360 contrast, location and movement of sounds are determined in more posterior aspects of
the STG.27,29,30The latter regions project to the posterior parietal cortex,^31 also known to
be involved in auditory spatial processing, as mentioned above.18,34,35Anterior STG
projects to orbitofrontal cortex, which plays a role in working memory for objects,^36
whereas the caudal STG projects to dorsolateral prefrontal cortex, directly and via parietal
cortex, again highly consistent with its role in spatial processing.^37Musical learning and auditory imagery
If the anterior STG and orbito-frontal cortex are responsible for the processing of complex
auditory ‘images’, patterns, or objects, they should also be the storage houses of musical
memories. Indeed, when we try to imagine music, we activate parts of the auditory cortex
that is anterior to Heschl’s region (primary auditory cortex) plus areas in frontal cortex.^38
Even when we simply anticipate familiar music, inferior frontal cortex lights up.^39 This may
correspond to the involvement of left frontal regions in the retrieval of complex memories,
as predicted in a model put forward by Tulving and coworkers.^40 Other brain regions, such
as the cerebellum and the anterior cingulate cortex, are also active during anticipatory
imagery of music (Figure 23.4). This justifies the idea that mental rehearsal, by activating
some of the same brain regions as during a real performance, helps to practice and mem-
orize music, even though we do not actually play the instrument at that time. It is also well
known that professional conductors are not only able to conduct hundreds of pieces from
memory but also rehearse them mentally, stressing again the partial equivalence of brain
activation through attention and mental exercise.
‘What’ and ‘where’ information in music come together for conductors of large orches-
tras. In these situations, the content of what is being played is of utmost importance, butFigure 23.3 Auditory cortical activation while listening to music. Averaged group results of functional magnetic
resonance imaging are shown. While the processing of music by the right cerebral hemisphere has often been
emphasized^32 (as opposed to language, which is thought to be processed primarily on the left), it is now generally
accepted that different aspects of music are processed by bothhemispheres.^33 (See Plate 19 in colour section.)