be argued that these two classes of stimuli are uniquely human, making it particularly
relevant to study them in the context of understanding those aspects of brain organization
that are most relevant to human cognition and behaviour. Finally, an overarching theme of
chapters presented in this volume is that music can and should be viewed as a biological
phenomenon, not merely a cultural artifact; from this perspective, therefore, it is not only
meaningful but even imperative to seek out the neural processes that may allow human
beings to engage in the diverse array of behaviours we term music.
All of these considerations set the stage for the studies from my laboratory and from oth-
ers that will be described in this chapter. The recent development of brain imaging tech-
niques, coupled with more traditional behavioural approaches, has allowed for rapid
developments in the field. A great deal of closely related information on music and brain
function is presented in many of the other chapters in this volume, particularly in those by
Besson, Griffiths, Halpern, Pantev, Parsons, Peretz, Samson, Schlaug, and Tervaniemi. The
studies to be discussed in the present chapter focus specifically on aspects of tonal pro-
cessing and their neural substrates. The underlying theme of the research approach is that
by studying these processes we will achieve a more complete understanding not only of the
auditory nervous system, but of the human brain in general. The idea that neural systems
may display functional specializations is generally well accepted in cognitive neuroscience.
The work described in this chapter therefore also has a goal of identifying these specializa-
tions in order to determine the extent to which musical processes depend on dedicated
neural circuitry or may form part of shared neural architecture. In this context, another
important feature of brain organization, hemispheric functional specialization, is also
crucial, and will be important in understanding the pattern that emerges.
In order to make sense of a complex phenomenon such as music, it is necessary, at least
as a starting point, to focus on a specific aspect; in the present set of studies, I have chosen
to explore the processing of pitch, which is to say pitch information as used for musically
relevant processes. This choice is motivated by the fact that pitch appears to be a central
aspect of all music. Although other aspects of music, such as temporal organization for
rhythm, for example, may play an equally important role, it is difficult to conceive of a
musical system of any type that does not involve the patterning of pitches. Moreover, pitch
processing is amenable to study not only because the physical parameters of sounds asso-
ciated with pitch are relatively well understood and easily manipulated, but also because it
affords us the opportunity to analyse different levels of processing. Thus, in what follows I
will consider first of all studies examining relatively low-level aspects of pitch processing,
such as pitch discrimination; second I will discuss higher-order aspects, including pitch
patterns. Finally, I will present some anatomical findings that may be relevant to under-
standing the nature of the functional specializations that the other studies have uncovered.
Basic aspects of pitch processing
To begin, let us consider a relatively simple aspect of a musically relevant function: the abil-
ity to distinguish sounds on the basis of their pitch. The neural basis for the encoding of pitch
has been studied for some time. Indeed, much neurophysiological work both in the periph-
ery and in the central nervous system has examined the processing of frequency information
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