Left-Right Brain-Wide Asymmetry of Neuroanatomy in the Mouse Brain
Andrew Silberfeld,
James M. Roe,
Jacob Ellegood,
Jason P. Lerch,
Lily Qiu,
Yongsoo Kim,
Jong Gwan Lee,
William D. Hopkins,
Joanes Grandjean,
Yangming Ou,
Olivier Pourquié
Affiliations
Andrew Silberfeld
Department of Genetics, Harvard Medical School, Boston, MA, USA; Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA
James M. Roe
Center for Lifespan Changes in Brain and Cognition (LCBC), Department of Psychology, University of Oslo, Norway
Jacob Ellegood
Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital, Toronto, Ontario, Canada; Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
Jason P. Lerch
Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada; Department of Medical Biophysics, The University of Toronto, Toronto, ON, Canada; Department of Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON, Canada; Department of Preclinical Imaging, Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
Lily Qiu
Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada; Department of Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON, Canada
Yongsoo Kim
Department of Neural and Behavioral Sciences, College of Medicine, The Pennsylvania State University, Hershey, PA, USA
Jong Gwan Lee
Department of Genetics, Harvard Medical School, Boston, MA, USA; Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA
William D. Hopkins
Department of Comparative Medicine & Michale E Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, United States
Joanes Grandjean
Donders Institute for Brain, Behaviour, and Cognition, Nijmegen, Netherlands; Department for Medical Imaging, Radboud University Medical Center, PO Box 9101, Nijmegen, Netherlands
Yangming Ou
Boston Children's Hospital, Harvard Medical School, Harvard University, Boston, MA, USA
Olivier Pourquié
Department of Genetics, Harvard Medical School, Boston, MA, USA; Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA; Corresponding author.
Left-right asymmetry of the human brain is widespread through its anatomy and function. However, limited microscopic understanding of it exists, particularly for anatomical asymmetry where there are few well-established animal models. In humans, most brain regions show subtle, population-average regional asymmetries in thickness or surface area, alongside a macro-scale twisting called the cerebral petalia in which the right hemisphere protrudes past the left. Here, we ask whether neuroanatomical asymmetries can be observed in mice, leveraging 6 mouse neuroimaging cohorts from 5 different research groups (∼3,500 animals). We found an anterior-posterior pattern of volume asymmetry with anterior regions larger on the right and posterior regions larger on the left. This pattern appears driven by similar trends in surface area and positional asymmetries, with the results together indicating a small brain-wide twisting pattern, similar to the human cerebral petalia. Furthermore, the results show no apparent relationship to known functional asymmetries in mice, emphasizing the complexity of the structure-function relationship in brain asymmetry. Our results recapitulate and extend previous patterns of asymmetry from two published studies as well as capture well-established, bilateral male-female differences in the mouse brain as a positive control. By establishing a signature of anatomical brain asymmetry in mice, we aim to provide a foundation for future studies to probe the mechanistic underpinnings of brain asymmetry seen in humans – a feature of the brain with extremely limited understanding.
