Music
is a universal experience, and for centuries human beings have
engaged with it and wondered at its power. We can now begin to
appreciate how musical forms and structures are related to the
underlying neurological forms and physiological structures that create
them.
There is a new and burgeoning interest in establishing a biological basis for musical experience. Whilst such pure scientific exploration is facilitated by the remarkable recent development of noninvasive brain mapping, it is driven by a powerful urge to understand the mysteries of music. By mapping the structures of the brain that support music we may gain insight into the roots of personal identity and social relationship as well as into the nature of musicality itself.
There is a new and burgeoning interest in establishing a biological basis for musical experience. Whilst such pure scientific exploration is facilitated by the remarkable recent development of noninvasive brain mapping, it is driven by a powerful urge to understand the mysteries of music. By mapping the structures of the brain that support music we may gain insight into the roots of personal identity and social relationship as well as into the nature of musicality itself.
Thirty
years ago, when I first became fascinated in the relationship of music
and brain, any conceptual framework could only be theoretical as
there was then virtually no significant research to call upon.
However, some understanding of the topic did exist, from the observation
of deficits in those who had unfortunately suffered brain lesions,
and there was one excellent book edited by Critchley (Music and Brain,
1977) which gave the scientific views current at that time.
There
was also a vast resource of Philosophy, Psychology and Musical and
Aesthetic theory and, as I discovered when I came to make a television
series on Music and Science (‘Music and the Mind’ Channel 4, 1996),
although mostly unaware of each other, brilliant people were researching
different music-related domains. Since then, there has been a rapid
growth in understanding of how our brains perceive and produce music,
aided greatly by new methods for non-invasively finding our what goes
on inside the human skull..
Whilst these technological advances in brain mapping have undoubtedly moved this topic significantly forward, so has our new culture of inter/intra-disciplinary collaboration and exploration and perhaps the one has driven the other.
Mapping Music
In order
to understand contemporary research it is helpful to have a sense of
what the current technologies make possible and what are their
strengths and limitations.
Basic neuro-anatomy and current brain mapping techniques
The human cerebrum has two broadly symmetrical hemispheres, which in some areas have different but complementary functions. It used to be thought that spoken language and words were solely the province of the left hemisphere whilst music and emotion were located and processed only in the right side of the brain. However, contemporary non-invasive brain mapping techniques reveal a far more complex, interconnected and distributed network of brain areas, which include the evolutionarily older brain areas of the cerebellum and brain stem, which come into play in order to comprehend and discriminate musical sounds.
Mapping Blood Flow Response to Brain Activity
The human cerebrum has two broadly symmetrical hemispheres, which in some areas have different but complementary functions. It used to be thought that spoken language and words were solely the province of the left hemisphere whilst music and emotion were located and processed only in the right side of the brain. However, contemporary non-invasive brain mapping techniques reveal a far more complex, interconnected and distributed network of brain areas, which include the evolutionarily older brain areas of the cerebellum and brain stem, which come into play in order to comprehend and discriminate musical sounds.
Mapping Blood Flow Response to Brain Activity
PET
(Positron Emission Tomography) scans use injected radioactive isotopes
to measure how blood flow varies within the brain. This technique is
silent and can be used to map activity to an accuracy of about 5 mm
during a 2 minute period. Because of the possible risks of over-exposure
only 12 such scans are recommended in a person’s lifetime.
fMRI
(Functional Magnetic Resonance Imaging) measures subtle effects on
water protons which mark blood oxygenation changes associated with
neuronal activity. This technique is very accurate spatially, to about 2
millimeters, and measures reactions over a few seconds, but
unfortunately the scanners make loud noises, which presents obvious,
though not insuperable, problems in the musical domain.
Both PET and fMRI require a good deal of data analysis because the main interest is in the relatively small differences in brain activity relating to specific stimuli.
Electro-physiological measures
EEG
(Electroencephalography) and MEG (Magnetoencephalography) both
directly detect electrical brain activity in real time but require
massive computation because data analysis and comparison are complex.
Neither technique is particularly good at locating where brain
activity is taking place, but they are both able to measure precisely
when it occurred, and to discriminate responses lasting only a few
milliseconds. Because of these technical issues studies usually report
averages of data from a number of subjects rather than individual
snapshots. (illustrate)
A great
deal of fascinating information is generated from studying the exact
timings of electrical activity which can also show positive (P) or
negative (N) surges. These signals generally occur between 100
milli-seconds (ms) to 600 ms and different types of processing have
characteristic profiles.
Much of our best current information comes from the result of combining information from different technical approaches. Irrespective of which approach they favour, the common dedication and passion of all our contributors is to better understand what music is, and why and how we experience it. It is also true to say that everyone working in this field has been touched by music and moved by its mysterious power.
The Science of Music
The
relationship between music and mathematics is as long-standing as that
of music as language. As Leibniz brilliantly observed, ‘Music is the
human mind using mathematics whilst unconscious that it is
calculating’.
For me
this exploration (and our whole current musical science) is based upon
this strange human urge to comprehend events and phenomena, including
the most subjective human experience, as mathematical form. As we
know, the curious intermingling of music and mathematics, and the scores
and symbolic notational systems we use in Western music, are no more
than alternative algorithmic ciphers. Music is after all entirely
constructed from pitches and rhythms which can be mathematically
expressed as variations in sound vibrations over time.
If we
accept the truth of this, then for many of us it is irresistible to
seek to discover not only the algebra of the musical construct but of
the creative imagination, emotion and ‘ineffable’ beauty of musical
inspiration as well. While this might be considered heady stuff, I
suspect this impulse underlies many of these scientists painstaking
research.
Is there
a ‘science’ of meaning or of the emotions? Are these sorties into the
musical hinterland the beginning of such a new science? Could such
‘objective’ explorations demystify music? Or, as many musicians seem to
fear, explain away the ‘magic’ of music? I don’t believe that many (if
any) of our contributors think this either desirable or possible--any
more than learning to play scales ‘explains away’ the beauty of
inspired music, itself constructed of scale combinations.
The
great Russion neuropsychiatrist Luria spoke of his belief in the
evolution of a new ‘Poetic Science’. Perhaps we are seeing this emerging
in music and brain studies As a species, we have been practicing and
refining our musical impulses or ‘instinct’ for thousands of years (at
least 30,000 years judging from early bone flutes). Ancient
civilizations, including the Chinese, Indian and Greeks, studied the
physics of sound, analyzed the mathematics of the harmonic series in
order to construct scales and integrated these theories into their
aesthetics and (often) religious world views.
Since
music plays so fundamental a part of our personal, social and cultural
condition I find myself asking whether our musical constructs are
actually also such ‘maps’ - if we could just decode them. If this is
true then the insights of music-makers would have as great a
contribution to the science of mind and consciousness as can the brain
scientists.
In this context,
Mendelssohn’s profound remark that, ‘Music is too precise to express
in Words’ raises a number of questions. Is music a language? Is it the
foundation of all language? Is music the auditory distillation of the
gestures and pre-linguistic signals of communication and therefore a
proto – or universal language? Does music carry meaning or do we
create a sense of meaning from it because it is essentially ‘semantic’?
or is it somehow a ‘language’ of the emotions? Might we be better
understand our musical experience as a combination of embodied
‘feelings’, cognition and affect? If so, how are they joined? How can
we experience some or all of these at any one time in music? Is music
especially mysterious and potentially ‘meaningful’ because of its
temporal structuring? and so on...
http://www.musicmindspirit.org/
http://www.musicmindspirit.org/
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