The Korean research team has developed a new method that uses magnetic resonance imaging (MRI) to non invasively track the propagation of brain signals on a millisecond time scale. The latest research published in the journal Science is expected to bring revolutionary breakthroughs to understanding the brain. Blood oxygen level dependent functional magnetic resonance imaging (fMRI) is used to obtain brain images of living people. This technology is not to directly observe the activity of neurons, but to track the changes of blood flow in the brain through an indicator, that is, blood oxygen level dependent effect. In practice, usually within a few seconds, fMRI depending on blood oxygen level will produce multiple images over time. In this new study, the researchers did not use any new equipment, but just modified the way of MRI brain scanning. This new technology is called Direct Neuron Activity Imaging (DIANA). Its working principle is to transform the traditional MRI machine to generate a series of local images at the millisecond level at a faster speed. This speed is equivalent to the speed of thinking. Neural signals are transmitted in milliseconds, and the whole cognitive, decision-making and other activities only take 0.1 seconds. Then, the researchers spliced these local images together to obtain a complete view of the brain cross-section at each time point. To see if they could identify any signals of brain activity in this way, the researchers put anesthetized mice into an MRI scanner and then tapped the whisker pads on their faces with an electric current. They found that, about 25 milliseconds after the shock, the image generated by their technology recorded a certain signal in the somatosensory cortex (the part of the brain of the mouse that senses beard stimulation). Further exploration shows that the DIANA signal actually moves over time. It appears in the brain area called thalamus about 10 milliseconds after hitting the beard pad, moves to one part of the somatosensory cortex about 25 milliseconds, and then appears in another part of the somatosensory cortex several milliseconds later. By using invasive techniques such as electrophysiology and photogenetics to measure the same brain region, the research team showed that the DIANA signal is actually tracking the response of neuron activity to beard stimulation. So far, this new technology has only been tested on mice, but researchers have called it a "game changer", which indicates that it may change the way scientists study the brain and may lead to a new understanding of how the brain works. Functional magnetic resonance imaging (fMRI) of editor in chief circle has revolutionized human understanding of the brain, but its spatial and temporal resolution still needs to be improved to reveal the secrets of brain neural function. The solution of the research team is to take a cross-sectional image of a specific brain region every few milliseconds, and then splice the local images together. The feasibility of this method has been verified in mouse experiments, tracking the response of neuronal activity to stimulation. In the future, it has the potential to be applied to the study of human brain. This is a revolutionary breakthrough, but it does not use any new instruments and equipment. The researchers improved the software to improve the detection time resolution of MRI to the millisecond level. (Outlook New Times)