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Neuroscience is a field of the biological sciences, which is ever changing in its technologies and advances. It is also one of the less understood biological systems. This owes itself to the fact that it is one of the most complex systems: unlike some computers which do one operation at a time, the nervous system works in parallel meaning that many operations occur at the same time. Only more recently, understanding has developed through the power of computation. The following page looks into the history of neuroscience, from the Egyptians to the modern day.

Recorded human understanding of the brain dates back to the Egyptians. They drilled into skulls in order to cure mental disorders.

However, for many centuries, the heart was thought to be the organ of intelligence, the entity which makes humans human.

This idea was later challenged by Hippocrates. He argued that it was the brain and not the heart which was designed for sensation and intelligence. He investigated epilepsy, for example, and saw how this was a disturbance of the brain.

On the other hand, Aristotle maintained that the heart was the centre of intelligence. In his view, the brain was simply an organ present to keep the blood cool.

This view changed when the Roman physician Galen, who worked with gladiators, saw in his patients that damage to the brain caused a loss in certain mental facilities.

In 1596 Descartes argued that nerves contained fluids, or "animal spirits," which are responsible for the flow of sensory and motor information in the body.

From the beginning of the 18th century, or the Age of Enlightenment, a period in which science progressed significantly, it was discovered that the nervous system was powered electrically. For example, Galvani, an Italian physician, saw how muscles and neurons were triggered by electronic impulses.

Gall and Spurzheim's divided brain

In the late 18th century, Franz Joseph Gall and Johann Spurzheim, both German neuroscientists, were able to divide the brain into 35 separate parts and functions. These ranged from concrete concepts like language and color to more abstract ones like hope or self-esteem.

At around the same time Johannes Pukinje was the first person to be able to describe a nerve cell

A significant turn in the history of neuroscience was seen with the invention of the microscope which developed the science further. For example, in the 1890s, Camilo Golgi, an Italian physician, used a staining procedure with silver chromate salt which showed the structure of neurons under a microscope.

British neurologist John Hughlings Jackson saw how epilepsy and the brain were connected using clinical observation. He also saw how brain damage caused speech loss, thus linking linguistic ability and mental facilities.

Also in the 19th century, French physician Paul Broca looked at how certain parts of the brain performed a certain function. For example, by looking at how a stroke victim could understand language but not speak it, he eventually concluded that the left frontal lobe was responsible for speech.

This kind of work was also seen in Carl Wernicke, a German physician, who investigated brain and speech/language

Throughout the history more and more detailed understanding was developed. For instance, Santiago Ramón Y Cajal, a Spanish physician, proposed that neurons transmit information only in one direction, which is from the dendrite to the axon.

Another area was researched by the American K. S. Lashley, who looked at where the memory lies by investigating rats.

Computational neuroscience has furthered the study of the brain dramatically. Eric L Schwartz, Professor of Cognitive and Neural Systems, Professor of Electrical and Computer Engineering, and Professor of Anatomy and Neurobiology at Boston University, first coined the term at the Systems Development Foundation conference in1985 in Carmel, California.

It is, then, a relatively new advance in the science. These developments driven by technology started largely in the 20th century. In 1943 Warren McCulloch and Walter Pitts investigated and illustrated how a neural network worked with electronic circuits.

With improvement in computers through the 50s and 60s, neurobiologists such as Frank Rosenblatt of Cornell were able to research neural vision in flies, for example. Funding for projects were limited, however, as initial funding was decreased when the research did no fulfill the hype it created initially.

Nonetheless, new models were continually being created. John Hopfield of Caltech wrote a paper which created new models, as well as new technologies which would use artificial intelligence for practical applications.

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 Ingo Wey, September 2008