the brain, but also in other neural structures. His research on spreading depression is still widely cited within the medical literature and the spreading depression, in the case of brain damage, can be reversed provided that the blood flow is restored quickly. However, there is no guarantee that the neurons may survive. History of Discovery The earliest origin of what has come to be known as spreading depression dates back to 1906, when Sir. William Richard Gowers, in a lecture on epilepsy, noted that “a peculiar spreading disturbance of the nerve structures is evident” and that lasts for several minutes, something that was confirmed and described by Aristides Leão in this way: While working on his PhD thesis at Harvard under the supervision of Hallowell Davis, Leão aimed to study "experimental "epilepsy". To perform the experiment he opened anesthetized rabbit skulls and placed a row of silver electrodes in contact with the cortical surface, with two serving for stimulation. However, instead of a seizure-like discharge, the stimulation was followed by a flattening of the brain waves in a kind of domino effect, which recovered in the same way. questions whether the ease with which this phenomenon can be caused did not cause other researchers to have observed it before Leão and dismissed it as an "annoying interruption of work" and goes on to say that this phenomenon intrigued him and became the main topic of Aristides' work, with his first article demonstrating the basic characteristics that have been confirmed by other researchers. In a following article he described how blood vessels behave during the event. The third article in focus by , made after Leão's return to Rio de Janeiro, deals with the slow voltage change that accompanies the phenomenon and the complete cerebral ischemia. Over the years other articles on the subject have been done, but it is still not understood why the spreading depression occurs. Awards The researcher is also remembered for his outstanding performance as president of the Brazilian Academy of Sciences between 1967 and 1981. His contribution to science earned him important scientific awards, such as the Einstein Award in 1961; the in 1973 and the Moinho Santista Award (now the Bunge Foundation Award), in 1974 and 1977. He also received posthumous tribute from the Brazilian Academy of Sciences, whose library today bears his name, being elected president emeritus of this institution on December 20, 1993.