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Neural Simulation Tool by the NEST Initiative

Scientific area

Large-scale simulations of biological neuronal networks.

Short description

The Neural Simulation Tool (NEST) is a simulator for spiking neural network models that focusses on the level of resolution of neurons and synapses. The identical code runs on systems ranging from laptops to supercomputers such as BlueGene/Q providing neuroscientists with a general exploration tool. NEST includes over 25 neuron and 10 synapse models which are solved by exact integration if possible and by numerical solvers else. It uses a hybrid parallelization scheme to perform the computations of the neuron and synapse dynamics and employs data structures suitable for brain-scale network simulations on peta-scale computers. The present weak scaling performance enables NEST to exploit the full memory of JUQUEEN to simulate 0.57 billion neurons connected via 6.4 trillion synapses. The largest simulation to date has been carried out on the K computer in Kobe representing 1.73 billion neurons with 10.4 trillion synapses commanding more than a peta byte of main memory.


  • 458,752 cores on BlueGene/Q (JUQUEEN)
  • 663,552 cores on SPARC64 VIIIfx (K computer)

Programming language and model

  • C++
  • MPI, OpenMP

Tested on platforms

  • BlueGene/Q
  • SPARC64 VIIIfx
  • x86

Application developers and contact

  • The NEST Initiative
  • Institute of Neuroscience and Medicine (INM-6),
    Computational and Systems Neuroscience
    & Institute for Advanced Simulation (IAS-6),
    Theoretical Neuroscience
    Forschungszentrum Jülich GmbH
    52425 Jülich