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2.5.10.3 Inventario Vial
Apart from efficient auditory and motor skills, dexterous musical performance requires competent visuospatial cognition. Musical sight reading is the ability to read musical notes and translate these notations into movement patterns (Sergent et al., 1992), which is of paramount importance for professional musicians as it influences a musician’s ability to perform a repertoire of rehearsed music. Music reading can be considered as a visuospatial sensorimotor task that involves the visuospatial analysis of symbolic input and the consequent generation of coordinated motor output (Stewart et al., 2003). Interestingly, changing the systematic relationship between the vertical position of a musical note and its corresponding position on the keyboard adversely affected the performance of pianists but not musically naive subjects (Stewart et al., 2004). Regions involved in sight reading ability include the left premotor cortex, Broca’s area (specifically the POP), and superior parietal lobule of both hemispheres (Sergent et al., 1992, Stewart et al., 2003), which were activated when subjects read, listen, and play piano. There is a good evidence that professional musicians perform significantly better than non-musicians in spatial ability tasks. Musicians exhibited better
performance scores than non-musicians in a test of spatial ability, the Benton judgment of line orientation test, which was positively correlated with musicians’ age (Sluming et al., 2002). Sluming and colleagues (Sluming et al., 2007) investigated musicians’ performance on a 3D mental rotation task, which is a complex spatial ability test that involves stimulus identification, mental rotation, and decision making (Shepard and Metzler, 1971). Both musicians and non-musicians showed increased activations in premotor and superior parietal cortices; however, only musicians demonstrated increased activation in Broca’s area. At the behavioral level, it has been shown that musicians, unlike non-musicians, exhibited shorter reaction times when asked to detect the position of a flashed target along the horizontal and vertical planes (Brochard et al.,
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2004, Patston et al., 2007). In support of the aforementioned functional evidence of enhanced visuospatial cognition in musicians, structural studies reported increased size of structures known to support visuospatial cognition, such as increased GM density in the superior parietal lobule (Gaser and Schlaug, 2003b, a) and Broca’s area (Sluming et al., 2002) in professional musicians. Table 2.1 summarizes findings of previous
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Table 2.1. Summary of previous neuroimaging studies comparing musicians and non- musicians.
Motor system
• Increased GM density in Broca’s area in the
dominant hemisphere in male orchestral musicians (
Structural
Sluming et al., 2002).
• Increased GM density in the left inferior frontal gyrus in male and female pianists (Han et al., 2009).
• Increased FA value in the right posterior limb of the internal capsule in musicians (Bengtsson et al., 2005, Han et al., 2009).
• Decreased FA value in the corona radiata and
internal capsule bilaterally in musicians (Schmithorst and Wilke, 2002).
• Decreased FA value in the corticospinal tract in musicians, increased MD in the corticospinal tract in musicians who began training before age of 7 years compared to those who started later and non- musicians (Imfeld et al., 2009).
• Increased total cerebellar volume in male pianists
(Schlaug et al., 1998, Hutchinson et al., 2003).
• Increased GM density in the right cerebellum in
pianists (Han et al., 2009) .
• Musicians had more pronounced omega sign
expression than controls. Keyboard-players had left hemisphere advantage, while string players had right hemisphere advantage (Bangert and Schlaug, 2006).
• Musicians showed greater local variability in the anterior wall of the middle section (somatotopic hand area) of the right central sulcus (Li et al., 2010).
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• Increased intra-sulcal length of the precentral gyrus in the right hemisphere in musicians (Amunts et al., 1997b).
• Increased FA in the central aspect of the cerebellum
in musicians (Schmithorst and Wilke, 2002).
• Reduced cerebellar recruitment in musicians during
bimanual and unimanual motor tasks ( Functional
Koeneke et al., 2004).
• Reduced recruitment of motor association areas
during bimanual (Jancke et al., 2000, Haslinger et al., 2004), and unimanual (Hund-Georgiadis and von Cramon, 1999, Jancke et al., 2000, Krings et al., 2000, Meister et al., 2005) motor tasks in musicians.
Review of Literature
47 Auditory
system • Increased left-sided asymmetry of planum temporale in musicians with absolute pitch ability compared to those who don’t have this ability and non-musicians (
Structural
Schlaug et al., 1995b, Zatorre et al., 1998, Keenan et al., 2001, Luders et al., 2004).
• Increased volume of the anteromedial part of the
Heschl gyrus in musicians (Schneider et al., 2002).
• Fundamental pitch listeners had increased GM
volume of the left lateral Heschl gyrus, whereas spectral pitch listeners had increased GM volume of the right lateral Heschl gyrus (Schneider et al., 2005).
• Increased GM density and cortical thickness in the
posterolateral aspect of the right Heschl gyrus in musicians (Bermudez et al., 2009).
• Increased N-acetylaspartate concentrations in the
planum temporale in musicians (Aydin et al., 2005).
• Increased GM density in the right planum temporale
in musicians (Bermudez and Zatorre, 2005).
• Increased cortical thickness of the right and left planum temporale in musicians (Bermudez et al., 2009).
• Musicians had left hemisphere, while controls have
right hemisphere lateralization of music perception as detected using trans-cranial doppler sonography (
Functional
Evers et al., 1999) and fMRI (Ohnishi et al., 2001, Limb, 2006, Limb et al., 2006).
• Increased auditory cortical representation of piano tones in pianists compared to control subjects (Pantev et al., 1998).
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• Violinists and trumpeters showed evidence of timbre-
specific enhancement of auditory cortical
representation related to instrument specialty (Pantev et al., 2001).
• GM density and cortical thickness in the right Heschl sulcus and bilateral intra-parietal sulci predicted relative pitch task performance in musicians (Foster and Zatorre).
• Musicians had greater right posterior temporal and
supramarginal gyrus activation during a pitch memory task (Gaab and Schlaug, 2003).
• Increased multimodal (auditory-somatosensory)
integration in trumpet players compared to controls (Schulz et al., 2003).
• Evidence of shared auditory-sensorimotor activation
in professional pianists while performing motor task or passive listening (Lotze et al., 2003, Bangert et al., 2006, Baumann et al., 2007).
• Musicians had increased GM density in the left
primary sensorimotor cortex ( Structural
Han et al., 2009).
• Musicians showed greater local variability in the anterior wall of the middle section (somatotopic hand area) of the right central sulcus (Li et al., 2010).
• Increased cortical representation of the digits (second to fifth) of the left hand in violinists (
Functional
Elbert et al., 1995).
• Increased somatosensory cortical representation in
skilled pianists (Pantev et al., 1998).
Somatosensory System
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• Increased GM density of the superior parietal lobule
in professional musicians compared to amateurs and controls (
Structural
Gaser and Schlaug, 2003a).
• Increased GM density in Broca’s area of the left inferior frontal gyrus in orchestral musicians (Sluming et al., 2002).
• Bilateral activation of the visual cortex during verbal memory retrieval task in musicians (
Functional
Huang et al., 2010).
• Increased activation in Broca’s area when performing
a 3D mental rotation (visuospatial) task in musicians (Sluming et al., 2007).
• No significant differences between musicians and
non-musicians in total volumes of prefrontal cortical subfields (
Structural
Sluming et al., 2002).
• Increased cortical thickness of the dorsolateral frontal cortex in musicians (Bermudez et al., 2009).
• Reduced recruitment of the prefrontal cortex during
bimanual motor task in musicians ( Functional
Haslinger et al., 2004).
• Increased activation of the prefrontal cortex during music improvisation in pianists (Bengtsson et al., 2007).
• Involvement of the left dorsolateral subfield of the prefrontal cortex in music processing and perception (Zatorre et al., 1998, Ohnishi et al., 2001) in
musicians with absolute ability but not in musicians
Visuospatial System
Higher cerebral functions/ Prefrontal cortex
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without this ability (Zatorre et al., 1998), and non- musicians (Ohnishi et al., 2001).
• Increased induced gamma-band response, a
measure of attention, expectation, and memory retrieval in adult musicians and after one year of musical training in children musicians compared to non-musicians (Trainor et al., 2009b).
• Increased cross-sectional area of the anterior
(Schlaug et al., 1995a, Ozturk et al., 2002, Lee et al., 2003), and posterior (Ozturk et al., 2002) halves of the midsagittal CC in musicians.
• Evidence of gender versus musicianship interaction
as only male musicians had increased size of the anterior CC (Lee et al., 2003).
• Increased FA in the genu of the CC (Schmithorst and
Wilke, 2002).
• No significant differences between musicians and
non-musicians in FA values in the anterior and posterior halves of the CC (Imfeld et al., 2009).
• Increased FA value of the superior longitudinal
fasciculus in musicians with absolute pitch ability compared to musicians without this ability and non- musicians (Oechslin et al., 2009).
White matter CC
Superior Longitudinal Fasciculus
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2.5 FACTORS GOVERNING USE-DEPENDENT NEUROPLASTICITY IN