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From the connectome to brain function

In this Historical Perspective, we ask what information is needed beyond connectivity diagrams to understand the function of nervous systems. Informed by invertebrate circuits whose connectivities are known, we highlight the importance of neuronal dynamics and neuromodulation, and the existence of parallel circuits. The vertebrate retina has these features in common with invertebrate circuits, suggesting that they are general across animals. Comparisons across these systems suggest approaches to study the functional organization of large circuits based on existing knowledge of small circuits.

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Figure 1: Connectivity of two well-studied invertebrate circuits.
Figure 2: C. elegans neurons essential for avoidance of light touch.
Figure 3: Similar changes in circuit dynamics can arise from three entirely different circuit mechanisms.
Figure 4: Two views of a multifunctional C. elegans circuit.
Figure 5: Changing either intrinsic neuronal properties or synaptic properties can alter network function.


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We thank M. Meister for sharing his knowledge of the retina. C.I.B. is funded by the Howard Hughes Medical Institute. Research in the Marder laboratory relevant to this piece is funded by the US National Institutes of Health (NS17813, NS 81013 and MH46742).

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Correspondence to Cornelia I Bargmann.

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Bargmann, C., Marder, E. From the connectome to brain function. Nat Methods 10, 483–490 (2013).

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