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The human brain is the most complex and poorly understood biological structure known to man. Our human brain is relatively large for our body size and wrinkled in comparison to other animals' brains. Across species, brain size and wrinkle number is related to intelligence.

University of Copenhagen researchers have made an incredible discovery seeking to learn more about the  mammalian(哺乳动物的)  brain.  A  vital  enzyme,  a  special  material,  allows  brain  signals  to  be transmitted or transported. The enzyme is randomly turning on and off, even taking hours-long "breaks from work." These discoveries could have a significant impact on our understanding of the brain and the development of medicines. The discovery is featured on the cover of Nature.

Millions of neurons(神经元) are constantly communicating with one another, shaping thoughts and memories and allowing us to move our bodies at will. Neurotransmitters are transported from one neuron to another by a unique enzyme when two neurons meet to exchange a message.

This  process  is  necessary  for  neuronal  communication  as  well  as  the  survival  of all  complex organisms(extremely small living things). Until now, researchers all over the world assumed that these enzymes were constantly active, transmitting vital signals. However, this is not the case.

It is almost impossible to understand that the extremely critical process of loading neurotransmitters in containers is carried out by only one cell per container. Especially when we find that 40% of the time these cells are switched off.

Using a new method, researchers from the Department of Chemistry at the University of Copenhagen closely examined the enzyme and discovered that its activity switches on and off at random periods of time, contradicting our previous understanding.

"Contrary to popular belief, and unlike many other proteins, these enzymes could stop working for minutes to hours. Still, the brains of humans and other mammals are miraculously able to function," says Professor Dimitrios Stamou, who led the study from the research center at the University of Copenhagen's Department of Chemistry.

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