The Cognitive Neuroscience of Music

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Figure 24.2(A) The intrasulcal length of the posterior bank of the precentral gyrus (ILPG) was measured in hori-
zontal slices (parallel to the AC–PC plane) from the deepest point of the central sulcus following the contour line of
the precentral gyrus to a lateral surface tangent that connected the crests of the pre- and postcentral gyrus. (B and C)
We differentiated a dorsal and a ventral subregion. The dorsal subregion roughly corresponds to the location of the
functional hand motor area. We found prominent differences in the intrasulcal length of the precentral gyrus in the
dorsal subregion between musicians and nonmusicians. Musicians had more symmetrical lengths which was due to a
disproportional increase in length of the nondominant hemisphere. (See Plate 21 in colour section.)

Horizontal position (talairach coordinate z)

Dorsal

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6

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0

• 2
  A

A C

B

B

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  Difference between left and right intrasulcal length (mm) 65 60 55 50 45 40 35

Ventral

Right>Left

Left > Right

A

B

Musicians

Nonmusicians

∗) CS

Figure 24.3Significant correlations between age of commencement of musical training and the intrasulcal length
of the right and left precentral gyrus which was chosen as a marker of primary motor hand area.

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25

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ILPG, Right hemisphere (mm)23 4

ILPG, Left hemisphere (mm)

567891011 234567891011

Age of commencement (years) Age of commencement (years)

capillaries) after long-term motor activity and motor skill acquisition. These findings com-
bined with the role of the cerebellum in movement coordination, timing of sequential
movements, and possibly other cognitive functions,^49 lead us to examine whether the cere-
bellum of adult musicians differs structurally from those of nonmusicians.^12 From a