers of records, although manual scoring gives satisfactory results and remains essential for unusual records. Inter-observer agreement of the computerized method was high, and there was good agreement between measurements and subjective ratings of ataxia. The use of footprints to measure ataxia, with or without computer aid, is recommended as a routine test in laboratory evaluation of psychoactive drugs. Other uses discussed include determining changes in different characteristics of gait such as step width and step length in animal and human subjects affected not only by drugs, but also by movement disorders such as Parkinsonism.