journal article·2026-05-02Open access

Experimental Analysis of Animal Behavior for Biomedical Applications

Florin Rotaru, Silviu-Ioan Bejinariu, Hariton-Nicolae Costin, Ramona Luca, Mihaela Luca, Cristina Diana Nita, Diana Costin, Bogdan-Ionel Tamba, Ivona Costachescu, Gabriela-Dumitrita Stanciu, Gabriela-Gladiola Petroiu

Applied Sciences· Volume 16· Issue 9

Abstract

This study addresses the problem of robust video-based tracking of laboratory rats in open-field and Y-maze experiments under challenging acquisition conditions, including non-uniform illumination, low contrast, and heterogeneous recording setups. Existing approaches based on classical image processing or deep learning often fail to maintain stable localization under such conditions or require large, annotated datasets. We propose a hybrid tracking framework that combines an improved motion–appearance voting mechanism with consistency-constrained optimization for open-field experiments, together with a comparative deep learning-based detection strategy for Y-maze analysis. The proposed method introduces (i) adaptive dual-threshold motion extraction, (ii) directionally constrained temporal validation, and (iii) a robustness-driven fusion of motion and appearance cues. Experimental results demonstrate that the proposed approach achieves reliable tracking with a maximum localization error below 10 pixels under severe illumination variations. In the Y-maze scenario, a comparative evaluation of multiple detectors (YOLOv5, YOLOv9, YOLO12, Faster R-CNN) highlights the trade-off between accuracy and inference time, with YOLOv9 providing the best balance. The main contribution consists of enabling robust behavioral quantification in low-quality experimental conditions using limited training data, bridging the gap between classical tracking robustness and deep learning flexibility.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Zebrafish Biomedical Research Applications · Video Surveillance and Tracking Methods · Human Pose and Action Recognition

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Institute of Computer Science, Romanian Academy, Iasi Branch, 2 T. Codrescu Str., 700481 Iasi, Romania

Faculty of Medicine, Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Str., 700115 Iasi, Romania

Advanced Research and Development Center for Experimental Medicine “Prof. Ostin C. Mungiu”, Grigore T. Popa University of Medicine and Pharmacy, 9-13 Mihail Kogalniceanu Str., 700454 Iasi, Romania

Faculty of Medical Bioengineering, Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Str., 700115 Iasi, Romania

References (37)

Show source-provided references
1. Brain development in rodents and humans: Identifying benchmarks of maturation and vulnerability to injury across species10.1016/j.pneurobio.2013.04.001 ↗
2. A review of behavioral methods for the evaluation of cognitive performance in animal models: Current techniques and links to human cognition10.1016/j.physbeh.2021.113652 ↗
3. Stress, behavioral arousal, and open field activity—A reexamination of emotionality in the rat10.1016/0149-7634(79)90012-5 ↗
4. Behavior features of rats in the “Open field” test under the influence of kisspeptin-10
5. Inter-individual differences in laboratory rats as revealed by three behavioural tasks10.1038/s41598-022-13288-w ↗
6. Chronic stress impairs rat spatial memory on the Y maze, and this effect is blocked by tianeptine pretreatment
7. An automated Y-maze based on a reduced instruction set computer (RISC) microcontroller for the assessment of continuous spontaneous alternation in rats10.3758/s13428-015-0674-0 ↗
8. Use of the Open Field Maze to measure locomotor and anxiety-like behavior in mice
9. Behavioral tests in rodent models of stroke10.1016/j.hest.2020.09.001 ↗
10. Assessing Spatial Working Memory Using the Spontaneous Alternation Y-maze Test in Aged Male Mice10.21769/BioProtoc.3162 ↗
11. Quantifying free behaviour in an open field using k-motif approach10.1038/s41598-019-56482-z ↗
12. MATSAP: An automated analysis of stretch-attend posture in rodent behavioral experiments10.1038/srep31286 ↗
13. TrAQ: A novel versatile semi-automated, two-dimensional motor behavioural tracking software10.1016/j.softx.2025.102138 ↗
14. RpiBeh offers a versatile open-source solution for rodent behavior tracking and closed loop interventions10.1038/s41598-025-14693-7 ↗
15. A deep learning-based approach for real-time rodent detection and behaviour classification10.1007/s11042-022-12664-y ↗
16. Applying Machine Learning to Determine the Behavioral Characteristics of Rodents with Traumatic Brain Injury in an Eight-arm Maze
17. Enhancing keypoint detection in Y-Maze behavior test automation: Introducing stadium heatmap and squared adaptive wing loss10.1007/s11042-024-20286-9 ↗
18. Computational modeling of animal behavior in T-mazes: Insights from machine learning10.1016/j.ecoinf.2024.102639 ↗
19. A quantitative analysis on spontaneous alternation behaviors on a Y-maze reveals adverse effects of acute social isolation on spatial working memory10.1038/s41598-023-41996-4 ↗
20. DeepLabCut: Markerless pose estimation of user-defined body parts with deep learning10.1038/s41593-018-0209-y ↗
21. Animal behavior analysis methods using deep learning: A survey10.1016/j.eswa.2025.128330 ↗
22. Rotaru, F., Costin, H., Bejinariu, S.-I., Luca, M., Luca, R., Nita, C.D., Tamba, B.-I., Szilagyi, A., and Stanciu, G.-D. (2024, January 27–28). Laboratory Rat Tracking Methods in Biomedical Experiments. Proceedings of the IEEE 16th International Conference on Electronics, Computers and Artificial Intelligence (ECAI), Iasi, Romania.10.1109/ECAI61503.2024.10607570 ↗
23. Bejinariu, S.-I., Rotaru, F., Costin, H., Luca, R., Nita, C.-D., Luca, M., Tamba, B.-I., Costachescu, I., and Stanciu, G.-D. (2025, January 17–18). Captive Animals Automatic Behavior Analysis. Proceedings of the International Symposium on Signals, Circuits and Systems (ISSCS), Iasi, Romania.10.1109/ISSCS66034.2025.11105676 ↗
24. Rotaru, F., Bejinariu, S.-I., Costin, H., Luca, M., Luca, R., Nita, C.-D., Costin, D., Tamba, B.-I., Costachescu, I., and Stanciu, G.-D. (2025, January 13–14). Animal Behavior Analysis in Biomedical Experiments. Proceedings of the International Conference on e-Health and Bioengineering (EHB), Iasi, Romania.
25. Ultralytics YOLO Docs (2026, February 02). Ultralytics YOLOv5. Available online: https://docs.ultralytics.com/models/yolov5/.
26. Redmon, J., Divvala, S., Girshick, R., and Farhadi, A. (2016, January 27–30). You Only Look Once: Unified, Real-Time Object Detection. Proceedings of the 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR), Las Vegas, NV, USA.10.1109/CVPR.2016.91 ↗
27. Ultralytics YOLO Docs (2025, October 12). Ultralytics: YOLOv9: A Leap Forward in Object Detection Technology. Available online: https://docs.ultralytics.com/models/yolov9/.
28. Leonardis, A., Ricci, E., Roth, S., Russakovsky, O., Sattler, T., and Varol, G. (2025). YOLOv9: Learning What You Want to Learn Using Programmable Gradient Information. Computer Vision—ECCV 2024. Lecture Notes in Computer Science, Springer.10.1007/978-3-031-73030-6 ↗
29. Ultralytics YOLO Docs (2026, February 02). YOLO12: Attention-Centric Object Detection. Available online: https://docs.ultralytics.com/models/yolo12/.
30. An efficient YOLOv12-based framework for detecting extremely small-scale objects10.1038/s41598-025-31803-7 ↗
31. Faster R-CNN: Towards Real-Time Object Detection with Region Proposal Networks10.1109/TPAMI.2016.2577031 ↗
32. Padilla, R., Passos, W.L., Dias, T.L.B., Netto, S.L., and da Silva, E.A.B. (2021). A Comparative Analysis of Object Detection Metrics with a Companion Open-Source Toolkit. Electronics, 10.10.3390/electronics10030279 ↗
33. Evaluating multiple object tracking performance: The CLEAR MOT metrics10.1155/2008/246309 ↗
34. Pellegrini, S., Ess, A., Schindler, K., and van Gool, L. (October, January 27). You’ll never walk alone: Modeling social behavior for multi-target tracking. Proceedings of the 2009 IEEE 12th International Conference on Computer Vision, Kyoto, Japan.10.1109/ICCV.2009.5459260 ↗
35. A systematic analysis of performance measures for classification tasks10.1016/j.ipm.2009.03.002 ↗
36. Jocher, G. (2026, February 02). YOLOv5 by Ultralytics. Available online: https://github.com/ultralytics/yolov5.
37. Wong, K.-Y. (2025, April 16). YOLOv9. Available online: https://github.com/WongKinYiu/yolov9.