Santiago Ramón y Cajal (Spanish: [sanˈtjaɣo raˈmon i kaˈxal]; 1 May 1852 – 17 October 1934) was a Spanish scientist who studied the brain, nerves, and tissues. He specialized in the structure of the brain and the central nervous system. In 1906, he and Camillo Golgi won the Nobel Prize in Physiology or Medicine. Ramón y Cajal was the first person from Spain to receive a scientific Nobel Prize. His research on the tiny details of brain cells helped start modern neuroscience.

Many of his drawings, which show the tree-like shapes of brain cells, are still used today for teaching and learning purposes. These drawings have been used since the middle of the 20th century.

Biography

Santiago Ramón y Cajal was born on May 1, 1852, in the town of Petilla de Aragón, Navarre, Spain. As a child, he moved between schools often due to behavior that was considered poor, rebellious, and disrespectful to authority. At age 11, he showed his early talent and rebellious nature by being sent to jail in 1863 for breaking a neighbor's gate with a homemade cannon. He loved painting, art, and gymnastics, but his father did not support or encourage these talents, even though they later helped him succeed. His father sent him to work with a shoemaker and barber to help him gain discipline and stability.

In the summer of 1868, his father took him to graveyards to collect human remains for study. His early drawings of bones inspired him to study medicine. Ramón y Cajal attended the medical school at the University of Zaragoza, where his father taught anatomy. He graduated in 1873, at age 21, and then worked as a medical officer in the Spanish Army. He joined an expedition to Cuba in 1874–1875, where he became sick with malaria and tuberculosis. To help him recover, he stayed in the spa town of Panticosa in the Pyrenees mountains.

After returning to Spain, he earned his doctorate in medicine in Madrid in 1877. Two years later, he became director of the Anatomical Museum at the University of Zaragoza and married Silveria Fañanás García, with whom he had seven daughters and five sons. He worked at the University of Zaragoza until 1883, when he became an anatomy professor at the University of Valencia. His early research focused on the causes of inflammation, the germs that cause cholera, and the structure of cells and tissues.

In 1887, Ramón y Cajal moved to Barcelona for a teaching position. There, he learned about Golgi's method, a technique that uses chemicals to stain some neurons black while leaving other cells clear. He improved this method, which allowed him to study the brain and spinal cord, where neurons are tightly packed and hard to examine under a microscope. During this time, he created detailed drawings of brain tissue from many species and major brain areas.

In 1892, he became a professor in Madrid. In 1899, he became director of the National Institute of Hygiene. In 1922, he founded the Laboratory of Biological Investigations, later renamed the Cajal Institute. He died in Madrid on October 17, 1934, at age 82, still working on his research even as he neared the end of his life.

Political and religious views

In 1877, Ramón y Cajal, who was 25 years old, joined a Masonic lodge. In 1965, John Brande Trend wrote that Ramón y Cajal was a liberal in politics, an evolutionist in philosophy, and an agnostic in religion.

However, Ramón y Cajal did not feel embarrassed when he used the word "soul." Later, he expressed regret for leaving organized religion. Eventually, he came to believe in God as the creator of the world, as he stated during his first lecture at the Spanish Royal Academy of Sciences.

In addition to being a regenerationist, Ramón y Cajal was considered a Spanish nationalist and a centralist. In this sense, he viewed non-Spanish nationalisms, such as Catalan and Basque, as separatist movements. Although he accepted the Statute of Núria and supported the teaching of Catalan in university classes, he was not comfortable with these actions. In 1937, during the Spanish Civil War, he wrote in the Gaceta de Melilla about the need for an "iron surgeon," showing his support for the national-Catholic rebels against the Spanish Republic.

Discoveries and theories

Ramón y Cajal made important contributions to the study of the nervous system. Inspired by the work of Frederick C. Kenyon, he studied the insect visual nervous system with his colleague Domingo Sánchez y Sánchez. He was amazed by the many different types of neurons. He discovered the axonal growth cone and showed through experiments that nerve cells are not connected in a continuous way, as the reticular theory suggested at the time, but instead have spaces between them. This proved the idea later called "neuron theory" by Heinrich Waldeyer, which is now a key part of modern neuroscience. In 1894, he told the Royal Society of London that neurons in adults can grow and form new connections, which helps explain learning. This idea is seen as the beginning of the synaptic theory of memory.

He supported the idea that dendritic spines exist, though he did not realize they are where signals from other neurons connect. He believed nerve cells have a direction of function, and his student, Rafael Lorente de Nó, later expanded this research into cable theory and early studies of how nerve cells work together in circuits.

By drawing detailed pictures of nerve structures and describing different types of cells, he discovered a new kind of cell, later named the interstitial cell of Cajal (ICC). These cells are found among neurons in the smooth muscles of the digestive system. They help control the slow waves of muscle movement that push food through the gut and send signals from motor neurons to muscle cells.

In his 1894 Croonian Lecture, Cajal compared cortical pyramidal cells to trees, suggesting they might become more complex over time, like a tree growing new branches.

He studied psychological topics, such as using hypnotic suggestion to reduce pain, which he applied to help his wife during childbirth. A book he wrote about these subjects was lost during the Spanish Civil War.

While studying the optic chiasma, Cajal created a map-based theory that explained how nerve fibers cross over in the brain and how this might have evolved.

Distinctions

Ramón y Cajal received many awards, honors, and invitations to join important scientific groups during his career. He earned special degrees in medicine from Cambridge University and Würzburg University, as well as a special degree in philosophy from Clark University. In 1905, he became an honorary member of the American Association for Anatomy. The most well-known honor he received was the Nobel Prize in Physiology or Medicine in 1906, which he shared with the Italian scientist Camillo Golgi. They were recognized for their research on the structure of the nervous system. This caused some disagreement because Golgi strongly supported a different idea about the nervous system than Cajal did. Before Cajal’s work, the Norwegian scientist Fridtjof Nansen had already discovered that nerve cells are connected in certain sea creatures, but Cajal did not mention Nansen’s findings. Cajal was also an International Member of the United States National Academy of Sciences and the American Philosophical Society.

In society and culture

In 1906, Joaquin Sorolla y Bastida painted an official portrait of Cajal to celebrate his Nobel Prize win.

Cajal posed for a statue made by Mariano Benlliure. The statue was placed in 1924 in the Paraninfo building at the School of Medicine of the University of Zaragoza.

In 1931, a full-body statue of Cajal was unveiled in Madrid, Spain. The statue is 3 meters (about 10 feet) tall and stands on a narrow pedestal. It was created by Lorenzo Domínguez, a Chilean medical student.

In 1935, El Banco De España released a 50 peseta banknote. The front showed a portrait of Cajal, and the back showed the Cajal Monument in Retiro Park.

In 1982, a Spanish TV mini series titled Ramón y Cajal: Historia de una voluntad was created.

In 2003, the first major exhibition of Cajal's scientific drawings opened in Madrid, Spain. The exhibition included hundreds of restored original drawings, micrographic slides, and personal photographs by Cajal. A catalog titled Santiago Ramon y Cajal (1852–2003) Ciencia y Arte was published, featuring high-quality reproductions of his work. The exhibition was curated by several experts, including Santiago Ramón y Cajal Junquera, Miguel Ángel Freire Mallo, Paloma Esteban Leal, and others.

In 2005, the asteroid 117413 Ramonycajal was named after Cajal by Juan Lacruz.

In 2007, sculptures of Severo Ochoa and Santiago Ramón y Cajal, created by Víctor Ochoa, were unveiled at the Spanish National Research Council headquarters in Madrid, Spain.

The Santiago Ramón y Cajal Museum in Ayerbe, Huesca, Spain, opened in 2013. It is located in Cajal's childhood home, where he lived with his family for ten years.

In 2014, the National Institutes of Health started an ongoing exhibition of Cajal's original drawings at the John Porter Neuroscience Research Center in Bethesda, MD, USA. The exhibition was led by Jeffery Diamond and Christopher Thomas, with collaboration from the Instituto Cajal in Madrid, Spain. The display also included artwork by Rebecca Kamen and Dawn Hunter, inspired by Cajal's drawings. Hunter continued her project with a Fulbright España Senior Research Fellowship from 2017 to 2018.

A selection of Cajal's scientific drawings, personal photos, oil paintings, and pastel drawings were included in the 14th Istanbul Biennial, Saltwater, held in Istanbul, Turkey, from September 5 to November 1, 2015.

The exhibition Fisiología de los Sueños. Cajal, Tanguy, Lorca, Dalí… opened on October 5, 2015, and ended on January 16, 2016, at the University of Zaragoza, Spain. Cajal's work was the main focus, exploring how his drawings influenced Surrealism.

From January 31 to May 29, 2016, Cajal's work was featured in the re-opening exhibition of the University of California's Berkeley Art Museum and Pacific Film Archive, titled Architecture of Life. The exhibition's catalog had a drawing of the Purkinje Cell on the front cover.

The National Institutes of Health (USA) and the Instituto Cajal (Spain) held symposiums honoring Cajal in 2015 and 2017. The 2015 event, titled Bridging the Legacy of Santiago Ramón y Cajal, was held at the NIH. The 2017 event, New Opportunities for NIH-CSIC Collaboration, was held at the Instituto Cajal. Dawn Hunter's Cajal Inventory art project was displayed at the 2017 symposium.

Since 2001, the Spanish Ministry of Science has awarded over 200 postdoctoral scholarships each year to middle-career scholars. These are called "Ayudas a contratos Ramón y Cajal" in honor of Cajal.

An exhibition titled The Beautiful Brain: The Drawings of Santiago Ramón y Cajal traveled through North America from 2017 to 2019. It visited locations such as the Weisman Art Museum in Minneapolis, the Morris and Helen Belkin Art Gallery in Vancouver, the Grey Art Gallery in New York, the MIT Museum in Cambridge, and the Ackland Art Museum in Chapel Hill. A book titled The Beautiful Brain, published by Abrams, accompanied the exhibition.

In 2019, the University of Zaragoza, Spain, opened an exhibition titled Santiago Ramón y Cajal. 150 years at the University of Zaragoza. The exhibition ran from October 2019 to December 2019 and had a catalog with the same title.

A short documentary by REDES is available on YouTube.

From November 19, 2020, to December 5, 2021, the National Museum of Natural Sciences in Madrid, Spain, hosted an exhibition featuring Cajal's scientific drawings, photographs, equipment, and personal items from the Legado Cajal collection at the Instituto Cajal.

In 2020, over 75 volunteers from six countries created 81 hand-stitched panels of Cajal's images as part of The Cajal Embroidery Project. The panels were displayed by Edinburgh Neuroscience at the virtual FENS 2020 Forum and featured in The Lancet Neurology in 2021.

In 2017, UNESCO recognized Cajal's Legacy as a World Heritage treasure. A call for a dedicated museum to celebrate Cajal's work and the legacy of his students has been made.

Project Encephalon organized Cajal Week from May 1 to May 7, 2021, to celebrate Cajal's 169th birthday.

An English-language biography titled The Brain In Search Of Itself was published in 2022.

Publications

Santiago Ramón y Cajal published more than 100 scientific works and articles in Spanish, French, and German. Some of his important works include:

• Rules and advice for scientific research
• Histology
• Degeneration and regeneration of the nervous system
• Manual of normal histology and micrographic technique
• Elements of histology

A list of his books includes:

• Ramón y Cajal, Santiago (1905) [1890]. Manual de Anatomia Patológica General (Handbook of General Anatomical Pathology) (in Spanish) (fourth edition).
• Ramón y Cajal, Santiago; Richard Greeff (1894). Die Retina der Wirbelthiere: Untersuchungen mit der Golgi-cajal'schen Chromsilbermethode und der ehrlich'schen Methylenblaufärbung (Retina of Vertebrates) (in German). Bergmann.
• Ramón y Cajal, Santiago; L. Azoulay (1894). Les nouvelles idées sur la structure du système nerveux chez l'homme et chez les vertébrés (New Ideas on the Fine Anatomy of the Nerve Centres) (in French). C. Reinwald.
• Ramón y Cajal, Santiago; Johannes Bresler; E. Mendel (1896). Beitrag zum Studium der Medulla Oblongata: Des Kleinhirns und des Ursprungs der Gehirnnerven (in German). Verlag von Johann Ambrosius Barth.
• Ramón y Cajal, Santiago (1898). "Estructura del quiasma óptico y teoría general de los entrecruzamientos de las vías nerviosas." (Structure of the Chiasma Opticum and General Theory of the Crossing of Nerve Tracks) [Die Structur des Chiasma opticum nebst einer allgemeine Theorie der Kreuzung der Nervenbahnen (German, 1899, Verlag Joh. A. Barth)]. Rev. Trim. Micrográfica (in Spanish). 3: 15–65.
• Ramón y Cajal, Santiago (1899). Comparative study of the sensory areas of the human cortex. Clark University. p. 85.
• Ramón y Cajal, Santiago (1899–1904). Textura del sistema nervioso del hombre y los vertebrados (in Spanish). Madrid. ISBN 978-84-340-1723-8. {{cite book}}: ISBN / Date incompatibility (help) —— (1909). Histologie du système nerveux de l'homme & des vertébrés (in French) – via Internet Archive. —— (2002-10-14). Texture of the Nervous System of Man and the Vertebrates. Springer. ISBN 978-3-211-83202-8.
• Ramón y Cajal, Santiago (1906). Studien über die Hirnrinde des Menschen v.5 (Studies about the Meninges of Man) (in German). Johann Ambrosius Barth.
• Ramón y Cajal, Santiago (1999) [1897]. Advice for a Young Investigator. Translated by Neely Swanson and Larry W. Swanson. Cambridge: MIT Press. ISBN 0-262-68150-1.
• Ramón y Cajal, Santiago; Domingo Sánchez y Sánchez (1915). Contribución al conocimiento de los centros nerviosos de los insectos (in Spanish). Madrid: Imprenta de Hijos de Nicolas Moya.
• Ramón y Cajal, Santiago (1937). Recuerdos de mi Vida (in Spanish). Cambridge: MIT Press. ISBN 84-206-2290-7. {{cite book}}: ISBN / Date incompatibility (help).

In 1905, he published five science-fiction stories called Vacation Stories under the pen name Dr. Bacteria.

Gallery of drawings

• First illustration of the nervous system by Cajal in 1888. (A) First page of the article. (B) Vertical section of a cerebellum part in a hen. (C) Cerebellum of an adult bird. (D) Closer look at (C) showing Purkinje cell. (E) Dendrite of the Purkinje cell.
• Drawing of the nerve connections in a rodent hippocampus. Histologie du Système Nerveux de l'Homme et des Vertébrés, Vols. 1 and 2. A. Maloine. Paris. 1911.
• Drawing of cells in a chick cerebellum, from Estructura de los centros nerviosos de las aves, Madrid, 1905.
• Drawing of a section through the optic tectum of a sparrow, from Estructura de los centros nerviosos de las aves, Madrid, 1905.
• From Structure of the Mammalian Retina, Madrid, 1900.
• Drawing of Purkinje cells (A) and granule cells (B) in a pigeon cerebellum by Santiago Ramón y Cajal, 1899. Instituto Santiago Ramón y Cajal, Madrid, Spain.
• Drawing of Cajal-Retzius cells, 1891.
• Drawn in 1899, taken from the book Comparative study of the sensory areas of the human cortex.
• Diagram of the visual map theory (1898). O=Optic chiasm; C=Visual (and motor) cortex; M, S=Decussating pathways; R, G: Sensory nerves, motor ganglia.
• Purkinje cell of the human cerebellum. Golgi method. -a, axon; b, recurrent collateral; c and d, spaces in the dendritic arborization for stellate cells, by Santiago Ramón y Cajal. (See Fig. 9 in Ref.)