Aging-related behavioral defects in Caenorhabditis elegans

With the rapid development of quantitative behavioral analysis, locomotion behaviors can be examined and described in greater detail. However, behavioral structures underlying the dysfunctions and locomotor defects observed with aging remain poorly understood. Here, we recorded and analyzed worms' locomotion movement for both young and aged individuals. The results revealed distinct locomotion patterns between the two groups. Compared to the young worms, the aged individuals exhibited more disorganized forward locomotion, characterized by reduced periodicity and lower cycle stability. The time duration and frequency of backward locomotion did not differ significantly between the two groups, whereas turn behavior following reversals was significantly reduced. Moreover, the aged worms showed increased individual heterogeneity in the usage of behavioral repertoire with age. In summary, this study systematically characterizes the behavior defects of aged animals by quantifying changes in locomotor states, event transitions, and behavior organization.