Paoli Marco, Antonacci Yuri, Albi Angela, Faes Luca, Haase Albrecht
Research Center of Animal Cognition, Center for Integrative Biology, CNRS, University of Toulouse, 31400 Toulouse, France.
Dipartimento di Ingegneria, Università di Palermo, 90128 Palermo, Italy.
Insects. 2023 Jun 9;14(6):539. doi: 10.3390/insects14060539.
Odorant processing presents multiple parallels across animal species, and insects became relevant models for the study of olfactory coding because of the tractability of the underlying neural circuits. Within the insect brain, odorants are received by olfactory sensory neurons and processed by the antennal lobe network. Such a network comprises multiple nodes, named glomeruli, that receive sensory information and are interconnected by local interneurons participating in shaping the neural representation of an odorant. The study of functional connectivity between the nodes of a sensory network in vivo is a challenging task that requires simultaneous recording from multiple nodes at high temporal resolutions. Here, we followed the calcium dynamics of antennal lobe glomeruli and applied Granger causality analysis to assess the functional connectivity among network nodes in the presence and absence of an odorous stimulus. This approach revealed the existence of causal connectivity links between antennal lobe glomeruli in the absence of olfactory stimulation, while at odor arrival, the connectivity network's density increased and became stimulus-specific. Thus, such an analytical approach may provide a new tool for the investigation of neural network plasticity in vivo.
气味处理在不同动物物种之间存在多个相似之处，由于其潜在神经回路易于处理，昆虫成为嗅觉编码研究的相关模型。在昆虫大脑中，气味由嗅觉感觉神经元接收，并由触角叶网络进行处理。这样的网络包含多个名为小球体的节点，它们接收感觉信息，并通过参与塑造气味神经表征的局部中间神经元相互连接。在体内研究感觉网络节点之间的功能连接是一项具有挑战性的任务，需要在高时间分辨率下同时从多个节点进行记录。在这里，我们追踪了触角叶小球体的钙动力学，并应用格兰杰因果分析来评估在有气味刺激和无气味刺激情况下网络节点之间的功能连接。这种方法揭示了在没有嗅觉刺激时触角叶小球体之间存在因果连接关系，而在气味到达时，连接网络的密度增加并变得具有刺激特异性。因此，这种分析方法可能为体内神经网络可塑性的研究提供一种新工具。
