动物实验,脑细胞 z-bo 2020-08-26 493

　　A new study by Science shows that neurons that fire at the same time are actually connected in series, which shows that the "three-pound computer" on your head is more adaptable than you think. In the latest issue of "Science", neuroscientists at Columbia University proved that when only one neuron in a neural network is stimulated, a group of neurons that can be activated after about a day will be activated. Their findings indicate that the reactivated neuron population may constitute a basic part of learning and memory, but further research is needed. Psychologist Donald Heb (Donald Heb) put forward the first hypothesis in the 1940s. The co-author of the study, Dr. Rafael Yuste, professor of neuroscience at Columbia University, said: "I always thought that the brain is immutable, but I saw this result and cried: "Well, the brain is completely plastic. We deal with plastic computers that are constantly learning and changing. "

　　Researchers use optogenetic technology to control and observe the brains of living mice, which has revolutionized the field of neuroscience in the past decade. We inject them into mice so that they can label specific brain cells with light-sensitive proteins, and when they enter the cells, researchers rely on them, just like switching programs on TV. Light can activate neurons remotely.

　　The mouse can move freely on the treadmill, but its head is always under the microscope. By firing a laser beam, researchers can stimulate a small group of cells in the visual cortex through the human brain, and then fire a second laser. When each neuron is excited, the calcium level increases when each neuron is excited.

　　, before providing us with optogenetics, scientists first opened up the brains of mice, then implanted electrodes into living tissues, and then punctured the tissues through electropuncture. We have to record the response through activation, but even the mouse brain tissue containing 100 million neurons is too dense for humans to be 1,000/1,000. With the advent of optogenetics, researchers can enter mice noninvasively The brain and more precise control of it. By manipulating specific areas of the mouse brain to restore the vision and hearing of deaf and blind mice, making ordinary mice more aggressive. This breakthrough research can reorganize cell clusters and is the culmination of more than ten years of research.

　　By studying tissue samples of mouse visual cortex, Yuste and colleagues discovered that they can be coordinated through a small network called the nervous system, which was published in the journal Nature in 2003.

　　One year later, they showed that the nervous system is stimulated by temporal and spatial patterns. With the continuous development of cell control and observation technology in the body, we have discovered that these nervous systems are still active even in the absence of stimulation, and they are used to inform the visual cortex. We have developed a mathematical algorithm for finding the human nervous system, which they developed while studying early tissue samples. We found that the nervous system of living animals can also be stimulated one after another in sequence. according to

　　Science's latest research, these neural networks can be artificially embedded and reconstructed like a tea-soaked Madeleine cake, so that the novelist Marcel Proust can remember childhood memories. I can. The combination of two-photon calcium imaging and two-photon excitation technology allows researchers to record the response of individual cells to light stimulation. Previous studies also focused on single cells and recorded the responses of single cells, but showed that many neurons in the brains of living animals can be fired at the same time, thus marking the so-called "neural microcircuits." No one does

　　Member of the American Institute of Data Science, Yuste said: The researchers said: "It's as difficult as sorting out three grains of sand on the beach."

　　, the brains of small mice don’t know the images of artificially activated neural networks. Currently, they are conducting behavioral studies on mice to try to prove this speculation. Luis Carrilloeid, the lead author of the study and a postdoctoral researcher at Columbia University, said: "

　　Dr. Daniel Habitt, a professor of psychiatry at Columbia University Medical Center, said he was not involved in the study. However, before applying optogenetics technology to the human body, major technical obstacles were discovered. This research is part of a $300 million brain localization effort, also known as the "American Brain Initiative." The predecessor of the project was based on early suggestions for cartography made by Yuste and his colleagues. Drosophila is a tool for brain activity and can be used in more complex mammals including humans.