Santiago Ramón y Cajal

Born in Spain in 1852, Santiago Ramón y Cajal trained as a doctor and went on to become the scientist most closely associated with the neuron doctrine, the idea that the nervous system is made up of separate nerve cells rather than one continuous network. Working with the microscope and refining staining methods, he produced remarkably detailed observations of brain tissue that reshaped biology and medicine.

He shared the 1906 Nobel Prize in Physiology or Medicine for his work on the structure of the nervous system. Alongside his scientific research, he was also a gifted illustrator, and his drawings of neurons are still admired for both their accuracy and beauty.

Cajal also wrote about science, creativity, and intellectual life in a way that still feels lively and personal. He died in 1934, but his work remains central to the history of neuroscience and to the story of how scientists first began to map the brain.