THE FUSE

For hundreds of years, the central nervous system and the body have been assumed to be two distinct territories. The brain was regarded as the center of consciousness, thoughts, emotions, and decisions, and the body was seen as the executor of the brain's commands and the receiver of sensory information. The discovery of the blood-brain barrier by German physician Paul Ehrlich in the 19th century reinforced this belief. This barrier protects the brain from potentially harmful blood-derived compounds. However, to allow the entry of essential substances, such as amino acids and glucose, into the neural tissues of the central nervous system, the barrier contains several specific transport systems.