Department of Physiology and Pharmacology, Cumming School of Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada.
Department of Physiology and Pharmacology, Cumming School of Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
eNeuro. 2024 Aug 7;11(8). doi: 10.1523/ENEURO.0450-23.2024. Print 2024 Aug.
It has long been assumed that activity patterns persist in neuronal circuits after they are first experienced, as part of the process of information processing and storage by the brain. However, these "reverberations" of current activity have not been directly observed on a single-neuron level in a mammalian system. Here we demonstrate that specific induced activity patterns are retained in mature cultured hippocampal neuronal networks. Neurons within the network are induced to fire at a single frequency or in a more complex pattern containing two distinct frequencies. After the stimulation was stopped, the subsequent neuronal activity of hundreds of neurons in the network was monitored. In the case of single-frequency stimulation, it was observed that many of the neurons continue to fire at the same frequency that they were stimulated to fire at. Using a recurrent neural network trained to detect specific, more complex patterns, we found that the multiple-frequency stimulation patterns were also retained within the neuronal network. Moreover, it appears that the component frequencies of the more complex patterns are stored in different populations of neurons and neuron subtypes.
长期以来，人们一直认为，在大脑进行信息处理和存储的过程中，神经元回路中的活动模式会在首次经历后持续存在。然而，这些电流活动的“回响”尚未在哺乳动物系统的单个神经元水平上被直接观察到。在这里，我们证明了在成熟的培养海马神经元网络中可以保留特定的诱导活动模式。网络中的神经元被诱导以单一频率或更复杂的模式（包含两个不同的频率）进行放电。刺激停止后，监测网络中数百个神经元的后续神经元活动。在单频刺激的情况下，观察到许多神经元继续以它们被刺激的相同频率放电。使用经过训练以检测特定、更复杂模式的递归神经网络，我们发现神经元网络中也保留了多频刺激模式。此外，似乎更复杂模式的组成频率被存储在不同的神经元群体和神经元亚型中。
