The first person who, I think, really developed some kind of insight into what was going on in the brain was the great Spanish neuroanatomist, Santiago Ramón y Cajal, in the 19th century, who used microscopy and special stains that could selectively fill in or render in very high contrast the individual cells in the brain, in order to start to understand their morphologies.
Acho que a primeira pessoa que lançou alguma luz sobre o que ocorria dentro do cérebro foi o grande neuroanatomista espanhol Santiago Ramón y Cajal, no século XIX, que usou a microscopia e corantes especiais que podiam colorir seletivamente ou criar um alto contraste as células individuais dentro do cérebro, para começar a entender a sua morfologia.