Center for Bioinformatics, National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University Beijing, China.
Front Neural Circuits. 2011 Feb 22;5:2. doi: 10.3389/fncir.2011.00002. eCollection 2011.
The ability to map functional connectivity is necessary for the study of the flow of activity in neuronal circuits. Optical imaging of calcium indicators, including FRET-based genetically encoded indicators and extrinsic dyes, is an important adjunct to electrophysiology and is widely used to visualize neuronal activity. However, techniques for mapping functional connectivities with calcium imaging data have been lacking. We present a procedure to compute reduced functional couplings between neuronal ensembles undergoing seizure activity from ratiometric calcium imaging data in three steps: (1) calculation of calcium concentrations and neuronal firing rates from ratiometric data; (2) identification of putative neuronal populations from spatio-temporal time-series of neural bursting activity; and then, (3) derivation of reduced connectivity matrices that represent neuronal population interactions. We apply our method to the larval zebrafish central nervous system undergoing chemoconvulsant-induced seizures. These seizures generate propagating, central nervous system-wide neural activity from which population connectivities may be calculated. This automatic functional connectivity mapping procedure provides a practical and user-independent means for summarizing the flow of activity between neuronal ensembles.
功能连接的映射能力对于研究神经元回路中活动的流动是必要的。钙指示剂的光学成像，包括基于 FRET 的基因编码指示剂和外源性染料，是电生理学的重要辅助手段，广泛用于可视化神经元活动。然而，用钙成像数据进行功能连接映射的技术一直缺乏。我们提出了一种从比率型钙成像数据中计算癫痫发作期间神经元集合的简化功能耦合的方法，该方法包括三个步骤：（1）从比率数据中计算钙浓度和神经元放电率；（2）从神经爆发活动的时空时间序列中识别潜在的神经元群体；然后，（3）得出表示神经元群体相互作用的简化连接矩阵。我们将我们的方法应用于经历化学惊厥诱导的癫痫发作的幼虫斑马鱼中枢神经系统。这些癫痫发作产生传播性的、中枢神经系统范围的神经活动，可以从中计算出群体连接。这种自动功能连接映射程序为总结神经元集合之间的活动流动提供了一种实用的、用户独立的方法。
