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Big Picture: Music, Mind and Medicine

Nov 15, 2014

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Most of us hear some form of music each day. It is a popular leisure activity and accompanies many of the most significant points of our lives.Even so, music remains one of life's great mysteries. How can it have such a powerful impact? And what exactly is music? FInd out in this free educational publication. 'Big Picture' is a free post-16 resource for teachers that explores issues around biology and medicine.

PictureBigISSUE 10 JUNE 2009BRINGING CUTTING-EDGE SCIENCE INTO THE CLASSROOMFREEresource for teachersMUSIC, MINDAND MEDICINE Music and emotionsEvolution of musicMusic and medicineCreativity and musicMoved by musicHow music affects mind and bodyAlexandru/Shutterstock2 Big Picture 10: Music, Mind and MedicinePictureBigBig Picture on musicIt is hard to imagine a world without music. Most of us hear some form of music every day. It is a popular leisure activity and it accompanies many of the most signicant points of our lives: our infancy, our marriages, our funerals. It is a powerful trigger of emotional memories. Often, we can tell the story of our lives in songsand music.Even so, music remains one of lifes great mysteries. How can it have such a powerful impact on us? What exactly is it for? When in human history did it appearand why? Do other animals experience music?And what exactly is music anyway? Harmony in my head Magical mystery tourMusic always involves combinations of pitch, timbre, rhythm, loudness, tempo, melody and harmony. These elements can be combined to create a huge diversity of music from African drumming to Johann Sebastian Bach, Inuit throat singing to Razorlight. Its a beautiful noisePITCH:How high or low a note is. Linked to the frequency of a sound waveTONE:A regular sound of distinct pitch; musical systems are based on a discrete set of tonesOCTAVE:Musical interval of eight full tones (e.g. from C to the C above it), over which pitch frequency halves or doublesTIMBRE:Why the same note on a trombone sounds different to one playedon a violinRHYTHM:The organisation of musical stressesover timeHARMONY:Combining notes of different pitches to create new soundsLOUDNESS:The volume of sound. Dependent on the amplitude of a sound waveTEMPO:The speed at which a piece of music is playedMELODY:A pleasing arrangement of notesIn the inner ear, the cochlea converts sound waves into the language of the brain: nerve impulses. Within the organ of Corti, tiny hair cells in the basilar membrane detect sound vibrations. Inner hair cells convert mechanical stimulation to an electrical signal. Their deformation opens ion channels, triggering a series of cellular events that ultimately generates an action potential in the auditory nerve.Because of the structure of the basilar membrane, different parts of the cochlea respond to sounds of different pitch. At one end the membrane is narrow and stiff and vibrates in response to high pitches. The other end is wider and more exible, responding to deeper sounds.But information doesnt just ow one way. The brain can send signals that sharpen up responses of hair cells, so we can concentrate on specic aspects of sound in complex environments. www.wellcome.ac.uk/bigpicture/musicSOUND AND VISIONThe sound journey from ear to brain is summarised at Big Picture Online. See how the cochlea is beautifully structured to detect sound and transmit information to the brain.The website also includes an audio library providing auditory material to complement the articles in this issue.ON THE WEBsystems are based on a discrete set of tonesto the C above it), over which pitch frequencyhalves or doublesoDtaJUNE 2009 3How are music and language related?Music and language have much in common. Both depend upon the brains perception of structured sound input. Links between the two were noted by the ancient Greeks, and Charles Darwin speculated about how they might be related. During the 20th century, attention focused mainly on their differences, with the idea that the brain had specic modules for decoding music, distinct from those that handled language.In reality, the lines between language and music are not always clear cut. Talking drums, usedto send messages in parts of Africa, and the whistling languages of Africa, Asia and South America resemble music but convey information as normal languages do. Baby talk (the cooing intonation of mothereseor parentese) also blurs the boundaries.Similarly, the idea that there are separate music-processing areas in the brain has been challenged. Localised brain damage can affect specic aspects of music perception, but often disrupts both music and language. An emerging idea is that there are brain networks and areas for music that overlap with, but are not identical to, those used in language. So which came rst? Did early humans chat or sing round the campre? One possibility is that rhythm and early motherese-like communication provided a common foundation for both language and music. The two diverged as language became the principal tool of communication, with well-dened structures and rules. Music set off in a different direction. Yet their common ancestry lives on in the shared processing pathwaysin our brains. Always on my mindOur brains recognise octaves as special. Happy Birthday is a well-known tune, written surprisingly recently (technically, it is still in copyright). As with all songs, if its notes are all raised by an octave (or multiple octaves) it remains instantly recognisable. A much smaller shift in frequency, if it does not match an octave, has a much more dramatic impact on melody and makes the tune harder to spot.Remarkably, our brains have an innate ability to spot the fact that notes an octave apart are the same. This capacity is even present in unborn infants, whose heart rate changes when they experience novel sounds. An octave shift, though, has a relatively small effect on heart rate.Perhaps even more remarkably, other primates share this ability. Rhesus monkeys trained to distinguish same from different can spot the similarity between different versions of Happy Birthday (and other simple songs) but only when they are played an octave apart.Early music was passed on from person to person. Oral tradition remains the norm in many regions, including most of Africa. Generally, though, some form of musical notation is used. The ancient Greeks wrote melodies as lines of letters. But it wasnt until eighth-century Church music that changes in pitches were shown: diagonal lines indicated rises or falls in the tune. More precise changes in pitch were written in the tenth century, when a single line represented a xed tone and pitch varied above or below this by set distances. By the 12th century, staves had four lines with pitches on alternate spaces and lines. We now have ve.In Japanese music there is no consensus notation because the music is so diverse. The notation for the Shakuhachi bamboo utes is pictorial: a symbol for each note with dots and lines for lengths and intonation. Talking loud and clearAn African talking drum.EXPECTANCY,CONTEMPLATIONConsonance/dissonance Tempo change VISUAL PERCEPTION Performer Dancer Music reading PERSONALITY AND PREFERENCE Taste Subcu|tureSENSORY ANALYSIS Foot tapping SingingEMOTIONS Fee|ings (joy etc.}Physica| sensations (goosebumps etc.)AUDITORY PROCESSING Pitch Rhythm Harmony Lyrics Timbre etc. MEMORYAssociation with past eventsAbacabBrain imaging shows that music perception involves a wide range of brain regions. Many are specialised: music evoking happiness and joy, for examp|e, leads to increased activity in a network including the evolutionarily ancient emotional areas of the brain.The experiences of peop|e with brain damage, often from injury or stroke, te|| us about how the brain understands music. For examp|e, people with damage to a particular region on the right side of the brain can no longer tell whether a pitch changes to a higher or lower note. As a result they cannot perceive a tunes ups and downs over time its melodic contour. There is overlap between music perception and other brain functions, particularly music and language. For examp|e, anoma|ous or unexpected events in both music and language are detected by similar brain regions.The brain has a complex interconnected set of pathways for processing music.Wired for soundPhotodiscA Tibetan musical score from a Buddhist monastic ritual, circa late 18th19th century.PictureBig4Big Picture 10: Music, Mind and MedicineEmotions are associated with activityin a network of brain structures. Music is very good at stimulating activity in these areas a sign of the tremendous emotional impact of music.Interestingly, emotional reactions seem to be an innate aspect of music perception. Dissonance, combinations of notes that clash with one another, is distressing. The phenomenon is often exp|oited by composers. a contro||ed change from dissonant to consonant tones is appreciated as a resolution of tension in diverse cultures from Hinduto Western.The Devils interval two notes three tones apart (e.g. a C and an F sharp), played simultaneously or one after another automatically induces a feeling of dread. In medieval times it was considered evil and banned. More recently, it has been a staple of horror lms and heavy metal (though it also appears in West Side Story and the theme to The Simpsons).The |ink with emotions a|so exp|ains why music is so good at conjuring up memories. In particular, one region of the prefronta| cortex responds both to fami|iar music and autobiographical memories (those most relevant to us as individuals). Listening to a song heard on a rst date can thus call up powerful recollections of excitement (or embarrassment}.Interestingly, this is one of the last areas to be lost in Alzheimers disease, suggesting that music could help people to retrieve personal memories even at late stages of disease. Heartbeat Music can trigger powerful physiological responses.Music can elicit a remarkable range of emotions, from elation to the deepest sorrow. As well as provoking a mental response, it also has characteristiceffects on the body. Music can give us the thrills, chills and shivers. Heart rate and skin conductance may change. The hairs on the back of our neck (and elsewhere) really do stand up. These effects arise from the action of hormones, triggered by signals from structures such as the hypothalamus. Stirring, martia