Department of Neuroscience and the Howard Hughes Medical Institute, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA.
Nature. 2011 Apr 14;472(7342):213-6. doi: 10.1038/nature09868. Epub 2011 Mar 30.
Sensory information is transmitted to the brain where it must be processed to translate stimulus features into appropriate behavioural output. In the olfactory system, distributed neural activity in the nose is converted into a segregated map in the olfactory bulb. Here we investigate how this ordered representation is transformed in higher olfactory centres in mice. We have developed a tracing strategy to define the neural circuits that convey information from individual glomeruli in the olfactory bulb to the piriform cortex and the cortical amygdala. The spatial order in the bulb is discarded in the piriform cortex; axons from individual glomeruli project diffusely to the piriform without apparent spatial preference. In the cortical amygdala, we observe broad patches of projections that are spatially stereotyped for individual glomeruli. These projections to the amygdala are overlapping and afford the opportunity for spatially localized integration of information from multiple glomeruli. The identification of a distributive pattern of projections to the piriform and stereotyped projections to the amygdala provides an anatomical context for the generation of learned and innate behaviours.
感觉信息被传送到大脑，在那里必须对其进行处理，将刺激特征转化为适当的行为输出。在嗅觉系统中，分布在鼻子中的神经活动被转化为嗅球中的分离图谱。在这里，我们研究了这种有序的表示在小鼠的更高嗅觉中心是如何转化的。我们开发了一种示踪策略来定义从嗅球中的单个嗅小球传递信息的神经回路到梨状皮层和皮质杏仁核。在梨状皮层中，小球中的空间顺序被丢弃;来自单个嗅小球的轴突弥散投射到梨状皮层，没有明显的空间偏好。在皮质杏仁核中，我们观察到广泛的投射斑块，这些斑块对于单个嗅小球具有空间定型。这些到杏仁核的投射是重叠的，并为来自多个嗅小球的信息的空间局部化整合提供了机会。向梨状皮层的弥散投射模式和向杏仁核的定型投射的识别为学习和先天行为的产生提供了一个解剖学背景。
