Measuring Behavior in the Home Cage: Study Design, Applications, Challenges, and Perspectives.

Area of Science:

• Behavioral Neuroscience
• Biomedical Research
• Animal Behavior Analysis

Background:

• The reproducibility crisis in biomedical research is exacerbated by confounding environmental factors and human interference in behavioral neuroscience.
• Automated home-cage monitoring systems offer a solution by reducing human interference and capturing natural behaviors.
• These systems enable prolonged, longitudinal recordings of spontaneous behavior for multi-scale analysis.

Purpose of the Study:

• To review the use of automated home-cage monitoring systems, specifically Noldus PhenoTyper and EthoVision XT, for extracting digital biomarkers.
• To compare home-cage testing with conventional out-of-cage tests, highlighting advantages like within-subject analysis and circadian rhythm assessment.
• To provide guidance on technical issues, data acquisition, analysis, and applications in neuropharmacology and disease models.

Main Methods:

• Utilized Noldus PhenoTyper home-cages and EthoVision XT video-tracking software for automated behavioral monitoring.
• Compared home-cage testing with traditional methods like the open field test.
• Discussed technical aspects including software fine-tuning, biotelemetry, and optogenetics integration.

Main Results:

• Automated home-cage systems provide digital biomarkers for motor, emotional, social, and cognitive behaviors.
• Advantages include reduced variability, enhanced within-subject analyses, and assessment of circadian/ultradian activity.
• The PhenoTyper system shows applications in neuropharmacology and models of neurodegenerative/neuropsychiatric illnesses.

Conclusions:

• Standardized home-cage monitoring platforms like PhenoTyper are crucial for addressing reproducibility issues in behavioral neuroscience.
• These systems facilitate the measurement of rodent behavior in more ethologically relevant scenarios.
• Future developments focus on automated behavior recognition, social tracking, animal-centered measures, and big data handling.