Regional, Layer, and Cell-Type-Specific Connectivity of the Mouse Default Mode Network.

Whitesell JD

Whitesell JD(1), Liska A(2), Coletta L(3), Hirokawa KE(4), Bohn P(4), Williford A(4), Groblewski PA(4), Graddis N(4), Kuan L(4), Knox JE(4), Ho A(4), Wakeman W(4), Nicovich PR(4), Nguyen TN(4), van Velthoven CTJ(4), Garren E(4), Fong O(4), Naeemi M(4), Henry AM(4), Dee N(4), Smith KA(4), Levi B(4), Feng D(4), Ng L(4), Tasic B(4), Zeng H(4), Mihalas S(4), Gozzi A(5), Harris JA(6).
Author information:
(1)Allen Institute for Brain Science, Seattle, WA 98109, USA. Electronic address: [Email]
(2)Functional Neuroimaging Laboratory, Istituto Italiano di Tecnologia, Center for Neuroscience and Cognitive Systems @ UniTn, 38068 Rovereto, Italy; DeepMind, London EC4A 3TW, UK.
(3)Functional Neuroimaging Laboratory, Istituto Italiano di Tecnologia, Center for Neuroscience and Cognitive Systems @ UniTn, 38068 Rovereto, Italy; Center for Mind/Brain Sciences
(CIMeC), University of Trento, 38068 Rovereto, Italy.
(4)Allen Institute for Brain Science, Seattle, WA 98109, USA.
(5)Functional Neuroimaging Laboratory, Istituto Italiano di Tecnologia, Center for Neuroscience and Cognitive Systems @ UniTn, 38068 Rovereto, Italy.
(6)Allen Institute for Brain Science, Seattle, WA 98109, USA. Electronic address: [Email]

https://dx.doi.org/10.1016/j.neuron.2020.11.011

The evolutionarily conserved default mode network (DMN) is a distributed set of brain regions coactivated during resting states that is vulnerable to brain disorders. How disease affects the DMN is unknown, but detailed anatomical descriptions could provide clues. Mice offer an opportunity to investigate structural connectivity of the DMN across spatial scales with cell-type resolution. We co-registered maps from functional magnetic resonance imaging and axonal tracing experiments into the 3D Allen mouse brain reference atlas. We find that the mouse DMN consists of preferentially interconnected cortical regions. As a population, DMN layer 2/3 (L2/3) neurons project almost exclusively to other DMN regions, whereas L5 neurons project in and out of the DMN. In the retrosplenial cortex, a core DMN region, we identify two L5 projection types differentiated by in- or out-DMN targets, laminar position, and gene expression. These results provide a multi-scale description of the anatomical correlates of the mouse DMN.