This video is the first time scientists have ever been able to image the whole brain of a vertebrate creature in such a way that you can see individual cells and simultaneously how they're firing and behaving in real time. This is how the brain really, really works—and it's amazing.
The research, published in Nature Methods, explains how scientists from the Howard Hughes Medical Institute Janelia Farm Research Campus were able to use a technique called high-speed light sheet microscopy to image the activity of 80 percent of the neurons in the brain of a zebra fish larva. They were able to capture images once every 1.3 seconds—which, as Nature explains, is a speed approximate to neural activity patterns in the brain.
It remains to be seen, however, if the technique can realistically be extended for use in other creatures: the technology relies on light transmission, which is possible in zebra fish larva because they are, weirdly, transparent. Try stepping up to something like a mouse, and you're currently outta luck.
Fortunately, there's plenty to be learned about fundamental processes in the human brain from analyzing footage like this. And in the meantime, we can all revel in the fact that it's insanely cool. [Nature Methods via Nature]