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Santiago Ramón y Cajal b. 1852




When Santiago Ramón y Cajal was eleven, he famously spent a few days in jail for destroying his neighbor’s garden gate with a homemade cannon. Born in Northern Spain in 1852, he was an avid artist and gymnast who didn’t like being told what to do. Santiago’s rebellious personality got him kicked out of more than one school. When apprenticeships with a shoemaker and a barber didn’t work out, his father, a professor of anatomy, took him to the graveyard hoping to convince his son to pursue a medical degree. His plan succeeded and Santiago, fascinated by drawing the bones they found, went to study medicine at the university.


After graduating from college, Santiago became a medical officer in the Spanish Army and traveled to Cuba, where he contracted the mosquito-borne disease malaria and was infected with tuberculosis. When he’d recovered, he returned to Spain where he went to graduate school, married, and had twelve children. Much of his early scientific research was spent looking through a microscope, focused on cellular structure, inflammation, and the bacterium Vibrio cholerae, which causes the disease cholera.


In 1887, Santiago and his family moved to Barcelona where he learned to stain tissue samples with special dyes that made certain cells and their structures easier to see under a microscope. He improved the staining methods and used them to dye brain and nerve cells, illustrating what he observed using the skills he’d developed when he was young.


Santiago Cajal’s drawings expanded scientific understanding of nerve cells and the neural networks they form to communicate with one another. He demonstrated that the nervous system was made up of individual cellular units which were later named neurons. He also described growth cones on nerve cells, discovered fingerlike dendritic spikes, and correctly guessed that nerve cells receive messages on one end and send them through their axons to the opposite end. A new type of cell he discovered and described was eventually named the “interstitial cell of Cajal.”


In 1906, Santiago Ramón y Cajal and the Italian scientist Camillo Golgi were co-winners of the Nobel Prize for Biology in recognition of their work on the structure of the nervous system.


Neurology, the study of nerves and the brain, continues to be an important field of research today, as scientists work to cure disease and understand how the human nervous system functions.



Santiago Ramón y Cajal correctly guessed that nerve cells receive messages and send them from one end to the other via the axon. Make your own collection of colorful neurons to see how signals travel across the axon, from one end to the other, allowing nerve cells to communicate.


  • Several chenille sticks (pipe cleaners)
  • Beads
  • Scissors
  • Watercolor paint or pens and paper (optional)


1 Cut several chenille sticks into pieces 2 to 4 inches (5 to 10 cm) long. These will form the dendrites of the neuron. Fig. 1, Fig. 2. Lay one long, uncut chenille stick across another, around 2 inches (5 cm) from the top to form a cross. Fig. 3.


Fig. 1. Gather chenille sticks (pipe cleaners), beads, and scissors for this project.


Fig. 2. Cut some of the chenille sticks into pieces 5 to 10 cm long.


Fig. 3. Lay one uncut chenille stick across another one to form a cross shape.

2 Twist the short piece of the cross down over the other pipe cleaner and twist it around itself to form a T shape. The vertical part of the T will represent the axon of the neuron. Fig. 4.


Fig. 4. Twist the chenille stick down and around the long stem to form a T.

3 Twist several short chenille sticks around the top of the T to form branches. Fig. 5.


Fig. 5. Twist short pieces of chenille sticks around the arms of the T.

4 Wrap the top of the T around itself to form a ball, with the dendrite branches bristling out. The ball represents the cell body of the neuron. Fig. 6.


Fig. 6. Wrap the branches of the T to form a ball, representing the cell body of the neuron.

5 Twist a few more short chenille sticks onto the dendrites attached to the cell body.

6 Thread a bead onto the long axon portion of the neuron and twist the bottom into a small ball, or twist on another piece of chenille stick so the bead can’t fall off. This end of the neuron represents the synaptic terminal. Fig. 7 (here).


Fig. 7. Thread a bead onto the long axon portion of the neuron to represent the electrical signal.

7 The bead represents an electrical signal. Position the bead near the cell body and dendrites and slide the bead across the axon to the synaptic terminal to see how a signal moves from one end of a nerve cell to the other. Fig. 8.


Fig. 8. Slide the bead from the dendrites to the synaptic terminal to see how electrical signals travel.


Make several nerve cells and arrange them so synaptic terminals are near dendrites to create a neural network that demonstrates how signals travel from cell to cell. Fig. 9.


Fig. 9. Make several model neurons and use them to see how nerve cells send signals to one another.

Find microscopic images of nerve cells stained using the Golgi technique (silver impregnation) and draw or paint them. Look up the artwork of Santiago Ramón y Cajal for inspiration.


Thanks to a network of nerve cells, called neurons, when you touch something hot, you pull your hand away very quickly. These cells instantaneously carry the signal from your fingertips to your brain using electrical and chemical signals. Neurons can be very small or very long. Giraffes have neurons which are almost fifteen feet long, but they are so thin that they can only be seen under a microscope.

Branching dendrites on nerve cells carry information to the neuron’s cell body, which transmits a signal to the axon. An electrical signal travels across the axon to the synaptic terminal, which then sends a chemical signal to nearby neurons. The chemical signal moves across a small gap to the dendrites of other neurons, which can pass it on to their neighbors.

To study nerve cells under a microscope, tissue must be stained using dyes that are absorbed into the cells. Santiago Ramón y Cajal used a technique called silver impregnation to study nerve cells. In his own words, the method made the cells appear “colored brownish black even to their finest branchlets, standing out with unsurpassable clarity upon a transparent yellow background.” An improved version of the technique, also called the “Golgi Method,” is still used by scientists today.

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