Working with zebrafish, U.S. scientists have achieved an excellent performance: recorded brain activity of the entire brain of the animal, thus creating the first “map” full brain of a living organism.
Last month, a team of scientists in Japan announced that it had managed to film the “thoughts” of a zebrafish – the animal’s brain activity while he was watching his prey. High-resolution images were limited to a particular area of the brain, optic tectum, a brain area associated with visual processes.
More recently, another scientific team, led by experts from the Howard Hughes Medical Institute, USA, has reached a new level: managed to film everything that happens in the brain of a fish. Presents search results were published in the scientific journal Nature Methods.
The subject was again this a young (fry), zebra fish, which have the great advantage of having a clear head, thereby allowing researchers to film the nerve activity in the brain.
Scientists initially used a technique similar to Japanese experts: fish used in experiments were genetically modified so that neurons at their synaptic activity to occur by an emission of light. (Synapses are the connections between neurons, which ensures the transmission of nerve impulses in the brain).
U.S. scientists have used a technique called “high-speed light-sheet microscopy,” known for some time, but had never used so efficiently and with results so impressive. Illuminating thin layers of only a few micrometers in the brain, at various levels, scientists have caught almost everything going on in the brain every 1.3 seconds.
Thus, they managed to record the activity of about 87% of brain zebrafish fry (a small part of the image is lost: either due to refraction of light, whether it was not visible because fisheye, which is interposed ray path light)
Approx. 92% of the total was recorded at a very high-resolution, up to the level of a single cell, which is, after scientists estimates, there has been at least 80% of the overall activity of the brain at the neuron level.
In the next decade, scientists hope to do such studies and the human brain. Obviously, the obstacles are high, making things harder than the zebrafish fry. Apart from having a transparent head, these creatures have the brain only about 100,000 neurons, while the human brain is about. 90 billion. And the technical obstacles plus the ethical.
However, the success of this research opens the way for an in-depth study of nerve activity in humans in the context of increasingly intense concern for scientists to decipher the secrets of higher nervous activity – the key to understanding how the human brain works.