Quantitative map of multiple auditory cortical regions with a stereotaxic fine-scale atlas of the mouse brain.

Hiroaki Tsukano,Kuniyuki Takahashi,Ryuichi Hishida,Katsuei Shibuki,Hirohide Takebayashi,Masao Horie

doi:10.1038/srep22315

Abstract

Optical imaging studies have recently revealed the presence of multiple auditory cortical regions in the mouse brain. We have previously demonstrated, using flavoprotein fluorescence imaging, at least six regions in the mouse auditory cortex, including the anterior auditory field (AAF), primary auditory cortex (AI), the secondary auditory field (AII), dorsoanterior field (DA), dorsomedial field (DM), and dorsoposterior field (DP). While multiple regions in the visual cortex and somatosensory cortex have been annotated and consolidated in recent brain atlases, the multiple auditory cortical regions have not yet been presented from a coronal view. In the current study, we obtained regional coordinates of the six auditory cortical regions of the C57BL/6 mouse brain and illustrated these regions on template coronal brain slices. These results should reinforce the existing mouse brain atlases and support future studies in the auditory cortex.

Highlights

Cortex map with at least 10 higher-order regions elucidated by physiological[9,10,12] and neurotracing studies[21] and a comprehensive body surface map of the somatosensory cortex have been portrayed
Anesthetized mice were fixed with the head rotated about 75° to bring the surface of the right auditory cortex to the microscope (Fig. 1b)
We presented 5- and 30-kHz tones to mice to generate tonotopic shifts in the anterior auditory field (AAF), auditory cortex (AI), and auditory field (AII), that were clearly distinguishable in these regions[4,5,16]

Summary

Introduction

Cortex map with at least 10 higher-order regions elucidated by physiological[9,10,12] and neurotracing studies[21] and a comprehensive body surface map of the somatosensory cortex have been portrayed. A fine auditory cortical map with multiple auditory regions is not currently available. We identified stereotaxic coordinates of the six auditory cortical regions of the C57BL/6 mouse by flavoprotein fluorescence imaging, and denoted their position in coronal brain slices. The mouse model is widely used in neuroscience research due to advantages in its applicability of various experimental tools, genetic tractability[22,23], and lissencephalic cortex[24]. The physiological identification of the auditory cortical regions will contribute to establishing a standard mouse brain database

Methods

Results

Conclusion