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A three-dimensional virtual mouse generates synthetic training data for behavioral analysis


We developed a three-dimensional (3D) synthetic animated mouse based on computed tomography scans that is actuated using animation and semirandom, joint-constrained movements to generate synthetic behavioral data with ground-truth label locations. Image-domain translation produced realistic synthetic videos used to train two-dimensional (2D) and 3D pose estimation models with accuracy similar to typical manual training datasets. The outputs from the 3D model-based pose estimation yielded better definition of behavioral clusters than 2D videos and may facilitate automated ethological classification.

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Fig. 1: A realistic 3D mouse model suitable for generating labels for machine learning.
Fig. 2: Image-domain translation makes realistic videos of animated mouse models.

Data availability

All data and raw behavioral video images are available online at Open Science Framework: (ref. 2). Source data for Fig. 2 and Supplementary Figs. 13 are provided with this paper.

Code availability

All code and models are available on public repositories: (ref. 13) and (ref. 2); see workflow document for an overview of software steps. Code (KID score, U-GAT-IT, pose lifting and clustering) is set up for reproducible runs via a capsule on Code Ocean23.


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This work was supported by a Canadian Institutes of Health Research (CIHR) FDN-143209, NIH R21, a Fondation Leducq grant, Brain Canada for the Canadian Neurophotonics Platform and a Canadian Partnership for Stroke Recovery Catalyst grant to T.H.M. H.R. is supported by grants from Natural Sciences and Engineering Research Council of Canada (NSERC). D.X. was supported in part by funding provided by Brain Canada, in partnership with Health Canada, for the Canadian Open Neuroscience Platform initiative. This work was supported by computational resources made available through the NeuroImaging and NeuroComputation Centre at the Djavad Mowafaghian Centre for Brain Health (RRID SCR_019086). N.L.F. is supported by an NSERC Discovery Grant. Micro-CT imaging was performed at the UBC Centre for High-Throughput Phenogenomics, a facility supported by the Canada Foundation for Innovation, British Columbia Knowledge Development Foundation and the UBC Faculty of Dentistry. We thank E. Koch and L. Raymond of the UBC Djavad Mowafaghian Centre for Brain Health for the mouse open field video.

Author information

Authors and Affiliations



L.A.B., T.H.M., J.M.L. and D.X. developed the synthetic mouse concept. L.A.B. generated the mouse model and all main figure animations. C.D. made supplemental models. L.A.B., T.H.M., J.M.L. and D.X. wrote the manuscript. H.R. edited the manuscript and advised on algorithm selection and validation statistics. D.X. collected experimental data and performed data analysis. H.H., L.A.B., D.X. and P.K.G. performed modeling and data analysis. N.L.F. collected the computed tomography scans and advised on model selection and resolution.

Corresponding author

Correspondence to Timothy H. Murphy.

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Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Methods thanks the anonymous reviewers for their contribution to the peer review of this work. Nina Vogt was the primary editor on this article and managed its editorial process and peer review in collaboration with the rest of the editorial team.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–3 and Table 1.

Reporting Summary

Supplementary Video 1

Synthetic data tutorial.

Supplementary Video 2

Mouse model.

Supplementary Video 3

Style transfer U-GAT-IT model (wheel).

Supplementary Video 4

Style transfer U-GAT-IT model (open field).

Supplementary Video 5

Style transfer U-GAT-IT model (Janelia pellet reaching).

Supplementary Video 6

Model gallery.

Supplementary Video 7

Water reaching and grooming scenes.

Supplementary Video 8

DLC 3D pose lifting.

Supplementary Data 1

Source data Supplementary Fig. 1.

Supplementary Data 2

Source data Supplementary Fig. 2.

Supplementary Data 3

Source data Supplementary Fig. 3.

Source data

Source Data Fig. 2

Statistical source data.

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Bolaños, L.A., Xiao, D., Ford, N.L. et al. A three-dimensional virtual mouse generates synthetic training data for behavioral analysis. Nat Methods 18, 378–381 (2021).

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