V. S. Ramachandran
Vilayanur Subramanian Ramachandran
10 August 1951
|Known for||Research in neurology, visual perception, phantom limbs, synesthesia, autism, body integrity identity disorder, mirror therapy|
|Awards||Henry Dale Medal (2005), Padma Bhushan (2007), Scientist of the Year (ARCS Foundation) (2014)|
|Institutions||University of California, San Diego|
Vilayanur Subramanian Ramachandran (born 10 August 1951) is an Indian-American neuroscientist. He is known for his wide-ranging experiments and theories in behavioral neurology, including the invention of the mirror box. Ramachandran is a distinguished professor in UCSD's Department of Psychology, where he is the director of the Center for Brain and Cognition.
After earning a medical degree in India, Ramachandran studied experimental neuroscience at Cambridge, obtaining his PhD there in 1978. Most of his research has been in the fields of behavioral neurology and visual psychophysics. After early work on human vision, Ramachandran turned to work on wider aspects of neurology including phantom limbs and phantom pain. Ramachandran invented mirror therapy which is now used to treat amputees with phantom limb pain and also to help restore motor control in stroke victims with weakened limbs.
Ramachandran's popular books Phantoms in the Brain (1998), The Tell-Tale Brain (2010), and others describe neurological and clinical studies of people with synesthesia, Capgras syndrome, and a wide range of other unusual conditions. Ramachandran has also described his work in many public lectures, including lectures for the BBC, and two official TED talks. Both his scientific research and his popularization of science have been recognized with multiple awards.
Ramachandran was born in 1951 in Tamil Nadu, India. His mother had a degree in mathematics. His grandfather was Alladi Krishnaswamy Iyer, one of the framers of India's constitution.
Ramachandran's father, V. M. Subramanian, was an engineer who worked for the U.N. Industrial Development Organization and served as a diplomat in Bangkok, Thailand. Ramachandran attended schools in Madras, and British schools in Bangkok.
Ramachandran, whose father wanted him to become a physician rather than a researcher, obtained an M.B.B.S. from Stanley Medical College in Chennai, India.
In 1978, Ramachandran obtained a Ph.D. from Trinity College at the University of Cambridge. Later he moved to the US, where he spent two years at Caltech as a research fellow working with Jack Pettigrew before being appointed assistant professor of psychology at the University of California, San Diego in 1983. He became a full professor there in 1998. He currently holds the rank of distinguished professor in the UCSD Psychology Department, and is the director of its Center for Brain and Cognition, where he works with graduate students and researchers from UCSD and elsewhere on emerging theories in neuroscience. As of July 2019, Ramachandran is also a professor in the UCSD Medical School's Neurosciences program. and an adjunct professor at the Salk Institute for Biological Studies.
In 1987, Ramachandran married a fellow-scientist who became his frequent co-author as Diane Rogers-Ramachandran. They have two sons.
Ramachandran's scientific work can be divided into two phases. From the early 1970s until the late 1980s, Ramachandran's work focused almost exclusively on human visual processing, especially on stereopsis. Ramachandran began publishing research in this area beginning in 1972, with a paper in Nature while still a student at Stanley Medical College.
In 1991, Ramachandran was inspired by Tim Pons's research on cortical plasticity. Pons demonstrated cortical reorganization in monkeys after the amputation of a finger. Ramachandran was one of the first researchers to recognize the potential of neuroimaging technology to demonstrate the plastic changes that take place in the human cortex after amputation. Ramachandran then began research on phantom limbs, but later moved on to study a wider range of neurological mysteries, including body integrity identity disorder and the Capgras delusion.
Ramachandran has encountered skepticism about some of his theories. Ramachandran has responded, "I have—for better or worse—roamed the whole landscape of visual perception, stereopsis, phantom limbs, denial of paralysis, Capgras syndrome, synaesthesia, and many others."
Ramachandran has served as a consultant in areas such as forensic psychology and the neuroscience of weight reduction. In 2007, Ramachandran served as an expert witness on pseudocyesis (false pregnancy) at the trial of Lisa M. Montgomery. Ramachandran has served as a consultant to the Modius company which is developing weight reduction technology that relies on electrically stimulating parts of the brain that control weight loss. Ramachandran is collaborating with Indian doctors doing research on Mucuna pruriens, an ayurvedic (Indian natural medicine) therapy for Parkinson's disease.
In his scientific work, Ramachandran often uses simple equipment, such as mirrors or old-fashioned stereoscopes, rather than complex brain imaging technologies such as fMRI. Ramachandran has been outspoken about his intuition-based approach to studying the brain. In an interview with Frontline magazine Ramachandran stated:
Intuition is what gets you started; then you need empirical studies... brain-imaging technology often lulls you into a false sense of having understood what's going on. So sometimes, not having technology - that's my own approach and that of some of my colleagues, we use it only when it's absolutely essential, just like medical diagnostics. We rely more on intuition in doing simple experiments, because if you rely on fancy medical imaging, you become less creative.
Main article: Phantom limb
When an arm or leg is amputated, patients often continue to feel vividly the presence of the missing limb as a "phantom limb" (an average of 80%). Building on earlier work by Ronald Melzack (McGill University) and Timothy Pons (NIMH), Ramachandran theorized that there was a link between the phenomenon of phantom limbs and neural plasticity in the adult human brain. To test this theory, Ramachandran recruited amputees, so that he could learn more about if phantom limbs could "feel" a stimulus to other parts of the body.
In 1992, in collaboration with T.T. Yang, S. Gallen, and others at the Scripps Research Institute who were conducting MEG research, Ramachandran initiated a project to demonstrate that there had been measurable changes in the somatosensory cortex of a patient who had undergone an arm amputation.
Ramachandran theorized that there was a relationship between the cortical reorganization evident in the MEG image and the non-painful referred sensations he had observed in other subjects.
Later researchers found that non-painful phantom limbs correlated less with motor or somatosensory plasticity than painful phantom limbs. Recent research has also shown that the peripheral nervous system is involved in painful phantom limb phenomena.
Research continues into more precise mechanisms and explanations.
Main article: Mirror box
Writing in 2009, John Colapinto (author of Ramachandran's profile in The New Yorker) said that mirror box therapy for amputees was Ramachandran's most noted achievement.
Ramachandran thought that phantom pain might be caused by the mismatch between different parts of an amputee's nervous systems: the visual system says the limb is missing, but the somatosensory system (processing body sensations such as touch and limb position) says the limb is still there. The so-called mirror box was a simple apparatus that uses a mirror reflecting an amputee's good arm so it appears to be the extension of the one missing:
They put their surviving arm through a hole in the side of a box with a mirror inside, so that, peering through the open top, they would see their arm and its mirror image, as if they had two arms. Ramachandran then asked them to move both their intact arm and, in their mind, their phantom arm—to pretend that they were conducting an orchestra, say. The patients had the sense that they had two arms again.
Ramachandran found that in some cases restoring movement to a paralyzed phantom limb reduced the pain experienced. In 1999 Ramachandran and Eric Altschuler expanded the mirror technique from amputees to improving the muscle control of stroke patients with weakened limbs. As Deconick et al. state in a 2014 review, the mechanism of improved motor control may differ from the mechanism of pain relief.
Despite the introduction of mirror therapy in the late 1990s, little research was published on it before 2009, and much of the research since then has been of contested quality. Out of 115 publications between 2012 and 2017 about using mirror therapy to treat phantom limb pain, a 2018 review, found only 15 studies whose scientific results should be considered. From these 15 studies, the reviewers concluded that "MT seems to be effective in relieving PLP, reducing the intensity and duration of daily pain episodes. It is a valid, simple, and inexpensive treatment for PLP." Similarly, a 2017 review that studied a wider range of uses for mirror therapy, concluded, "Mirror therapy has been used to treat phantom limb pain, complex regional pain syndrome, neuropathy and low back pain. The mechanism of action of mirror therapy remains uncertain, and the evidence for clinical efficacy of mirror therapy is encouraging, but not yet definitive."
Main article: Mirror neuron
Mirror neurons were first reported in a paper published in 1992 by a team of researchers led by Giacomo Rizzolatti at the University of Parma. According to Rizzolati, "Mirror neurons are a specific type of visuomotor neuron that discharge both when a monkey executes a motor act and when it observes a similar motor act performed by another individual."
In 2000, Ramachandran made what he called some "purely speculative conjectures" that "mirror neurons [in humans] will do for psychology what DNA did for biology: they will provide a unifying framework and help explain a host of mental abilities that have hitherto remained mysterious and inaccessible to experiments."
Ramachandran has suggested that research into the role of mirror neurons could help explain a variety of human mental capacities such as empathy, imitation learning, and the evolution of language. In a 2001 essay for Edge, Ramachandran speculated that
I suggested that in addition to providing a neural substrate for figuring out another persons intentions...the emergence and subsequent sophistication of mirror neurons in hominids may have played a crucial role in many quintessentially human abilities such as empathy, learning through imitation (rather than trial and error), and the rapid transmission of what we call "culture". (And the "great leap forward" — the rapid Lamarckian transmission of "accidental") one-of-a kind inventions.
Ramchandran's speculations about the connection of mirror neurons with empathy have been contested by some authors and supported by others.
Main article: Mechanism of autism
In 1999, Ramachandran, in collaboration with then post-doctoral fellow Eric Altschuler and colleague Jaime Pineda, hypothesized that a dysfunction of mirror neuron activity might be responsible for some of the symptoms and signs of autism spectrum disorders. Between 2000 and 2006 Ramachandran and his colleagues at UC San Diego published a number of articles in support of this theory, which became known as the "Broken Mirrors" theory of autism. Ramachandran and his colleagues did not measure mirror neuron activity directly; rather they demonstrated that children with ASD showed abnormal EEG responses (known as Mu wave suppression) when they observed the activities of other people. In The Tell-Tale Brain (2010), Ramachandran states that the evidence for mirror-neuron dysfunction in autism is "compelling but not conclusive."
The contention that mirror neurons play a role in autism has been extensively discussed and researched.
Main article: Synesthesia
Ramachandran was one of the first scientists to theorize that grapheme-color synesthesia arises from a cross-activation between brain regions. Ramachandran and his graduate student, Ed Hubbard, conducted research with functional magnetic resonance imaging that found increased activity in the color recognition areas of the brain in synesthetes compared to non-synesthetes. Ramachandran has speculated that conceptual metaphors may also have a neurological basis in cortical cross-activation. As of 2015, the neurological basis of synesthesia had not been established.
Main article: Body Identity Integrity Disorder
In 2008, Ramachandran, along with David Brang and Paul McGeoch, published the first paper to theorize that apotemnophilia is a neurological disorder caused by damage to the right parietal lobe of the brain. This rare disorder, in which a person desires the amputation of a limb, was first identified by John Money in 1977. Building on medical case studies that linked brain damage to syndromes such as somatoparaphrenia (lack of limb ownership) the authors speculated that the desire for amputation could be related to changes in the right parietal lobe. In 2011 McGeoch, Brang and Ramachandran reported a functional imaging experiment involving four subjects who desired lower limb amputations. MEG scans demonstrated that their right superior parietal lobules were significantly less active in response to tactile stimulation of a limb that the subjects wished to have amputated, as compared to age/sex matched controls. The authors introduced the word "Xenomelia" to describe this syndrome, which is derived from the Greek for "foreign" and "limb".
Ramachandran is the author of several popular books on neurology such as Phantoms in the Brain (1998) and The Tell-Tale Brain (2010). Phantoms in the Brain became the basis for a 2001 PBS Nova special.
In 2003, the BBC chose Ramachandran to deliver that year's Reith Lectures, a series of radio lectures. Ramachandran's five radio talks on the topic "The Emerging Mind" were afterward published as a book with the same title.
Ramachandran has also given many talks, including TED talks in 2007 and 2010.
In 1997, Newsweek included him on a list of one hundred "personalities whose creativity or talent or brains or leadership will make a difference in the years ahead." In 2008, Foreign Policy included Ramachandran as one of its "World’s Top 100 Public Intellectuals." Similarly, in 2011, Time listed Ramachandran as one of "the most influential people in the world" on the "Time 100 list". Both the Time and the Prospect selections were decided by public voting on a longer list of names proposed by the organization.
Ramachandran has received many academic and other honors. For example, from his biography at Edge.org:
In 2005 he was awarded the Henry Dale Medal and elected to an honorary life membership by the Royal Institution of Great Britain, where he also gave a Friday evening discourse (joining the ranks of Michael Faraday, Thomas Huxley, Humphry Davy and others.) His other honours and awards include fellowships from All Souls College, Oxford, and from Stanford University (Hilgard Visiting Professor); the Presidential Lecture Award from the American Academy of Neurology, two honorary doctorates, the annual Ramon y Cajal award from the International Neuropsychiatry Society, and the Ariens Kappers medal from the Royal Netherlands Academy of Sciences.
In 2007, the president of India conferred on him the third highest civilian award and honorific title in India, the Padma Bhushan.
In 2014, the ARCS Foundation (Achievement Rewards for College Scientists) named Ramachandran its "Scientist of the Year."
Among amputees, 90% suffer from phantom limb pain, which can often cause excruciating discomfort.
In 1991, he became interested in the work of Tim Pons, a neuroscientist at the National Institute of Mental Health, who had been investigating the ability of neurons in the sensory cortex to adapt to change.
he first saw a fresh human brain as a student at the Stanley Medical College in Chennai in the 1970s.
Although the TellTale Brain does contain a lot of pop on the surface, the overall content is very much Popper
Ramachandran subsequently confirmed these results in a magnetoencephalography (MEG) study.
We realized that MEG studies could also be useful in determining whether remapping effects of the kind reported in monkeys would also be seen in human patients following amputation.
We conclude that new patterns of precisely organized and functionally effective connections can emerge in the adult human brain.
Currently, the most commonly posited CNS theory is the cortical remapping theory (CRT), in which the brain is believed to respond to limb loss by reorganizing somatosensory maps (16)... Debate still remains over the cause and maintaining factors of both phantom limbs and the associated pain.
It is unsurprising that with an amputation that such an intricate highway of information transport to and from the periphery may have the potential for problematic neurologic developments...Although phantom limb sensation has already been described and proposed by French military surgeon Ambroise Pare 500 years ago, there is still no detailed explanation of its mechanisms.
As a child, he was obsessed with magic tricks and illusions. So I think it’s no coincidence that the insight that made his name in science is his work using mirrors to alleviate phantom-limb pain, the excruciating, unremitting agony that many amputees feel in their missing limbs.
The mirror treatment, by contrast, targets the deranged sensor system itself. It essentially takes a misfiring sensor—a warning system functioning under an illusion that something is terribly wrong out in the world it monitors—and feeds it an alternate set of signals that calm it down. The new signals may even reset the sensor.
Use of the mirror may also help recruit the premotor cortex to help with motor rehabilitation...On a number of neurological and psychological levels, mirror therapy may help to reverse elements of learned disuse of the affected limb.
Up to the 26th November 2015, 85 articles were retrieved on the Medline, Cochrane and Embase databases with using the keywords phantom limb and mirror therapy. It was noted that from 2009, the number of articles increased markedly (Fig. 1), showing increased interest in MT following amputation.
It is a valid, simple, and inexpensive treatment for PLP. The methodological quality of most publications in this field is very limited, highlighting the need for additional, high-quality studies to develop clinical protocols that could maximise the benefits of MT for patients with PLP.
Thus I regard Rizzolati's discovery — and my purely speculative conjectures on their key role in our evolution — as the most important unreported story of the last decade.
Because these neurons appeared to be involved in abilities such as empathy and the perception of another individuals intentions, it seemed logical to hypothesize that a dysfunction of the mirror neuron system could result in some of the symptoms of autism.
Based on the current studies, we suggest a multilayer neural network model including the MNS on a first layer and transforming this information to a higher layer network responsible for reasoning
the BBC each year invites a leading figure to deliver a series of lectures on radio. The aim is to advance public understanding and debate about significant issues of contemporary interest.
Our object has been to take a snapshot of the future, framing some of the personalities whose creativity or talent or brains or leadership will make a difference in the years ahead.
In 2003 he gave the annual BBC Reith Lectures and was the first physician/psychologist to give the lectures since they were begun in 1949.
In non-AAN election years, this premier lecture is awarded to a neurologist chosen by the AAN president. In election years the lecture is presented by the outgoing president.
He has received many honors and awards including a fellowship from All souls college, Oxford, an honorary doctorate from Connecticut college, an honorary doctorate from IIT, Madras...
Established in 1954 by the president of India, the Padma Bhushan recognizes distinguished service of a high order to the nation, in any field.