Neuroscientists from the Francis Crick Institute have developed a new technology that has mapped the neural microchains of the brain, with a level of accuracy and detail many times greater than that provided by traditional methods. Note that traditional methods use special viruses or dyes, which limits the study area and allows the study of neural tissue only of the simplest organisms, such as drosophila flies and zebrafish.
In the brain, groups of neurons form quite complex neural circuits that allow the brain to process incoming information – all that we see, hear, and feel. Knowing how many neurons and other cells are involved in this process gives scientists a deeper understanding of the brain as a whole.
The researchers used nanoengineered electroporation microelectrodes (NEM) to make a highly accurate map of neural microchains. Using these electrodes, scientists investigated all 250 nerve cells, which are a separate functional group (olfactory bulb glomerulus) of the brain of the experimental rodent that processes olfactory sensations.
A series of tiny holes are created at the end of the microelectrode-pipette using specialized nano-tools. This makes it possible to obtain a more uniform distribution of electric current in an area with a radius of 50 micrometers, which on average corresponds to the size of a typical neuronal microchain. At the same time, the use of such microelectrodes – “paint sprayers” makes it possible to stain individual cells, causing minimal damage to the nerve cells themselves.
Using a microelectrode-pipette, scientists were able to stain absolutely all living cells that make up the microchain under study. “Since the brain consists of a set of “type components,” which are neuronal microchains of different configurations, we can learn quite a lot about how the brain works at the microscopic level by thoroughly studying each of the existing types of microchains,” the researchers write, “Now we have a tool that allows us to obtain a highly accurate map of each circuit, and with its help we can figure out how certain types of nerve cells participate in behavior formation and sensory processing.”
