Editorial: Home cage-based phenotyping in rodents: innovation, standardization, reproducibility, and translational improvement, volume II

Behavioral neuroscience has relied for decades on test paradigms that remove animals from their home cage, place them in novel arenas, and record responses commonly only for a few minutes. The logic seems self-evident: controlled conditions produce controlled data. Yet, the assumption deserves scrutiny. Novel environments and handling procedures are stressors triggering neuroendocrine responses. Short observation windows sample only a fraction of the circadian cycle. Experimenter presence introduces variability that is difficult to standardize across laboratories and across experimenters within the same laboratory (; ). What we gain in experimental control we often pay for in external validity, ethological and ecological relevance, replicability and, ultimately, in translatability.