Yu Xin, Wadghiri Youssef Zaim, Sanes Dan H, Turnbull Daniel H
Skirball Institute of Biomolecular Medicine, New York University School of Medicine, 540 First Avenue, New York, NY 10016, USA.
Nat Neurosci. 2005 Jul;8(7):961-8. doi: 10.1038/nn1477.
There are currently no noninvasive imaging methods available for auditory brain mapping in mice, despite the increasing use of genetically engineered mice to study auditory brain development and hearing loss. We developed a manganese-enhanced MRI (MEMRI) method to map regions of accumulated sound-evoked activity in awake, normally behaving mice. To demonstrate its utility for high-resolution (100-microm) brain mapping, we used MEMRI to show the tonotopic organization of the mouse inferior colliculus. To test its efficacy in an experimental setting, we acquired data from mice experiencing unilateral conductive hearing loss at different ages. Larger and persistent changes in auditory brainstem activity resulted when hearing loss occurred before the onset of hearing, showing that early hearing loss biases the response toward the functional ear. Thus, MEMRI provides a sensitive and effective method for mapping the mouse auditory brainstem and has great potential for a range of functional neuroimaging studies in normal and mutant mice.
尽管越来越多地使用基因工程小鼠来研究听觉脑发育和听力损失，但目前尚无用于小鼠听觉脑图谱绘制的非侵入性成像方法。我们开发了一种锰增强磁共振成像（MEMRI）方法，用于在清醒、行为正常的小鼠中绘制累积的声音诱发活动区域。为了证明其在高分辨率（100微米）脑图谱绘制中的效用，我们使用MEMRI展示了小鼠下丘的音频拓扑组织。为了在实验环境中测试其功效，我们从不同年龄经历单侧传导性听力损失的小鼠获取数据。当听力损失发生在听力开始之前时，听觉脑干活动出现更大且持续的变化，表明早期听力损失使反应偏向于功能正常的耳朵。因此，MEMRI为绘制小鼠听觉脑干提供了一种灵敏且有效的方法，在正常和突变小鼠的一系列功能神经成像研究中具有巨大潜力。
