NIH BRAIN Initiative • $40M Project • 2023–2028

MouseConnects Complete Hippocampal Connectome

A synapse-level reconstruction of 10 mm³ of the mouse hippocampal formation – revolutionizing our understanding of memory circuits.

Revolutionary Scale & Impact

MouseConnects represents a quantum leap in connectomics, targeting the mouse hippocampal formation - the brain region essential for memory formation and spatial navigation. This project will generate the first complete synaptic wiring diagram of a mammalian memory circuit.

10 mm³
Brain Volume
50× larger than previous connectomes
4 nm
Resolution
nanometer resolution
>10 PB
Data Size
Unprecedented scale
7 Sites
Global Team
Leading institutions worldwide

Key Innovations

  • Novel mSEM-IBEAM Technology: Combines multibeam electron microscopy with ion beam milling
  • Distributed Imaging: Multiple sites working in parallel for unprecedented speed
  • AI-Powered Reconstruction: State-of-the-art machine learning for automated segmentation
  • Open Science: All data and tools freely available to the global research community

Scientific Questions Addressed

  • How do hippocampal circuits encode spatial information and episodic memories?
  • What are the detailed microcircuit motifs underlying grid and place cell function?
  • How do different cell types contribute to memory formation and retrieval?
  • What circuit principles enable the hippocampus to act as a cognitive map?

Cutting-Edge Technology Stack

🔬

mSEM-IBEAM Imaging

91-beam scanning electron microscopy combined with ion beam milling for automated blockface imaging at unprecedented scale.

  • Two imaging sites: Harvard & Princeton
  • Automated wafer handling
  • Real-time quality monitoring
☁️

Google Cloud Processing

Massive-scale data processing using Google's cloud infrastructure for alignment, segmentation, and analysis.

  • Flood-filling networks for neuron tracing
  • Automated synapse detection
  • Real-time collaborative proofreading
🧬

Multi-Modal Integration

Combining EM data with Patch-seq recordings, fMOST morphology, and transcriptomic cell typing.

  • 4,000+ Patch-seq recordings
  • Whole-brain fMOST reconstructions
  • Cross-modal cell type matching

World-Class Collaborative Team

🏛️ Harvard University

Jeff Lichtman, PI
Sample preparation and imaging expertise with decades of connectomics experience

🎓 Princeton University

Sebastian Seung & David Tank
mSEM imaging technology and deep learning algorithms for automated reconstruction

☁️ Google Research

Viren Jain
Cloud-scale processing infrastructure and machine learning segmentation algorithms

🧮 MIT

Ila Fiete
Circuit analysis, computational modeling, and theoretical frameworks for spatial coding

🧠 Allen Institute

Hongkui Zeng
Patch-seq recordings, transcriptomic cell typing, and multi-modal data integration

🔬 University of Cambridge

Gregory Jefferis
Data integration, analysis pipelines, and connectome interpretation methods

🚀 Johns Hopkins APL

William Gray-Roncal
Connectome quality assurance, community training, and data dissemination

🚧

Data Release Coming Soon

The MouseConnects dataset is currently in active development. Data release, interactive browsers, and analysis tools will be made available as the project progresses. Stay tuned for updates!