Research Center for Neurotechnology, Southern Federal University, Rostov-on-Don, 344090, Russia.
Advanced Research Foundation, Moscow, 121059, Russia.
J Comput Neurosci. 2023 Nov;51(4):433-444. doi: 10.1007/s10827-023-00858-8. Epub 2023 Aug 25.
The comparison of odor functional maps in rodents demonstrates a high degree of inter-individual variability in glomerular activity patterns. There are substantial methodological difficulties in the interindividual assessment of local permutations in the glomerular patterns, since the position of anatomical extracranial landmarks, as well as the size, shape and angular orientation of olfactory bulbs can vary significantly. A new method for defining anatomical coordinates of active glomeruli in the rat olfactory bulb has been developed. The method compares the interindividual odor functional maps and calculates probabilistic maps of glomerular activity with adjustment. This adjustment involves rotation, scaling and shift of the functional map relative to its expected position in probabilistic map, computed according to the anatomical coordinates. The calculation of the probabilistic map of the odorant-specific response compensates for potential anatoamical errors due to individual variability in olfactory bulb dimensions and angular orientation. We show its efficiency on real data from a large animal sample recorded by two-photon calcium imaging in dorsal surface of the rat olfactory bulb. The proposed method with probabilistic map calculation enables the spatial consistency of the effects of individual odorants in different rats to be assessed and allow stereotypical positions of odor-specific clusters in the glomerular layer of the olfactory bulb to be identified.
在啮齿动物中，气味功能图谱的比较表明，在肾小球活动模式方面存在高度的个体间可变性。由于解剖学颅外标志的位置以及嗅球的大小、形状和角向都可能有很大的变化，因此在个体间评估肾小球模式中的局部排列存在实质性的方法学困难。已经开发出一种用于定义大鼠嗅球中活跃肾小球的解剖坐标的新方法。该方法比较个体间的气味功能图谱，并计算经调整的肾小球活动概率图谱。这种调整包括根据计算出的解剖坐标，相对于概率图谱中预期位置对功能图谱进行旋转、缩放和移位。气味特异性反应的概率图谱的计算补偿了由于嗅球尺寸和角向的个体变异性而导致的潜在解剖学误差。我们在通过大鼠嗅球背表面的双光子钙成像记录的大型动物样本的真实数据上展示了其效率。该方法通过计算概率图谱，能够评估不同大鼠中个体气味剂的影响的空间一致性，并确定嗅球肾小球层中特定气味簇的典型位置。
