The insular cortex (IC) plays key roles in emotional and regulatory brain functions and is affected across psychiatric diseases. However, the brain-wide connections of the mouse IC have not been comprehensively mapped. Here we traced the whole-brain inputs and outputs of the mouse IC across its rostro-caudal extent. We employed cell-type specific monosynaptic rabies virus tracings to characterize afferent connections onto either excitatory or inhibitory IC neurons, and adeno-associated viral tracings to label excitatory efferent axons. While the connectivity between the IC and other cortical regions was highly bidirectional, the IC connectivity with subcortical structures was often unidirectional, revealing prominent cortical-to-subcortical or subcortical-to-cortical pathways. The posterior and medial IC exhibited resembling connectivity patterns, while the anterior IC connectivity was distinct, suggesting two major functional compartments. Our results provide insights into the anatomical architecture of the mouse IC and thus a structural basis to guide investigations into its complex functions.
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided in Supplementary File 2.
- Caroline Weiand
- Nadine Gogolla
- Daniel August Gehrlach
- Alexandru A Hennrich
- Karl-Klaus Conzelmann
- Nadine Gogolla
- Thomas N Gaitanos
- Nadine Gogolla
- Alexandra S Klein
- Nadine Gogolla
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All animals were used in accordance with the regulations and under licenses obtained from the government of Upper Bavaria (Animal license AZ: 55.2-1-54-2532-56-2014).
- Kate M Wassum, University of California, Los Angeles, United States
© 2020, Gehrlach et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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