Experimental quantification of improvement during circadian wheel running in the Indian field mouse, Mus terricolor: Theoretical uses

We quantified motor learning during voluntary wheel-running activity in the Indian pygmy field mouse, Mus terricolor. Wheel running in naive adults was monitored using the Clocklab system. A group of mice having 15 days prior wheel-running experience served as the control. The daily maximum wheel activity for the naive group increased from 21 ± 7 counts/min to 62 ± 4 counts/min in 15 days. The experienced group exhibited 62 ± 1 counts/min throughout the experiment. A significant correlation between days of wheel running and natural log of the highest count/min existed in the experimental group, but not in the experienced group. Thus, improvement in wheel running follows a logarithmic learning curve. Several research applications for this quantification have been discussed. The most important outcome of this quantification is that it primes the mice for a study in which the retention period for this motor learning, i.e. the time taken to "forget" motor learning during wheel running will be elucidated.