ABSTRACT
Abstract-The model of the rotating beam was used to analyse detailed patterns of locomotor behaviour in anxious and non-anxious strains of mice. Comparisons involved the non-anxious B6D2F1 strain, the anxious ABPLe strain and the DBA/2J strain vulnerable to stressors. Detailed analysis was made of several parameters, both postural (height of the trunk, tail angle, number of imbalances and falls and head movements) and kinetic (mean speed on the beam, distance covered for large and small movements, plus time spent in no-motion episodes). The findings provided evidence of numerous differences between the strains: DBA/2J mice were moderately sensitive to the task and ABPLe subjects were extremely reactive. Signs of increased anxiety included a reduction in the tail angle, an increase in the number of imbalances, falls and head movements, a decrease in the mean speed and distance covered in large movements, and an increase in the number of no-motion episodes, as well as time spent and distance covered with small movements. All these data validate the use of the model to study the relationship between anxiety and balance control.
