File:Hearing sound localization circuits brainstem.jpg

Auditory Sound Localization Circuits in the Mammalian Brainstem

Schematic drawing of primary auditory sound localization circuits in the mammalian brainstem. For clarity, only the LSO or MSO are shown on each side.

Except for the auditory nerve, excitatory connections are shown in green and inhibitory connections are shown in red.

• AN - auditory nerve
• CN - cochlear nucleus
• HF - high frequency
• LF - low frequency

"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."

Original File name: Figure 1 Nihms-157821-f0001.jpg http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2780022/figure/F1/

Links: Hearing - Inner Ear Development

Reference

<pubmed>19471270</pubmed>

Licensee: Mark A Hill License Date: Apr 19, 2011 License Number: 2652771294696 Publication: Nature Neuroscience Title: Tonotopic reorganization of developing auditory brainstem circuits Type Of Use: post on the internet