Music and the Mind. Anthony Storr

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      In most cases of musicogenic epilepsy, the seizures are induced by music played by an orchestra. Less commonly, a single instrument, piano, organ, or the ringing of bells may cause an attack. In very rare instances, even the recall of music can be sufficient provocation. Musicogenic epilepsy raises many unsolved neurological problems which it would be inappropriate to discuss in this context. But this rare phenomenon convincingly demonstrates that music has a direct effect upon the brain.

      Music and speech are separately represented in the two hemispheres of the brain. Although there is considerable overlap, as happens with many cerebral functions, language is predominantly processed in the left hemisphere, whilst music is chiefly scanned and appreciated in the right hemisphere. The division of function is not so much between words and music as between logic and emotion. When words are directly linked with emotions, as they are in poetry and song, the right hemisphere is operative. But it is the left hemisphere which deals with the language of conceptual thought. This difference between the hemispheres can be demonstrated in a variety of ways.

      It is possible to sedate one hemisphere of the brain whilst leaving the other in a normal state of alertness. If a barbiturate is injected into the left carotid artery, so that the left hemisphere of the brain is sedated, the subject is unable to speak, but can still sing. If the injection is made into the right carotid artery, the person cannot sing, but can speak normally. Stammerers can sometimes sing sentences which they cannot speak; presumably because the stammering pattern is encoded in the left hemisphere, whilst singing is predominantly a right hemispheric activity.

      The electrical activity of different parts of the brain can be recorded by means of the electro-encephalogram. It can be demonstrated that, if recordings of speech are played to six-month-old babies, the left hemisphere of the brain will show more electrical activity than the right. But if recordings of music are played, the right hemisphere shows the greater electrical response.

      If different melodies are played simultaneously through right and left earphones (so-called ‘dichotic listening’), the melody heard through the left earphone will be better recalled than that heard through the right. This is because the left ear has greater representation in the right hemisphere of the brain. The right hemisphere processes the perception of melody more efficiently than the left. If words are similarly presented, the reverse is true since the left hemisphere specializes in processing language.

      Patients who have suffered brain damage or disease may lose the ability to understand or make use of language without losing musical competence. The great Soviet neuro-psychologist A. R. Luria studied a composer named Vissarion Shebalin who, following a stroke, suffered from severe sensory aphasia; that is, he was unable to understand the meaning of words. Yet he continued to teach music and composed his fifth symphony which Shostakovich said was brilliant.²⁰ Luria’s famous patient, Zasetsky, whom he studied for many years, received a terrible bullet wound during the Second World War which extensively damaged the left side of his brain. His capacity to use and understand language was at first badly impaired. Amongst many other losses of cerebral function, his spatial perception was grossly distorted and his memory fragmented. Yet he liked music just as much as he had done before he was wounded, and could easily remember the melodies of songs, though not their words.²¹

      Howard Gardner reports the case of an American composer who suffered from a form of aphasia which left him with a persistent reading difficulty. But, although he could not understand the meaning of printed words, he had little difficulty with musical notation, and was able to compose music just as well as he could before his aphasia.²²

      The musician portrayed in Oliver Sacks’s The Man Who Mistook His Wife for a Hat suffered from a brain lesion which, although he could see, made it impossible for him to recognize the essential nature of objects, as the title of the book indicates. Yet his musical abilities were unimpaired: indeed, he could only dress himself, eat a meal, or have a bath, if he did so whilst singing. Music became the only way by which he could structure the external world or find meaning in it.²³ This case might be illuminatingly compared with that of the autistic boy, David, described earlier.

      There are very few instances of brain lateralization in other animals, although, interestingly enough, bird-song is one exception. In birds, a functioning left hypoglossal nerve is essential for the production of song.

      The development of hemispheric specialization is certainly connected with the development of language as an uniquely human phenomenon. Moreover, language is not only a superior means of communication between human beings, but also an essential tool for understanding and thinking about the world. We do not necessarily think in words. The scanning and sorting of information goes on unconsciously as part of the creative process, and can certainly take place during sleep. There is no reason to confine the use of the term ‘thinking’ to conscious deliberation. But, if we are to formulate our thoughts, express them, and convey them to our fellows, we must put them into words. Although language appears to be understood by both hemispheres to some extent, formulating thoughts in words, and creating new sentences, are functions of the left hemisphere.

      It is worth noting that children with lesions in the right hemisphere may be competent at reading, but poor at communicating their feelings. Their speech is often monotonous and inexpressive, lacking just those emotional/intonational aspects of speech recognized earlier as being important in communication between mothers and infants.

      It is probably the case that as a listener to music becomes more sophisticated and therefore more critical, musical perception becomes partly transferred to the left hemisphere. However, when words and music are closely associated, as in the words of songs, it seems that both are lodged together in the right hemisphere as part of a single Gestalt. Since the word order of a song is fixed, the innovative verbal skills which belong in the left hemisphere are not required.

      Musical gifts are multiple and not always found together in the same person. There is often a wide discrepancy between musical interest and musical talent. Many of those to whom music is immensely important struggle for years to express themselves as composers or executants without avail. Others who are auditorily gifted, as shown by musical aptitude tests, are not necessarily very interested in music. Teachers of music agree that enthusiasm for music becomes increasingly important for success as a child grows older. Musically gifted children may fail to realize their full potential because their interest in music declines.²⁴

      It is my impression, and no more than an impression, that this discrepancy between interest and talent is more often encountered in music than in other subjects. For example, those who are not mathematically gifted seldom long to be mathematicians; but musical enthusiasts often confess that their lack of musical talent is their greatest disappointment.

      The discrepancy between interest in, and talent for, music may be explicable in terms of hemispheric specialization. We have already observed that critical appreciation of music is partly a function of the left hemisphere. People who score highly on a test of musical aptitude tend to show left hemisphere advantage, regardless of training.²⁵ Perhaps emotional response to music is chiefly centred in the right hemisphere, whilst executive skills and critical analysis are functions of the left hemisphere. Sloboda quotes the case of a violinist with damage to the left hemisphere who retained some musical abilities whilst suffering impairment of others. A great deal of further research is required to establish the neurological correlates of the varied skills which music requires, but what seems certain is that there is no one centre in the brain which houses them all.

      As we pointed out earlier, the language used both by philosophers and scientists is neutral and objective. It eschews the personal, the particular, the emotional, the subjective. No wonder it is principally housed in a separate part of the brain from that concerned with the expressive aspects of music. Whilst it is perfectly possible to study music from a purely objective, intellectual point of view, this approach alone is insufficient.

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