by
Sandra Blakeslee
Reviewed by
William Morrow, 1999
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Review
According to many religions, our bodies are merely illusory frames, inhabited for a short while by the soul. In Phantoms in the Brain, neurologist V.S. Ramachandran and science writer Sandra Blakeslee provide thought-provoking examples of just how illusory our mental body images are. By itself, the brain creates subjective feelings, such as pain and joy, commonly regarded as characteristics of the soul. Could it be we are finally beginning to get a scientific handle on the soul?
A striking example of how our body images are remarkably malleable is the
following experiment: take a scarf, and two helpers (let us call them Anna
and Nina), and seat yourself, blindfolded, on a chair behind Anna. Tell
Nina to guide the index finger of your right hand to Anna's nose. Then with
your index finger repeatedly stroke and tap Anna's nose unpredictably, like
Morse code. At the same time, ask Nina to stroke and tap your nose with the index finger of her left
hand in exactly the same way. After 30 to 40 seconds your nose will seem to be the size of Pinocchio's. The more random and unpredictable the movements, the stronger this illusion. This is a
simple example of how quickly the brain constructs meaning on the basis of
the information present.
Phantom Pains
The brain's fundamental function seems to be to construct and attach
meaning to events. This can create bizarre conflicts, such as the
"Pinocchio nose" experiment described above, where an effect conflicts with
what we know logically to be the case. Characteristically the brain tries
to avoid these conflicts, in order to help us navigate our complex
environments.
However, this at times creates absurd situations. For example, neurological patients suffering from neglect disorders consistently deny the existence of all objects in one half of their visual field - including any part of their own bodies that lie in that field. Patients who have lost a hand may still insist they can feel the missing limb. Amputees also suffer from violent phantom pains in their missing limbs. This is a strange but important problem. How can pain in nonexistent body parts be cured?
The Whole Arm
Numerous medical strategies have been tried for many years. With pain in a
phantom hand, for instance, further amputation was attempted, first up to
the elbow and sometimes even as far as the shoulder. When that didn't work (which it rarely does), neurons were removed from the spinal cord. In some
cases, doctors even performed surgical intervention in the brain. All too often these treatments were at best ineffective, and had many unpleasant
side effects. Consequently, scientists became unwilling to accept phantom
pains as a real physiological disorder. Instead, some neo-Freudian
theoreticians saw them as repressed wishes for the lost body parts.
Of Fetishism and Orgasms
This was more or less the situation when some scientists, led by Ramachandran, came up with a bright idea. The pioneering research on epileptic patients by the neurosurgeon Wilder Penfield in the 1950s demonstrated how the body is represented as a map in the cortex of the brain. Importantly, these maps do not reflect the true proportions of the body: they are distorted. For instance, the face and genitals occupy a greater area in the brain than the elbow and toes; next to the area for the face we do not find the area for the upper body, but for the hand; next to the genitals, not the thighs but the feet are represented.
Now, what if part of the brain area for the hand were taken over by a neighboring area, in this case the face? Then stimulation of parts of the face should be felt in the amputated hand.
Surprisingly, that is exactly what Ramachandran discovered. An amputee's
whole hand could be found on his chin: not only could he feel needle pricks
there - he also felt them in his nonexistent hand.
Ramachandran thus demonstrated that the functions of large areas in the brain can be overtaken by neighboring areas. Previously, many scientists had not thought such reorganization was possible. An analogous effect has since, however, been demonstrated in violinists, who use a larger part of cortex than normal subjects to represent hands and fingers.
Interestingly, according to Ramachandran, similar mechanisms might explain
bizarre phenomena such as foot fetishism and orgasms in the foot; for since
the brain area for the genitals is right next to the feet, cross-talk may arise.
Amputation of the Phantom
Explaining phantom pains does not cure them, however. But then Ramachandran had another bright idea. At least half the cortex is used for vision, and vision itself has a controlling impact on our cognitive capacities. So he made a special mirror box, creating the illusion that one part of the box is a mirror of the other. When one hand was inserted into this, it looked as though there were two hands. This creates an illusion in which the missing hand seems to have magically returned.
Many patients have strong pains in their phantom limbs, especially in their
hands, which are often felt to be agonizingly clenched. This pain can be
alleviated by asking the patient to open and close both hands in the mirror
box. In one case the mirror box not only cured the pain but, in the
patient's view, even "amputated" the phantom hand (which probably had been
defined by the pain).
Laughter Until Death
Phantoms in the Brain contains many refreshing and original ideas. Just as the neurologist Oliver Sacks manages to relate important parts of human nature by describing a number of neurological disorders, Ramachandran achieves a similar effect in his descriptions of patients. Furthermore, he is not afraid to go out on a limb, as it were, to offer ingenious explanations of the phenomena he describes.
We are therefore taken on a tour of a number of interesting disorders, ranging from blindsight (blind patients able to see more than they realize), to a phantom pregnancy (labor pains occurring women who are not pregnant), to Capgras syndrome (the patient accuses close relatives of being impostors). Ramachandran describes rare neurological cases, such as a lady with a brain hemorrhage that made her laugh herself literally to death, or the woman who could not see movement, but only still pictures, and who therefore had severe problems crossing busy roads. We are also told of temporal lobe epileptics who are prone to attach deep cosmic significance to every event in their lives, and how damage to the frontal lobes can induce remarkable changes in personality.
Epistemology
This is an astute and admirable book. In places, however, the writing is uneven, with some tiresome and almost banal examples of where, for example, Baywatch should be represented in the brain. Yet those are minor faults in a remarkably readable book, dedicated to what Ramachandran calls (primarily to annoy philosophers) experimental epistemology.
The book culminates in an attempt to determine those parts of the brain that are
used to create the self. The self has a number of aspects, of which
embodiment, memory, executive functions, awareness, sociality, and unity may
all have equivalents in the brain.
Books such as Phantoms in the Brain give us ideas about where to look in the brain for answers to the big interesting questions of self and consciousness - even if the soul itself still eludes scientific inquiry.
Morten Kringelbach is a neuroscientist at the University of Oxford.
A man wearing an enormous bejeweled cross dangling on a gold chain sits in my office, telling me about his conversations with God, the "real meaning" of the cosmos and the deeper truth behind all surface appearances. The universe is suffused with spiritual messages, he says, if you just allow yourself to tune in. I glance at his medical chart, noting that he has suffered from temporal lobe epilepsy since early adolescence, and that is when "God began talking" to him. Do his religious experiences have anything to do with his temporal lobe seizures?
You may purchase this book (328 pp., paper) directly from:



Vilayanur S. Ramachandran - coauthor's home page at the Center for Brain and Cognition at University of California at San Diego.
Banishing the Ghosts - New Scientist review of Phantoms in the Brain.
Phantoms in Motion - describing Ramachandran's recent research on how patients may experience either voluntary or spontaneous movements of phantom limbs, even years after their losses. From Nature's Helix Service.
Mind over Body - a feature from Scientific American describing the curious mental disability called anosognosia (from Greek meaning "loss of knowledge.")
Touched by the Word of God - from New Scientist on Ramachandran's research of how people with temporal lobe epilepsy (TLE) often become obsessively religious.