Morpho-Functional Mapping of Cortical Networks in Brain Slice Preparations Using Paired Electrophysiological Recordings

  • Gabriele Radnikow
  • Robert Heinz Günter
  • Manuel Marx
  • Dirk Feldmeyer
Part of the Neuromethods book series (NM, volume 67)


The study of neuronal microcircuits with paired electrophysiological recordings from synaptically coupled neurons in brain slices has revealed a large variety of neuronal cell types with highly distinct and connection-specific characteristics of synaptic transmission. In combination with simultaneous biocytin fillings paired recordings permit correlated structural and functional analyses of pre- and post-synaptic neurons, including technically challenging approaches such as a quantal analysis of identified unitary synaptic connections. Here, we present the technical procedures for successful paired recordings, methods to obtain an optimal neuronal morphology, the working principle for neuronal reconstructions, and the basis and caveats in estimating neuronal connectivity from paired recording data. The paired recording technique will remain an important approach in the analysis of neuronal connectivity in the brain, in particular with respect to the finer details of synaptic transmission, since it allows the morphological and functional characterisation of both pre- and post-synaptic neuronal cell types which are not possible using other methods to study neuronal connectivity.

Key words

Neuronal connectivity Paired recordings Neuronal reconstructions Axonal domain Dendritic domain Innervation domain Synaptic contacts Structure–function correlations 



The authors would like to thank Werner Hucko for his excellent technical assistance and the Helmholtz Alliance for Systems Biology and the DFG Research Group ‘Barrel Cortex Function’ for financial support.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Gabriele Radnikow
    • 1
  • Robert Heinz Günter
    • 1
  • Manuel Marx
    • 1
  • Dirk Feldmeyer
    • 1
    • 2
  1. 1.Institute for Neuroscience and MedicineINM-2, Research Centre JülichJülichGermany
  2. 2.Department of Psychiatry, Psychotherapy and PsychosomaticsRWTH Aachen UniversityAachenGermany

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