History of synesthesia research
Encyclopedia
Synesthesia
is a neurological condition in which two or more bodily sense
s are coupled. For example, in a form of synesthesia known as grapheme-color synesthesia
, letters or numbers may be perceived as inherently colored. Historically, the most commonly described form of synesthesia (or synesthesia-like mappings) has been between sound and vision, e.g. the hearing of colors in music.
page).
John Locke
in An Essay Concerning Human Understanding
(1689) reports:
Whether this is an actual instance of synesthesia, or simply reflects metaphorical speech, is debated. A similar example appears in Leibniz's New Essays on Human Understanding
(written in 1704, but not published until 1764); indeed given that the New Essays is intended as a rebuttal to Locke, it may even have been the same individual. Although it is mainly speculation, there is reason to believe that the person Locke referred to was the mathematician and scientist Nicholas Saunderson
, who held the Lucasian professor chair at Cambridge University, and whose general prominence would have made his statements noticeable. In Letters on the blind, Denis Diderot
, one of Locke's followers, mentions Saunderson by name in related philosophical reflections.
In 1710, Thomas Woolhouse reported the case of another blind man who perceived colors in response to sounds. The first agreed upon account of synesthesia comes from Sachs in 1812, who reports on his colored vowels as part of his PhD dissertation (on his albinism), although its importance has only become apparent restrospectively.
Numerous other philosophers and scientists, including Isaac Newton
(1704), Erasmus Darwin
(1790) and Wilhelm Wundt
(1874) may have referred to synesthesia, or at least synesthesia-like mappings between colors and musical notes. Henry David Thoreau
remarked in a letter to Ralph Waldo Emerson
in 1848 that a child he knew had asked him "if I did not use ‘colored words.’ She said that she could tell the color of a great many words, and amused the children at school by so doing."
, Gustav Fechner
reported on a first empirical survey of colored letter photisms among 73 synesthetes in 1871, followed in the 1880s by Francis Galton
. These early investigations aroused little interest, and the phenomenon was first brought to the attention of the scientific community. Research into synesthesia proceeded briskly, with researchers from England, Germany, France and the United States all investigating the phenomenon. These early research years corresponded with the founding of psychology as a scientific field (see history of psychology
). By 1926, Mahling cites 533 published papers dealing with colored hearing (or hearing → color synesthesia) alone.
Although there is still debate as to when the first international academic conference to seriously look at synesthesia took place, a likely candidate is the following: From March 2 through 5th of 1927, Georg Anschütz (who was once a student of Alfred Binet
) presided over the convening of the first Kongresse zur Farbe-Ton-Forschung (Congress for Color-Tone Research), in Hamburg, Germany. A 2nd congress took place 1 – 5 October, 1930, in Hamburg, Germany ; the 3rd October 2 – 7, 1933; and the 4th and final conference in this series took place October 4 – 10, 1936.
In addition to drawing concerted scientific interest, the phenomenon of synesthesia started arousing interest in the salons of fin de siecle Europe. The French Symbolist poets Arthur Rimbaud
and Charles Baudelaire
wrote poems which focused on synesthetic experience. Baudelaire's (1857) (full text available here) introduced the Romantic notion that the senses can and should intermingle. Kevin Dann argues that Baudelaire probably learned of synesthesia from reading medical textbooks that were available in his home, and it is generally agreed that neither Baudelaire, nor Rimbaud were true synesthetes. Rimbaud, following Baudelaire, wrote Voyelles (1871) (full text available here) which was perhaps more important than in popularizing synesthesia. Numerous other composers, artists and writers followed suit, making synesthesia well-known among the artistic community of the day.
Due to the difficulties in assessing and measuring subjective internal experiences, and the rise of behaviorism
in psychology, which banished any mention of internal experiences, the study of synesthesia gradually waned during the 1930s. Marks lists 44 papers discussing colored hearing from 1900 to 1940, while in the following 35 years from 1940 to 1975, only 12 papers were published on this topic. Cretien van Campen
graphed the number of publications in the period 1780 - 2000 and noticed a revival of synesthesia studies from the 1980s.
had begun to make discussion of internal states and even the study of consciousness
respectable again, scientists began to once again examine this fascinating phenomenon. Led by Lawrence E. Marks and Richard Cytowic in the United States, and by Simon Baron-Cohen
and Jeffrey Gray in England, research into synesthesia began by exploring the reality, consistency and frequency of synesthetic experiences. In the late 1990s, researchers began to turn their attention towards grapheme-color synesthesia, one of the most common and easily studied forms of synesthesia. In 2006, the journal Cortex published a special issue on synesthesia, composed of 26 articles from individual case reports to functional neuroimaging
studies of the neural basis of synesthesia
. Synesthesia has been the topic of several recent scientific books and novels and a recent short film has even included characters who experience synesthesia (for more information, see the main synesthesia
page).
Mirroring these developments in the professional community, synesthetes and synesthesia researchers have come together to found several societies dedicated to research and education about synesthesia, its consequences and uses. In 1995, the American Synesthesia Association
was founded, and has been having annual meetings since 2001. In England, the UK Synaesthesia Association
, arose out of a similar desire to bring together synesthetes and the people who study them, and has held two conferences (in 2005 and 2006). Similarly, since its inception in 1993, Sean A. Day has administered the "synesthesia list", an e-mail list for synesthetes and researchers around the world. With increased scientific knowledge and public outreach, awareness of this condition is growing worldwide.
Synesthesia
Synesthesia , from the ancient Greek , "together," and , "sensation," is a neurologically based condition in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway...
is a neurological condition in which two or more bodily sense
Sense
Senses are physiological capacities of organisms that provide inputs for perception. The senses and their operation, classification, and theory are overlapping topics studied by a variety of fields, most notably neuroscience, cognitive psychology , and philosophy of perception...
s are coupled. For example, in a form of synesthesia known as grapheme-color synesthesia
Grapheme-color synesthesia
Grapheme → color synesthesia is a form of synesthesia in which an individual's perception of numbers and letters is associated with the experience of colors. Like all forms of synesthesia, grapheme → color synesthesia is involuntary, consistent, and memorable...
, letters or numbers may be perceived as inherently colored. Historically, the most commonly described form of synesthesia (or synesthesia-like mappings) has been between sound and vision, e.g. the hearing of colors in music.
Early investigations of colored hearing
The interest in colored hearing, i.e. the co-perception of colour in hearing sounds or music, dates back to Greek antiquity, when philosophers were investigating whether the colour (chroia, what we now call timbre) of music was a physical quality that could be quantified. The seventeenth-century physicist Isaac Newton tried to solve the problem by assuming that musical tones and colour tones have frequencies in common. The age-old quest for colour-pitch correspondences in order to evoke perceptions of coloured music finally resulted in the construction of color organs and performances of colored music in concert halls at the end of the nineteenth century. (For more information, see the synesthesia in artSynesthesia in art
The phrase synesthesia in art has historically referred to a wide variety of artistic experiments that have explored the co-operation of the senses The phrase synesthesia in art has historically referred to a wide variety of artistic experiments that have explored the co-operation of the senses The...
page).
John Locke
John Locke
John Locke FRS , widely known as the Father of Liberalism, was an English philosopher and physician regarded as one of the most influential of Enlightenment thinkers. Considered one of the first of the British empiricists, following the tradition of Francis Bacon, he is equally important to social...
in An Essay Concerning Human Understanding
An Essay Concerning Human Understanding
First appearing in 1690 with the printed title An Essay Concerning Humane Understanding, An Essay Concerning Human Understanding by John Locke concerns the foundation of human knowledge and understanding. He describes the mind at birth as a blank slate filled later through experience...
(1689) reports:
Whether this is an actual instance of synesthesia, or simply reflects metaphorical speech, is debated. A similar example appears in Leibniz's New Essays on Human Understanding
New Essays on Human Understanding
New Essays on Human Understanding is a chapter-by-chapter rebuttal by Gottfried Leibniz of John Locke's major work, An Essay Concerning Human Understanding. It is one of only two full-length works by Leibniz...
(written in 1704, but not published until 1764); indeed given that the New Essays is intended as a rebuttal to Locke, it may even have been the same individual. Although it is mainly speculation, there is reason to believe that the person Locke referred to was the mathematician and scientist Nicholas Saunderson
Nicholas Saunderson
Nicholas Saunderson was an English scientist and mathematician. According to one leading historian of statistics, he may have been the earliest discoverer of Bayes theorem.-Biography:...
, who held the Lucasian professor chair at Cambridge University, and whose general prominence would have made his statements noticeable. In Letters on the blind, Denis Diderot
Denis Diderot
Denis Diderot was a French philosopher, art critic, and writer. He was a prominent person during the Enlightenment and is best known for serving as co-founder and chief editor of and contributor to the Encyclopédie....
, one of Locke's followers, mentions Saunderson by name in related philosophical reflections.
In 1710, Thomas Woolhouse reported the case of another blind man who perceived colors in response to sounds. The first agreed upon account of synesthesia comes from Sachs in 1812, who reports on his colored vowels as part of his PhD dissertation (on his albinism), although its importance has only become apparent restrospectively.
Numerous other philosophers and scientists, including Isaac Newton
Isaac Newton
Sir Isaac Newton PRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived."...
(1704), Erasmus Darwin
Erasmus Darwin
Erasmus Darwin was an English physician who turned down George III's invitation to be a physician to the King. One of the key thinkers of the Midlands Enlightenment, he was also a natural philosopher, physiologist, slave trade abolitionist,inventor and poet...
(1790) and Wilhelm Wundt
Wilhelm Wundt
Wilhelm Maximilian Wundt was a German physician, psychologist, physiologist, philosopher, and professor, known today as one of the founding figures of modern psychology. He is widely regarded as the "father of experimental psychology"...
(1874) may have referred to synesthesia, or at least synesthesia-like mappings between colors and musical notes. Henry David Thoreau
Henry David Thoreau
Henry David Thoreau was an American author, poet, philosopher, abolitionist, naturalist, tax resister, development critic, surveyor, historian, and leading transcendentalist...
remarked in a letter to Ralph Waldo Emerson
Ralph Waldo Emerson
Ralph Waldo Emerson was an American essayist, lecturer, and poet, who led the Transcendentalist movement of the mid-19th century...
in 1848 that a child he knew had asked him "if I did not use ‘colored words.’ She said that she could tell the color of a great many words, and amused the children at school by so doing."
19th century investigations
The first medical description of colored hearing is found in a thesis by the German physician Sachs in 1812. The father of psychophysicsPsychophysics
Psychophysics quantitatively investigates the relationship between physical stimuli and the sensations and perceptions they effect. Psychophysics has been described as "the scientific study of the relation between stimulus and sensation" or, more completely, as "the analysis of perceptual...
, Gustav Fechner
Gustav Fechner
Gustav Theodor Fechner , was a German experimental psychologist. An early pioneer in experimental psychology and founder of psychophysics, he inspired many 20th century scientists and philosophers...
reported on a first empirical survey of colored letter photisms among 73 synesthetes in 1871, followed in the 1880s by Francis Galton
Francis Galton
Sir Francis Galton /ˈfrɑːnsɪs ˈgɔːltn̩/ FRS , cousin of Douglas Strutt Galton, half-cousin of Charles Darwin, was an English Victorian polymath: anthropologist, eugenicist, tropical explorer, geographer, inventor, meteorologist, proto-geneticist, psychometrician, and statistician...
. These early investigations aroused little interest, and the phenomenon was first brought to the attention of the scientific community. Research into synesthesia proceeded briskly, with researchers from England, Germany, France and the United States all investigating the phenomenon. These early research years corresponded with the founding of psychology as a scientific field (see history of psychology
History of psychology
The history of psychology as a scholarly study of the mind and behavior dates back to the Ancient Greeks. There is also evidence of psychological thought in ancient Egypt. Psychology was a branch of philosophy until the 1870s, when psychology developed as an independent scientific discipline in...
). By 1926, Mahling cites 533 published papers dealing with colored hearing (or hearing → color synesthesia) alone.
Although there is still debate as to when the first international academic conference to seriously look at synesthesia took place, a likely candidate is the following: From March 2 through 5th of 1927, Georg Anschütz (who was once a student of Alfred Binet
Alfred Binet
Alfred Binet was a French psychologist who was the inventor of the first usable intelligence test, known at that time as the Binet test and today referred to as the IQ test. His principal goal was to identify students who needed special help in coping with the school curriculum...
) presided over the convening of the first Kongresse zur Farbe-Ton-Forschung (Congress for Color-Tone Research), in Hamburg, Germany. A 2nd congress took place 1 – 5 October, 1930, in Hamburg, Germany ; the 3rd October 2 – 7, 1933; and the 4th and final conference in this series took place October 4 – 10, 1936.
In addition to drawing concerted scientific interest, the phenomenon of synesthesia started arousing interest in the salons of fin de siecle Europe. The French Symbolist poets Arthur Rimbaud
Arthur Rimbaud
Jean Nicolas Arthur Rimbaud was a French poet. Born in Charleville, Ardennes, he produced his best known works while still in his late teens—Victor Hugo described him at the time as "an infant Shakespeare"—and he gave up creative writing altogether before the age of 21. As part of the decadent...
and Charles Baudelaire
Charles Baudelaire
Charles Baudelaire was a French poet who produced notable work as an essayist, art critic, and pioneering translator of Edgar Allan Poe. His most famous work, Les Fleurs du mal expresses the changing nature of beauty in modern, industrializing Paris during the nineteenth century...
wrote poems which focused on synesthetic experience. Baudelaire's (1857) (full text available here) introduced the Romantic notion that the senses can and should intermingle. Kevin Dann argues that Baudelaire probably learned of synesthesia from reading medical textbooks that were available in his home, and it is generally agreed that neither Baudelaire, nor Rimbaud were true synesthetes. Rimbaud, following Baudelaire, wrote Voyelles (1871) (full text available here) which was perhaps more important than in popularizing synesthesia. Numerous other composers, artists and writers followed suit, making synesthesia well-known among the artistic community of the day.
Due to the difficulties in assessing and measuring subjective internal experiences, and the rise of behaviorism
Behaviorism
Behaviorism , also called the learning perspective , is a philosophy of psychology based on the proposition that all things that organisms do—including acting, thinking, and feeling—can and should be regarded as behaviors, and that psychological disorders are best treated by altering behavior...
in psychology, which banished any mention of internal experiences, the study of synesthesia gradually waned during the 1930s. Marks lists 44 papers discussing colored hearing from 1900 to 1940, while in the following 35 years from 1940 to 1975, only 12 papers were published on this topic. Cretien van Campen
Cretien van Campen
Cretien van Campen is a Dutch author, editor and scientific researcher in social science and fine arts. He is the founder of Synesthetics Netherlands and is affiliated with the Netherlands Institute for Social Research...
graphed the number of publications in the period 1780 - 2000 and noticed a revival of synesthesia studies from the 1980s.
The modern renaissance
In the 1980s, as the cognitive revolutionCognitive revolution
The cognitive revolution is the name for an intellectual movement in the 1950s that began what are known collectively as the cognitive sciences. It began in the modern context of greater interdisciplinary communication and research...
had begun to make discussion of internal states and even the study of consciousness
Consciousness
Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...
respectable again, scientists began to once again examine this fascinating phenomenon. Led by Lawrence E. Marks and Richard Cytowic in the United States, and by Simon Baron-Cohen
Simon Baron-Cohen
Simon Baron-Cohen FBA is professor of Developmental Psychopathology in the Departments of Psychiatry and Experimental Psychology at the University of Cambridge in the United Kingdom. He is the Director of the University's Autism Research Centre, and a Fellow of Trinity College...
and Jeffrey Gray in England, research into synesthesia began by exploring the reality, consistency and frequency of synesthetic experiences. In the late 1990s, researchers began to turn their attention towards grapheme-color synesthesia, one of the most common and easily studied forms of synesthesia. In 2006, the journal Cortex published a special issue on synesthesia, composed of 26 articles from individual case reports to functional neuroimaging
Functional neuroimaging
Functional neuroimaging is the use of neuroimaging technology to measure an aspect of brain function, often with a view to understanding the relationship between activity in certain brain areas and specific mental functions...
studies of the neural basis of synesthesia
Neural basis of synesthesia
Synesthesia is a neurological condition in which two or more bodily senses are coupled. For example, in a form of synesthesia known as Grapheme → color synesthesia, letters or numbers may be perceived as inherently colored. In another, called number → form synesthesia, numbers are automatically and...
. Synesthesia has been the topic of several recent scientific books and novels and a recent short film has even included characters who experience synesthesia (for more information, see the main synesthesia
Synesthesia
Synesthesia , from the ancient Greek , "together," and , "sensation," is a neurologically based condition in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway...
page).
Mirroring these developments in the professional community, synesthetes and synesthesia researchers have come together to found several societies dedicated to research and education about synesthesia, its consequences and uses. In 1995, the American Synesthesia Association
American Synesthesia Association
The American Synesthesia Association is a not-for-profit academic and public society whose mission is to foster and promote the education and the advancement of knowledge of the phenomena of synesthesia, a neurological condition in which stimulation in one sensory modality leads to experiences in...
was founded, and has been having annual meetings since 2001. In England, the UK Synaesthesia Association
UK Synaesthesia Association
The UK Synaesthesia Association was originally founded by Professor Simon Baron-Cohen, Professor of Developmental Psychopathology at Cambridge University and a leading researcher into synaesthesia.-Activities:...
, arose out of a similar desire to bring together synesthetes and the people who study them, and has held two conferences (in 2005 and 2006). Similarly, since its inception in 1993, Sean A. Day has administered the "synesthesia list", an e-mail list for synesthetes and researchers around the world. With increased scientific knowledge and public outreach, awareness of this condition is growing worldwide.