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Tonotopic reorganization of developing auditory brainstem circuits

Nature Neuroscience volume 12, pages 711–717 (2009)Cite this article

Abstract

A fundamental organizing principle of auditory brain circuits is tonotopy, the orderly representation of the sound frequency to which neurons are most sensitive. Tonotopy arises from the coding of frequency along the cochlea and the topographic organization of auditory pathways. The mechanisms that underlie the establishment of tonotopy are poorly understood. In auditory brainstem pathways, topographic precision is present at very early stages in development, which may suggest that synaptic reorganization contributes little to the construction of precise tonotopic maps. Accumulating evidence from several brainstem nuclei, however, is now changing this view by demonstrating that developing auditory brainstem circuits undergo a marked degree of refinement on both a subcellular and circuit level.

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Figure 1: Schematic drawing of primary auditory sound localization circuits in the mammalian brainstem.
Figure 2: Cochleotopic refinement of auditory nerve projections in the developing anteroventral cochlear nucleus in neonatal cats.
Figure 3: Tonotopic refinement of an inhibitory map in the LSO.
Figure 4: Soma-dendritic and tonotopic refinement of inhibitory inputs to the gerbil MSO.

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Acknowledgements

We thank D. Goldring for editorial support and B. Cornell for insightful discussions. Our work was supported by grants from the National Institute on Deafness and Other Communication Disorders, the Alfred R. Sloan Foundation and the Pennsylvania Lions Hearing Research Foundation.

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Authors and Affiliations

  1. Departments of Otolaryngology, University of Pittsburgh School of Medicine, Eye and Ear Institute, Pittsburgh, Pennsylvania, USA

    Karl Kandler, Amanda Clause & Jihyun Noh

  2. Neurobiology, University of Pittsburgh School of Medicine, Eye and Ear Institute, Pittsburgh, Pennsylvania, USA

    Karl Kandler, Amanda Clause & Jihyun Noh

  3. Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon, University of Pittsburgh, Pittsburgh, Pennsylvania, USA

    Karl Kandler & Amanda Clause

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Correspondence to Karl Kandler.

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Kandler, K., Clause, A. & Noh, J. Tonotopic reorganization of developing auditory brainstem circuits. Nat Neurosci 12, 711–717 (2009). https://doi.org/10.1038/nn.2332

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