MCFBM: a behavioral analysis system enabling objective inference of songbirds' attention during social interactions

Understanding animal behavior is crucial in behavioral neuroscience, which aims to unravel the mechanism driving these behaviors. A milestone in this field is the analysis of behavioral reactions among animals engaging in social interactions. Although many studies have revealed the fundamental roles of social interaction in social learning, the behavioral aspects of these interactions remain poorly understood, largely due to the lack of tools for analyzing complex behaviors and the attention of subjects in naturalistic, free-moving conditions. Here, we introduce a high-precision system for behavior analysis in songbirds using a marker-based motion capture technique. This system accurately tracks the body location and head direction of freely moving finches and is applicable to multiple subjects during social interaction. With this system, we have quantitatively analyzed behaviors of zebra finches (Taeniopygia guttata) related to visual attention. Our analysis revealed variations in the use of right and left eyes, as well as the duration of sight, among the individuals presented. Further analysis and comparison of their behaviors during both virtual and live presentation identified the similarities and differences in their behavioral reactions. Additionally, we observed changes in their behavioral reactions during a conditioned learning paradigm. This system provides an efficient and easy-to-use tool for advanced behavioral analysis in songbirds, providing an objective method to infer their focus of attention.