Musicophilia
Page 14
Stephen Wiltshire, an autistic English prodigy, is widely known as a visual savant; he can produce amazingly detailed drawings of complex buildings and even whole cityscapes, sometimes after a single glance.4 He is able to hold these images in his mind, with little loss or distortion, for years on end. When he went to school at the age of six, his teacher commented that his drawings were the most “unchildlike drawings I have ever seen.”
Stephen is also a musical savant. Savant abilities usually appear before the age of ten, and this is especially so of musical savant talents. Yet when Stephen’s mentor, Margaret Hewson, phoned me to say, “Stephen has erupted musical powers— huge powers!” he was already sixteen. Like Martin, Stephen had absolute pitch and could instantly reproduce complex chords, play melodies he had never heard before, even if they were several minutes long, and transpose them easily into different keys. He also showed powers of improvisation. It is unclear why Stephen’s musical gifts seemed to appear relatively late. It seems likely that he had great musical potential from an early age, but, perhaps due to his own passivity and the focus of others on his visual gifts, this was not noticed. Perhaps, too, adolescence had an effect, as Stephen suddenly became fixated on Stevie Wonder and Tom Jones at this point, and loved to mimic their movements and mannerisms along with their music.
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IT IS A CHARACTERISTIC— indeed, the defining characteristic— of savant syndromes that there is a heightening of certain powers along with an impairment or poor development of other powers.5 The powers that are heightened in savant skills are always of a concrete sort, whereas those that are impaired are abstract and often linguistic— and there have been many speculations as to how such a conjunction of strength and weakness may come about.
It has been known for a century and a half that there is a relative (but not absolute) specialization in the functions of the two sides of the brain, with the development of abstract and verbal powers being especially associated with the left, or dominant, cerebral hemisphere and perceptual skills with the right. This hemispheric asymmetry is very pronounced in humans (and present in a lesser degree in primates and some other mammals) and is observable even in utero. In the fetus, and perhaps the very young child, the situation is reversed, for the right hemisphere develops earlier and more quickly than the left, allowing perceptual functions to be established in the first days and weeks of life. The left hemisphere takes longer to develop, but continues to change in fundamental ways after birth. And as it develops and acquires its own (largely conceptual and linguistic) powers, it starts to suppress or inhibit some of the (perceptual) functions of the right hemisphere.
The functional (and perhaps immunological) immaturity of the left hemisphere in utero and during infancy makes it unusually susceptible to damage, and if such damage occurs— so Geschwind and Galaburda have hypothesized— there may be a compensatory overdevelopment of the right hemisphere, an actual enlargement made possible by neuronal migration. This may reverse the normal course of events and produce an anomalous right-hemisphere dominance instead of the usual left-hemisphere dominance.6
Shifts to right-hemisphere dominance can also occur after birth, at least in the first five years of life, if the left hemisphere is damaged. (Geschwind’s interest in this phenomenon was ignited in part by the remarkable fact that a left hemispherectomy— a drastic procedure sometimes performed for intractable epilepsy, in which the entire left hemisphere is removed— does not render a young child permanently languageless but is followed by the development of language functions in the right hemisphere.) It seems quite possible that something like this happened with the three-year-old Martin, following his meningitis. Such hemispheric shifts may also occur, though to a lesser degree, in adults who have predominantly left-sided damage to the brain.
Savantlike talents may sometimes emerge in later life. There are several anecdotal descriptions of such an emergence following brain injuries, strokes, tumors, and frontotemporal dementia, especially if the damage is confined initially to the left temporal lobe. Clive Wearing, described in chapter 15, had a herpes encephalitis infection affecting especially his left frontal and temporal regions and, in addition to his devastating amnesia, developed a savantlike speed of calculation and punning.
The rapidity with which savant talents may emerge in such circumstances suggests a disinhibition or release of right-hemisphere functions from an inhibition or suppression normally exerted by the left temporal lobe.
In 1999, Allan Snyder and D. J. Mitchell inverted the usual question of why savant talents are so rare and asked instead: why don’t we all have savant talents? They suggested that the mechanism for such skills might reside in all of us in early life but that as the brain matures, they are inhibited, at least from conscious awareness. They theorized that savants might have “privileged access to lower levels of information not available through introspection.” Subsequently they started to test this theory experimentally using transcranial magnetic stimulation (TMS), which now allows a brief and virtually instantaneous way of inhibiting physiological functions in different parts of the brain. Using normal volunteers, they applied TMS to the left temporal lobe for a few minutes, in a stimulation designed to inhibit the abstract and conceptual thought governed by this area of the brain and, they hoped, to allow a transient release of perceptual functions in the right hemisphere. These experiments have produced modest but suggestive results, seemingly improving skills like drawing, calculating, and proofreading for a few minutes. (Bossomaier and Snyder are also investigating whether absolute pitch can be released by TMS.)7
Similar techniques have been used by Robyn Young and her colleagues, who found in one study that they could duplicate the release effect but only in five out of seventeen subjects. They concluded that “these mechanisms are not available to everyone and individuals may differ in either their ability to access these mechanisms or even whether they possess such a mechanism.” Whether or not this is the case, it certainly seems that a sizeable minority, perhaps thirty percent, of “normal” adults may have latent or suppressed savant potentials which may be released to some degree by techniques such as TMS. This is not entirely surprising, given that various pathological conditions— frontotemporal dementia, dominant-hemisphere strokes, certain head injuries and infections— may lead on occasion to the appearance of savantlike abilities.
One must infer that there are, in many individuals, at least, very concrete eidetic and mnemonic powers which are normally hidden, but which may surface or be released under exceptional conditions. The existence of such potentials is only intelligible in evolutionary and developmental terms, as early forms of perception and cognition which once had adaptive value but are now suppressed and superseded by other forms.8
Darold Treffert, who has studied dozens of people with savant powers, both congenital and acquired, emphasizes that there are no “instant” savants, no easy path to savantism. Special mechanisms, whether they are universal or not, may be necessary but not sufficient for savantism. All savants spend years developing and honing their skills, sometimes obsessively and sometimes drawn on by the pleasure of exercising a special skill— a pleasure perhaps heightened by its contrast with their own overall intellectual impairments, or by the recognition and rewards their powers may bring. Being a savant is a way of life, a whole organization of personality, even though it may be built on a single mechanism or skill.
13
An Auditory World: Music and Blindness
When I was growing up in London in the 1930s, I especially enjoyed the visits of Enrico, the piano tuner, who would come every few months to tune our pianos. We had an upright and a grand, and since everyone in the family played, they were always getting out of tune. Once when Enrico was ill, a substitute tuner came— a tuner who, to my amazement, got around without a white stick and could apparently see normally. Up to that point, I had assumed that, like Enrico, all piano tuners were blind.
I thought of this years later in regard to m
y friend Jerome Bruner, for in addition to his many other gifts, he is immensely sensitive to music and possesses extraordinary powers of musical memory and imagery. When I asked him about these, he said that he did not come from a musical family but that he was born with congenital cataracts, not operated on until he was two. He was functionally blind in his first two years, seeing only light and shadow and some movement before his cataracts were removed— and this, he thought, forced him to focus on sounds of all sorts, especially voices and music. This special sensitivity to the auditory has stayed with him all his life.
It was similar with Martin, my musical savant patient, who wore thick pebble glasses like Jerry Bruner; Martin had been born with very severe farsightedness, more than twenty diopters, which was not diagnosed and corrected until he was almost three. He too must have been functionally blind as an infant, before he had glasses. Did this play a part in making him a musical savant?
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THE IMAGE OF the blind musician or the blind poet has an almost mythic resonance, as if the gods have given the gifts of music or poetry in compensation for the sense they have taken away. Blind musicians and bards have played a special role in many cultures, as wandering minstrels, court performers, religious cantors. For centuries, there was a tradition of blind church organists in Europe. There are many blind musicians, especially (though not exclusively) in the world of gospel, blues, and jazz— Stevie Wonder, Ray Charles, Art Tatum, José Feliciano, Rahsaan Roland Kirk, and Doc Watson are only a few. Many such artists, indeed, have “Blind” added to their names almost as an honorific: Blind Lemon Jefferson, the Blind Boys of Alabama, Blind Willie McTell, Blind Willie Johnson.
The channeling of blind people into musical performance is partly a social phenomenon, since the blind were perceived as being cut off from many other occupations. But social forces here are matched by strong internal forces. Blind children are often precociously verbal and develop unusual verbal memories; many of them are similarly drawn to music and motivated to make it central to their lives. Children who lack a visual world will naturally discover or create a rich world of touch and sound.1
At least there are many anecdotes to suggest this, but Adam Ockelford has moved beyond these casual observations to systematic studies in the last twenty years or so. Ockelford has worked as a music teacher at a school for the blind, and is now director of education at the Royal National Institute of the Blind in London. He has been especially concerned with a rare congenital condition, septo-optic dysplasia, which leads to visual impairment, sometimes relatively mild but often profound. Working with Linda Pring, Graham Welch, and Darold Treffert, he compared thirty-two families of children with this condition to an equal number of control families. Half of the children with SOD had no vision or could perceive only light or movement (they were ranked as “blind”); the other half were “partially sighted.” Ockelford et al. noted that there was far more interest in music among the blind and the partially sighted than among the fully sighted. One mother, speaking of her seven-year-old blind daughter, said, “Her music is always with her. If there is not music playing, she is singing. She listens to music while in the car, while falling asleep, and loves to play the piano and any other instrument.”
Though the partially sighted children also showed a heightened interest in music, exceptional musical abilities were observed only in the blind children— abilities that surfaced spontaneously, without any formal teaching. Thus it was not SOD as such but the degree of blindness, the fact of not having a significant visual world, that played a key role in stimulating the musical propensities and abilities of the blind children.
In various other studies, Ockelford found that 40 to 60 percent of the blind children he taught had absolute pitch, and a recent study by Hamilton, Pascual-Leone, and Schlaug also found that 60 percent of blind musicians had absolute pitch, as opposed to perhaps 10 percent among sighted musicians. In normally sighted musicians, early musical training (before the age of six or eight) is crucial in the development or maintenance of absolute pitch— but in these blind musicians, absolute pitch was common even when musical training had been started relatively late, sometimes as late as adolescence.
A third or more of the human cortex is concerned with vision, and if visual input is suddenly lost, very extensive reorganizations and remappings may occur in the cerebral cortex, with the development, sometimes, of intermodal sensations of all sorts. There is much evidence, from Pascual-Leone and his colleagues as well as others,2 to show that in those born blind or early blinded, the massive visual cortex, far from remaining functionless, is reallocated to other sensory inputs, especially hearing and touch, and becomes specialized for the processing of these.3 Even when blindness begins later in life, such reallocation can occur. Nadine Gaab et al., in their study of one late-blinded musician with absolute pitch, were able to show extensive activation of both visual-association areas while he listened to music.
Frédéric Gougoux, Robert Zatorre, and others in Montreal have shown that “blind people are better than sighted controls at judging the direction of pitch change between sounds, even when the speed of change is ten times faster than that perceived by controls— but only if they became blind at an early age.” A tenfold difference here is extraordinary— one does not usually encounter a whole order of magnitude difference in a basic perceptual capacity.
The exact neural correlates underlying musical skills in the blind have not yet been fully defined, but are being intensively studied in Montreal and elsewhere.
In the meantime, we have only the iconic image of the blind musician, the large numbers of blind musicians in the world, descriptions of the frequent musicality of blind children, and personal memoirs. One of the most beautiful of these is the autobiography of Jacques Lusseyran, a writer and hero of the French Resistance who was gifted musically and played the cello as a boy even before being blinded at the age of seven. In his memoir, And There Was Light, he emphasized the immense importance of music for him after he lost his sight:
The first concert hall I ever entered, when I was eight years old, meant more to me in the space of a minute than all the fabled kingdoms…. Going into the hall was the first step in a love story. The tuning of the instruments was my engagement…. I wept with gratitude every time the orchestra began to sing. A world of sounds for a blind man, what sudden grace!…For a blind person music is nourishment…. He needs to receive it, to have it administered at intervals like food…. Music was made for blind people.
14
The Key of Clear Green: Synesthesia and Music
For centuries, humans have searched for a relationship between music and color. Newton thought that the spectrum had seven discrete colors, corresponding in some unknown but simple way to the seven notes of the diatonic scale. “Color organs” and similar instruments, in which each note would be accompanied by a specific color, go back to the early eighteenth century. And there are no less than eighteen densely packed columns on “Colour and Music” in The Oxford Companion to Music. For most of us, the association of color and music is at the level of metaphor. “Like” and “as if” are the hallmarks of such metaphors. But for some people one sensory experience may instantly and automatically provoke another. For a true synesthete, there is no “as if”— simply an instant conjoining of sensations. This may involve any of the senses— for example, one person may perceive individual letters or days of the week as having their own particular colors; another may feel that every color has its own peculiar smell, or every musical interval its own taste.1
One of the first systematic accounts of synesthesia (as this was dubbed in the 1890s) was provided by Francis Galton in his classic 1883 Inquiries into Human Faculty and Its Development— an eccentric and wide-ranging book which included his discovery of the individuality of fingerprints, his use of composite photography, and, most notoriously, his thoughts on eugenics.2 Galton’s studies of “mental imagery” started with an inquiry into people’s abilities to visualize scen
es, faces, and so on in vivid, veridical detail, and then proceeded to their imagery of numbers. Some of Galton’s subjects, to his astonishment, said they invariably “saw” particular numerals— whether they were actually looking at them or even imagining them— in a particular color, always the same color. Though Galton at first thought of this as no more than an “association,” he soon became convinced that it was a physiological phenomenon, a specific and innate faculty of mind with some kinship to mental imagery but more fixed, more stereotyped and automatic in nature, and, in contrast to other forms of mental imagery, virtually impossible to influence by consciousness or will.
Until recently, I had rarely had occasion, as a neurologist, to see anyone with synesthesia— for synesthesia is not something that brings patients to neurologists. Some estimate the incidence of synesthesia to be about one in two thousand, but it may be considerably more common, since most people who have it do not consider it to be a “condition.” They have always been this way, and they assume, until they learn to the contrary, that what they experience is perfectly normal and usual, that everyone experiences fusions of different senses as they do. Thus I have recently discovered, simply by asking, that several patients whom I have been seeing for other conditions, sometimes for years, are in fact synesthetes as well. They had simply never thought to mention it, and I had never asked.