Mind, Body, World- Foundations of Cognitive Science, 2013a

function that is inconsequentially related to other modular processes. “Music is
auditory cheesecake, an exquisite confection crafted to tickle the sensitive spots of
at least six of our mental faculties” (p. 534).
Not surprisingly, researchers interested in studying music have reacted strongly
against this position. There is currently a growing literature that provides support
for the notion that musical processing—in particular the perception of rhythm and
of tonal profile—is indeed modular (Alossa & Castelli, 2009; Peretz, 2009; Peretz
& Coltheart, 2003; Peretz & Hyde, 2003; Peretz & Zatorre, 2003, 2005). The types of
evidence reported in this literature are good examples of the ways in which cognitive
neuroscience can defend claims about modularity.
One class of evidence concerns dissociations that are observed in patients who
have had some type of brain injury. In a dissociation, an injury to one region of
the brain disrupts one kind of processing but leaves another unaffected, suggesting
that the two kinds of processing are separate and are associated with different
brain areas. Those who do not believe in the modularity of music tend to see
music as being strongly related to language. However, musical processing and language
processing have been shown to be dissociated. Vascular damage to the left
hemisphere of the Russian composer Shebalin produced severe language deficits
but did not affect his ability to continue composing some of his best works (Luria,
Tsvetkova, & Futer, 1965). Reciprocal evidence indicates that there is in fact a double
dissociation between language and music: bilateral damage to the brain of another
patient produced severe problems in music memory and perception but did not
affect her language (Peretz et al., 1994).
Another class of evidence is to seek dissociations involving music that are related
to congenital brain disorders. Musical savants demonstrate such a dissociation:
they exhibit low general intelligence but at the same time demonstrate exceptional
musical abilities (Miller, 1989; Pring, Woolf, & Tadic, 2008). Again, the dissociation
is double. Approximately 4 percent of the population is tone deaf, suffering from
what is called congenital amusia (Ayotte, Peretz, & Hyde, 2002; Peretz et al., 2002).
Congenital amusics are musically impaired, but they are of normal intelligence
and have normal language abilities. For instance, they have normal spatial abilities
(Tillmann et al., 2010), and while they have short-term memory problems for musical
stimuli, they have normal short-term memory for verbal materials (Tillmann,
Schulze, & Foxton, 2009). Finally, there is evidence that congenital amusia is genetically
inherited, which would be a plausible consequence of the modularity of musical
processing (Peretz, Cummings, & Dube, 2007).
A third class of evidence that cognitive neuroscience can provide about modularity
comes from a variety of techniques that noninvasively measure regional
brain activity as information processing occurs (Cabeza & Kingstone, 2006;
Gazzaniga, 2000). Brain imaging data can be used to seek dissociations and
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