Article

No disadvantage forleft-handed musicians:
The relationshipbetween handedness,
perceived constraints
and performance-related
skills in string players
and pianists

Psychology of Music40(3) 357–384© The Author(s) 2011
Reprints and permission: sagepub.co.uk/journalsPermissions.nav
DOI: 10.1177/0305735610394708
pom.sagepub.com

Reinhard Kopiez

Hanover University of Music, Drama and Media, Hanover Music Lab, Hanover, Germany

Hans-Christian Jabusch

University of Music “Carl Maria von Weber”, Institute of Musicians’ Medicine, Dresden, Germany

Niels Galley

University of Cologne, Institute for Psychology, Germany

Jan-Christoph Homann

Hanover University of Music, Drama and Media, Institute for Music Physiology and Musicians’ Medicine,
Hanover, Germany

Andreas C. Lehmann

University of Music, Würzburg, Germany

Eckart Altenmüller

Hanover University of Music, Drama and Media, Institute for Music Physiology and Musicians’ Medicine, Hanover,Germany

Corresponding author:
Reinhard Kopiez, Hanover University of Music, Drama and Media, Emmichplatz 1 30175 Hanover, Germany.
[email: reinhard.kopiez@hmtm-hannover.de]358

Psychology of Music 40(3)Abstract
Two studies investigate the influence of handedness on a musical performance. In Experiment 1 wecompared designated non-right-handed (dNRH) and designated right-handed (dRH) string and piano
players performing in the (non-inverted) standard playing position with respect to (1) performancerelated variables (e.g., musical expression) and (2) health-related variables (e.g., discomfort). The 47
professional instrumentalists (pianists: n 23, string players: n 24) were classified for handedness(performance handedness) and participated in a survey study on sensorimotor skills and theirsense of well-being at the instrument. In Experiment 2, we tested for differences in sensorimotor
performance of both hands in right- and left-handed pianists: 19 professional pianists (music
students) were classified for handedness (preference handedness). Participants performed scaleplaying. In Experiment 1 no evidence was found for a performance-related or well-being-related
disadvantage in dNRH instrumentalists playing in the standard position. In Experiment 2 temporal
sensorimotor precision in the right hand was superior to that of the left hand in both right- and lefthanded pianists. We conclude that professional musicians adapt to the standard playing position
regardless of their objective handedness. However, it cannot be ruled out that a subgroup of dNRH
instrumentalists subjectively feel constricted when playing in the standard position.

Keywords
handedness, music performance, pianists, sensorimotor skills, string players

This study investigates a widely neglected yet important aspect of music performance: namely
handedness, and how it may affect performance skills in string players and pianists. In two
experiments we examined whether non-right-handed instrumentalists experience a disadvantage in instrumental performance and bodily well-being by their handedness when performing
on an instrument intended for right-handers. This study is meant as a contribution to theresearch concerning the relationship between handedness, bimanual training and music
performance.
In recent years, musical performance research has found evidence for the relevance of neurobiological factors for music-related sensorimotor achievement. For example, speed of information processing plays an important role in the unrehearsed performance (so-called “sightreading”) from a musical score (Kopiez & Lee, 2006, 2008; Lehmann & Kopiez, 2009). As
another neurobiological factor, handedness in terms of cerebral asymmetry or “cerebral dominance” (Annett, 2002, p. 6) seems to be relevant for sensorimotor achievement in instrumentalists. For example, in exercising a musical sub-skill, the unrehearsed performance of music,
pianists with a tendency to ambidexterity showed an improved performance of about 22%compared with right-handed pianists (Kopiez, Galley, & Lee, 2006).
In our study, we refer to handedness as the “functional asymmetry” of hemispheres which
can be identified by the measurement of performance differences between hands in a standardized task (see Preilowski, 2005). As long as there are no reliable methods for the analysis of thegenetic handedness, the measurement of performance handedness seems to be an objective
approach for determining functional brain asymmetry (for an extensive discussion of this point
see Kopiez, Galley, & Lehmann, 2010). The role of sensorimotor practice in the neuroplasticityof the musician’s brains has also been considered in recent research. For example, PascualLeone et al. (1995) demonstrated by means of two-hour daily practice sessions of a one-handed
five-finger piano exercise over five days that the acquisition of new fine motor skills was accompanied by immediate cortical reorganization in the respective motor areas. Using transcranial
magnetic stimulation (TMS), they observed a decrease of the activation threshold for the long
finger extensor and flexor muscles of the trained hand already after two days of practice, which

Kopiez et al.

359

continuously decreased until day five. The authors concluded that acquisition of motor skills
was associated with a modulation of the cortical motor outputs in the muscles involved in thetask. They assumed that the extended practice unmasked pre-existing, but unused, synaptic
connections. Elbert, Pantev, Wienbruch, Rockstroh, and Taub (1995) demonstrated long-term
plasticity effects of extensive motor training. They investigated the cortical representations of
the left-hand digits of string players and found larger representations in musicians comparedwith non-instrumentalists. The dipole moment (as an indicator of total neuronal activity) forthe left little finger increased with the decreasing age at instrumental commencement. Bangert
and Schlaug (2006) observed the so-called “Omega sign” (a gross anatomical structure in theprecentral gyrus associated with hand movement representations) in right-handed string players and pianists. The visual salience of the Omega sign was greater in the right hemisphere ofstring players as compared with the left hemisphere. The reversed pattern was observed in pianists. For string players, results were interpreted in terms of an adaptation effect due to highdemands of sensorimotor control (intonation, vibrato, etc.) in the left hand. In contrast, piano
literature is dominated by higher demands on the right hand in general, resulting in a moreleft-hemispheric prominence of the Omega sign. This seeming contradictory to the findings ofAmunts et al. (1997), who observed a more symmetrical intrasulcus length of the precentral
gyrus (ILPG; as a measure of the size of the primary motor cortex) in professional pianists, canbe explained by a group inhomogeneity in the Amunts et al. study: nine out of 21 right-handed
pianists also played string instruments. Although Amunts et al. (1997) interpreted their findings in terms of a structural adaptation effect (which increases with decreasing age at the commencement of instrumental training), they could not rule out a selectional effect for the ILPG
differences (p. 212), which means that an individual could become a skilled musician due to hislarger motor cortex. The relevance of intensive bimanual training for the general effect of areduced degree of hand skill asymmetry in pianists, as, for example, observed by Jäncke,
Schlaug, and Steinmetz (1997), is still under discussion, and a final answer could only be given
by a longitudinal study on the relationship between functional asymmetry and early commencement of instrumental training (see Kopiez et al., 2010).
Against the background of the current state of handedness research, Annett (2002) posited, however, that “years of practising scales with both hands may not remove the superiorityof the preferred hand, whether right or left” (p. 18). In other words, the chicken-or-egg question of what comes first, the preference for one hand (which is strengthened by practice) or the
performance advantage of one hand (which is extended by sustained practice), can currently
be considered in light of the performance hypothesis. In experiments consisting of long-term
speed tapping practice over a couple of weeks for both the preferred and non-preferred hand,both hands showed improvement in tapping speed through practice, but the relative magnitudeof the between-hand performance difference remained stable for most subjects (Peters, 1981).
This view of functional asymmetry of hand movement differences as a prerequisite for,rather than a consequence of, handedness is supported by a few neurobiological reports; however, the picture is equivocal. Using magnetoencephalography (MEG), Volkmann, Schnitzler,
Witte, and Freund (1998) showed that individual asymmetry in hand motor performance (asmeasured by a hand dexterity test) covaried with the asymmetry of the hemispheric hand area
size of the primary motor cortex. Significant group differences between right- and left-handers
revealed a stronger leftward asymmetry of hand motor representations for right-handers andvice versa. The authors argued that this expansion of hand motor cortex in the dominant hemisphere may provide extra space for encoding greater motor skills of the preferred hand, andthey suggested that it is more likely a prerequisite for than a consequence of handedness. Using
magnetic resonance imaging (MRI) Klöppel, Mangin, Vongerichten, Frackowiak, and Siebner

360

Psychology of Music 40(3)(2010) investigated the sulcal surfaces in consistent adult right- and left-handers and in adult“converted” left-handers who had been forced to become dextral writers in childhood. In consistent right- and left-handers, they found an interhemispheric asymmetry in the surface areaof the central sulcus with a greater surface contralateral to the dominant hand. This pattern
was reversed in the converted group which showed a larger surface of the central sulcus in
their left, non-dominant hemisphere. The authors concluded that this finding in converted lefthanders indicated plasticity of the primary sensorimotor cortex as a consequence of forced useof the non-dominant hand.
If, as shown by Volkmann et al. (1998), the degree of performance asymmetry between
hands is a reliable indicator of lateral asymmetry, the questions remain if handedness influences motor learning and if it is perhaps influenced through learning itself. The current stateof research shows an ambiguous picture: in an early review, Provins (1967) discussed theanthropological foundations of human motor behaviour (in terms of spatio-temporal movement patterns) and concluded that there must be a hereditary as well as an environmental
basis for the asymmetry in human preferential hand usage. The author assumed that training
plays a crucial role in the development of handedness and that the differential development ofskill asymmetry depends on previous experience. However, Cho, Park, Kim, and Park (2006)
demonstrated that skill learning (as measured by a repeated tracking task) was not correlatedwith the degree of hand performance asymmetry in a speed tapping task (as an indicator of
handedness) and argued that handedness might not directly influence skill learning. However,the simplicity of their motor task and the restriction to right-handed subjects only limits thevalidity of their conclusion. More convincing support for the assumption of a general advantage of non-right-handedness in complex motor tasks was given by Judge and Stirling (2003):
left-handers (classified by a preference handedness inventory and the writing hand as an additional criterion) outperformed right-handers in a bimanual assembly task with alternating
hands (Purdue pegboard test). Our re-analysis of means revealed a medium effect size (Cohen’s
d 0.6). In regard to music-related motor tasks, there is some evidence that non-right-handedmusicians have a sensorimotor advantage over right-handed musicians in selected instruments. For example, in a survey study, Christman (1993) observed weaker degrees of lateralization in players of instruments requiring temporally integrated bimanual motor activity (e.g.,
strings and woodwinds), as opposed to those instruments requiring more independent motor
control (e.g., keyboard instruments). He assumed that ambidexterity could be beneficial for“integrated” instruments with a higher demand of bihemispheric sensorimotor control. In
regard to instrumental creative achievement, Christman (2010) argued, using the example of
Jimi Hendrix, that ambidexterity in terms of greater hemispheric intereaction could be beneficial for the sensorimotor integration of the roles of left and right hands in guitar playing andthe writing of lyrics (for more information on left-handed guitar players see Engel, 2006).
Finally, non-right-handed subjects seem to have an advantage in selected music-related perceptual tasks. As Deutsch (1978) showed, moderately left-handed subjects were superior in apitch memory task. A re-analysis of her results revealed a medium effect compared to the performance of strongly left-handed (Cohen’s w 0.28; see Cohen, 1988), and strongly righthanded persons (Cohen’s w 0.34) and a medium to large effect compared to the performanceof strongly left-handed, and moderately right-handed subjects (Cohen’s w 0.45). The superiority of moderate left-handers was explained in terms of a duplication of representation ofpitch information in both hemispheres, resulting in a more efficient retrieval of informationfrom two separate loci and an increased overall probability of correct judgment. Perceptual differences between the right and left ear in right- and non-right-handers in a hearing task wereKopiez et al.

361

also observed by Dane and Gümüstekin (2006). When subjects had to indicate the fade away ofa test tone, right-handers showed a longer hearing duration for the right ear (large effect,
Cohen’s d 0.9) and non-right-handers for the left ear (small effect, Cohen’s d 0.2). These
results are in line with the assumption of handedness-specific advantages in auditory processing by Deutsch (1978).
In contrast to the aforementioned studies, some musical practitioners claimed that lefthanded instrumentalists playing in a standard position might experience disadvantages, suchas reduced musical expressivity, well-being and motor control (e.g., Mengler, 2004). Jäncke etal. (2006) reported on a left-handed professional pianist, who initially learned to play on aregular piano but, at a point in his professional career, switched to a reversed keyboard. Twothirds of the time he played on reversed pianos, both for professional recordings and international performances. Laeng and Park (1999) compared the correctness of notes in piano
playing of left-handed and right-handed amateurs, whose average keyboard training was two
years, and novices. Subjects played simple scores (with a fast-moving melody in the right handand a slow-moving accompaniment in the left hand) on a normal keyboard and inverted scores(with the fast-moving melody in the left hand) on a reversed keyboard. While both right-handedgroups and the left-handed amateurs performed better on the normal keyboard (with the normal score), the left-handed novices performed better on the reversed keyboard (with the inverted
score). The authors concluded that right-handed keyboards may well be an inept tool for thehands of left-handers.
On a more anecdotal level, early attempts to construct pianos with inverted keyboards weremade already in the 19th century. For example, the Russian pianist and composer Joseph
Wieniawski tried to stimulate the construction of inverted keyboards for left-handed pianists.
In the 20th century, the left-handed German-Hungarian pianist Geza Loso felt constrained in
his musical expressivity playing on a standard keyboard and decided to continue his career ona grand piano with an inverted keyboard. As he stated, “Geza Loso hopes that left-handed piano
students may one day express their music abilities with the hands they are born with.” (Loso,2004) However, Loso’s engagement for left-handed pianists has also been determined by commercial interest: as the owner of a publishing company for left-handed piano scores, he holds apatent on left-handed pianos. (For more details on the historical background of inverted instruments see also Kopiez & Galley, 2010.)
To summarize, from a scientific perspective, although there seems to be a slight advantage, it
is not quite clear whether non-right-handedness is generally advantageous or disadvantageous
for sensorimotor expert performance on a bimanually played instrument. However, from theperspective of musical practitioners, the question has yet to be answered whether there ispotentially a general disadvantage for non-right-handed expert musicians playing in the standard position.

Rationale of the study and hypotheses
The aim of our study was to answer the question of whether playing in the standard position is
disadvantageous for non-right-handed instrumentalists. The critical point is the operationalization of the dependent variable, “disadvantage”. Thus, we employed two complementary
approaches in our study: (1) On a subjective level we asked right- and non-right-handed string
and piano players to rate their contentment with their expressive and technical skills, and to list
the frequency of bodily discomfort (Experiment 1); (2) on an objective level we measured theperformance skills of the dominant and non-dominant hands in right- and left-handed pianists

362

Psychology of Music 40(3)in a standardized music-related performance task (scale playing with separate hands, seeExperiment 2). In Experiment 1 we tested the hypothesis that a negative influence of non-righthandedness on the instrumental performance in standard playing position would be reflectedin more frequent negative statements of dNRH musicians on the items (dependent variables) ofgeneral hand problems, bodily discomfort, problems with the playing position, expressive skills,
and general sensorimotor skills.
Scale playing is a fundamental aspect of piano technique in classical music as well as in jazz,rock and pop music. The difficulty of temporal evenness in scale playing is a central aspect inthe training of pianistic fluency in both hands and a well-established measurement of pianistic
expertise (Jabusch, Alpers, Kopiez, Vauth, & Altenmüller, 2009). Therefore, in Experiment 2 wetested the sensorimotor performance of separate hands in the subgroup of right- and lefthanded expert pianists. Against the background of existing studies on the relationship between
handedness and hand performance in musicians (e.g., Jäncke et al., 1997), we would argue infavour of the observations of musical practitioners (e.g., Loso, 2004; Mengler, 2004, 2010)
and predict a superior performance of the left over the right hand in left-handed and the rightover the left hand in right-handed musicians (directional hypothesis). Our decision to include
pianists only in Experiment 2 was motivated mainly by technical reasons. MIDI-based scale
analysis provides a precise, reliable and valid measure of motor performance in pianists in a
relevant and standardized motor task. As far as we know, there is currently no method available
for the objective assessment of motor performance of individual hands in non-keyboard instrumentalists with a resolution, reliability and validity comparable with those of the MIDI-based
piano performance measurement.

Experiment 1
MethodParticipants. A total of 47 professional music performers (students and teachers at the Hanover
University of Music, Drama and Media, Germany, mean age 22.6 years, SD 3.6 years, minimum 17 years, maximum 40 years) participated in the experiment (for details see Table 1).
We conducted retrospective interviews (see Jabusch et al., 2009; Lehmann & Ericsson, 1996) toassess accumulated lifetime practice. Participants reported their practice quantity for each yearof their musical careers. Values were summed up for the total duration of their piano training.
Both handedness groups did not differ in age (t(45) 0.23, p 0.82), age at commencement of
instrumental training (t(45) −0.5, p 0.59) or total accumulated practice time (t(45) 1.2,
p 0.23).

Table 1. Description of sample of participants in Experiment 1
Sex

n

dRH
dNRH

21
26

Female

Male

14
17

7
9

Age

Age at beginningof musical training

Total accumulated
practice time (hrs)22.5 (2.7)
22.7 (4.2)

6.95 (3.3)
6.54 (2.0)

10120.5 (5981.5)
12455.5 (7010.8)

Note. dNRH designated non-right-handers, dRH designated right-handers. Numbers in brackets indicate standard
deviations.

Kopiez et al.

363

Classification of handedness groups. The objective classification of handedness was assessed using
a methodological approach based on speed tapping (see Peters & Durding, 1978) and a statistical classification procedure which has been recently introduced to handedness research (Kopiez
et al., 2010). Participants performed speed tapping on a Morse key for 30 seconds with eachhand. Participants tapped twice with a recovery phase of at least 15 minutes between trials. A
Morse key (model by Junker Ltd., Germany; trigger point 300g), connected to a PC, was used,
and tap intervals were recorded using the Software TAPPING (Tapping, 2008). Tapping was
executed with the index and middle finger in combination while the wrist, the forearm and theother fingers were held in a fixed position on the desk. To avoid a start hand effect (Schulze &Vorberg, 2002), the start hand was allocated randomly. All scores were averaged over two trials. To avoid vibrations on the Morse key (which could result in accelerated tapping speed), we
instructed the participants to break contact with the key after each tap. A lateralization coefficient [LC], which indicates performance differences between left and right hand, was calculated, LC 100 × (L−R) ⁄ (LR), with R being the median of inter-tap intervals for the right handand L for the left hand. A high positive LC value indicated a dominance of the right hand, and apositive value near zero or a negative LC value was an indicator for a more balanced cerebral
asymmetry or non-right-handedness (Bryden, Roy, Rohr, & Egilo, 2007). Annett’s (2002)“right shift theory,” with its basic discrimination between genetic right-handers (RH) andnon-right-handers (NRH), served as the theoretical basis of our study. In a previous study(Kopiez et al., 2010), we were able to determine a classification threshold of LC 1.25 for aparticipant’s allocation to the group of designated RH (LC ! 1.25) and designated NRH (LC 
1.25) by applying binary logistic regression. We use the term “designated” (d) handedness,
resulting in the denomination “dRH” and “dNRH”. Our methodological approach of statisticalclassification tries to approximate the “true” or genetic handedness as closely as possible.
Questionnaire on bodily discomfort, instrumental skills, and somatic-emotional lability. The assessment ofbodily discomfort in instrumental performance was based on two questionnaires: first, we useda researcher-developed questionnaire for bodily discomfort (see Appendix 1) in which we
assessed present and previous diseases, injuries and the subjectively-felt constraints in instrumental playing. Second, we used the 24-item inventory, recently developed by von Georgi(2006), to assess the so-called “negative bodily affectivity” (INKA-h, see Appendix 2) as a trait.
Compared with other inventories for measuring somatic-emotional lability, such as the twodimensional Positive Negative Affect Schedule (PANAS; see Watson, Clark, & Tellegen, 1988),
the advantages of the inventory INKA-h are as follows: first, INKA-h measures discomfort(Beschwerden) on a five-point rating scale; second, INKA-h is a validated, one-dimensional inventory that results in a score for somatic-emotional lability as a trait (with only a weak correlation
to bodily arousal). Additionally, there are statistical norms for INKA scores from a healthy
German sample (N 797). Finally, the problem of a skewed distribution of inventory raw scores(with a higher proportion of participants with minor discomfort) is solved by a double logarithm(ln) of (1) each item score and (2) the total INKA-h score. Thus, scores represent double logarithmic values (dln) which are characterized by normal distribution and can be analyzed withparametric statistical procedures. To control for a potential association between INKA-h scoresand neuroticism traits, we conducted the NEO-Five Factors Inventory (NEO-FFI; Costa & McCrae,
1992; McCrae & John, 1992). The NEO-FFI is a multidimensional personality inventory thatconsists of 12 items (descriptions of behaviours), scored on five-point Likert scales, in each of
five personality domains: (1) extraversion; (2) agreeableness; (3) conscientiousness; (4) neuroticism; and (5) openness to experience. The NEO-FFI has been shown to be reliable, valid, andconsistent. For this study, only the dimension of neuroticism was considered.

yes

no

Bodilydiscomfort
yesnoPlaying position
beneficial
pos.

neg.

no

Influence on expressive
skills
pos.

neg.

no

Influence on general
sensorimotor skills

4 (40.0) 6 (60.0)
8 (57.2) 6 (42.8)
0.68
1
0.41
0.17

String playersdRH (n 10)
dNRH (n 14)
F2
Dfp*
Effect size (w)
8 (80.0) 2 (20.0) 5 (50.0) 5 (50.0)
13 (92.8) 1 (7.2) 11 (78.5) 3 (21.5)
0.88
2.14
1
1
0.35
0.14
0.19
0.30

9 (81.8) 2 (18.2) 3 (27.3) 8 (72.7)
10 (83.4) 2 (16.6) 10 (83.4) 2 (16.6)
0.01
7.34
1
1
0.92
 0.01
 0.020.56
0 (0.0) 1 (10.0)
6 (42.8) 1 (7.2)
5.74
2
0.06
0.49

3 (27.3) 2 (18.2)
5 (41.7) 1 (8.3)
0.79
2
0.67
0.19

9 (90.0)
7 (50.0)

6 (54.5)
6 (50.0)

1 (10.0) 1 (10.0)
6 (42.8) 1 (7.2)
3.05
2
0.22
0.36

4 (36.3) 3 (27.3)
5 (41.7) 2 (16.6)
0.38
2
0.83
0.13

8 (80.0)
7 (50.0)

4 (36.3)
5 (41.7)

Note. * all p values two-tailed; ** effect sizes in this section have been calculated based on the equation w = x 2 . Small effect size 0.1, medium effect size 0.3,
Nlarge effect size 0.5. For the theory of effect sizes see Cohen (1988).

6 (54.5) 5 (45.5)
7 (58.3) 5 (41.7)
0.03
1
0.85
0.04

10 (47.6) 11 (52.4) 17 (80.9) 4 (19.1) 13 (61.9) 8 (38.1) 3 (14.3) 3 (14.3) 15 (71.4) 5 (23.8) 4 (19.0) 12 (57.2)
15 (57.7) 11 (42.3) 23 (88.5) 3 (11.6) 21 (80.8) 5 (19.2) 11 (42.3) 2 (7.7) 13 (50.0) 11 (42.3) 3 (11.5) 12 (46.2)
0.47
0.52
2.06
4.43
1.89
1
1
1
2
2
0.49
0.47
0.15
0.11
0.39
0.10
0.10
0.21
0.30
0.20

no

PianistsdRH (n 11)
dNRH (n 12)F2dfp*
Effect size (w)All musiciansdRH (n 21)
dNRH (n 26)
F2
Dfp*
Effect size (w)

yes

Hand
problems

Table 2. The relationship between handedness and different self-reported aspects of instrumental performance in all designated non-right-handed(dNRH) and right-handed (dRH) instrumentalists of Experiment 1.Values indicate frequencies of answers and proportion in percent (in brackets)

364
Psychology of Music 40(3)Kopiez et al.

365

Procedure. Retrospective interviews and tapping tests were conducted in a controlled lab. situation. The entire lab. procedure lasted about 60 minutes. After the classification of handedness,participants received questionnaires on discomfort and sensorimotor problems by mail. The
filling in of the questionnaire took about 30 minutes. Subjects were blinded to the aim of thestudy, and no reimbursement was paid. All participants gave written informed consent.
Institutional ethic committee approval was not required.

Results
The main results can be summarized as follows: a negative relationship between non-righthandedness and the rating of instrumental performance could not be observed either for all 47
participants or for the subgroups of pianists and string players (see Table 2). Although 80.8%of the dNRH musicians rated their playing position as beneficial, compared with 61.9% in
dRH, this relationship between handedness and playing position remains non-significant(F2(1) 2.06, p 0.15). The only significant result was observed for the subsample of pianists:
72.7% of the dRH pianists evaluated their playing position as non-beneficial compared with
only 16.6% of the dNRH pianists (F2(1) 7.34, p  0.01, w 0.56). A similar, non-significant
relationship could be observed for the influence of handedness on expressive skills for the wholesample: dNRH musicians indicated a positive influence in 42.3% of all cases, and no influencein 50.0%, while dRH reported a positive influence in 14.3% of all cases and no influence in
71.4% (F2(2) 4.43, p 0.11). For the subsample of string players, a significant association
between non-right-handedness and positive expressive skills was found (F2(1) 5.74, p  0.01,
w 0.49). No other statistical significance for a negative relationship between non-right-handedness and items related to discomfort or performance skills was found. In the subgroup of
string players, an inverse relationship between non-right-handedness and positively rated
expressive skills could be observed, which nearly reached statistical significance (despite a large
effect size of w 0.49): 42.8% of dNRH string players rated this influence as positive and 50%
reported no influence (F2(2) 5.74, p 0.06) whereas none of the dRH string players reported
a positive influence and 90% reported no influence.
Removal of participants with medical symptoms from the analysis. In the next step of data analysis,
all participants with previous medical symptoms (e.g., tenosynovitis, back pain, scoliosis, or
herniated disk) were removed from the data set, so as not to confound subjectively experienced
bodily discomfort with medical symptoms of the musculoskeletal system. This decision affected
six participants (two dNRH, four dRH). As Table 3 shows, no general statistical significance wasreached in the relationship between non-right-handedness, discomfort, and performancerelated skills. Due to the non-significant influence of previous medical symptoms on the relationship between handedness and the experience of discomfort at the instrument, we decided
to include the aforementioned six participants in the sample for further analyses. Additionally,
the non-reduced sample kept test power constant.
Handedness groups and somatic-emotional lability. To test for differences in the experience ofgeneral somatic-emotional lability, INKA-h scores were compared between handedness
groups. As shown in Figure 1, there were no significant differences in mean somatic-emotional
lability scores between dNRH and dRH (M dNRH 2.34, SD 0.43, M dRH 2.47, SD 0.36;t(45) −1.13, p 0.26 [two-tailed]). However, compared with a reference sample of healthy

no

yes

no

Bodily discomfort
yesnoPlaying position
beneficial
pos.

neg.

no

Influence on expressive
skills

pos.

neg.

no

Influence on general
sensorimotor skills

Note. * all p values two-tailed.

All musiciansdRH (n 17)
8 (47.0) 9 (53.0) 14 (82.3) 3 (17.7) 11 (64.7) 6 (35.3) 3 (17.7) 2 (11.8) 12 (70.5) 5 (29.3) 3 (17.7) 9 (53.0)
dNRH (n 24) 14 (58.3) 10 (41.7) 21 (87.5) 3 (12.5) 20 (83.3) 4 (16.7) 10 (41.7) 2 (8.3) 12 (50.0) 10 (41.7) 3 (12.5) 11 (45.8)
0.50
0.21
1.87
2.65
0.69
F2
df
1
1
1
2
2
p*
0.48
0.65
0.17
0.27
0.71
Effect size (w)
0.11
0.07
0.21
0.25
0.13

Yes

Hand problems

Table 3. The relationship between handedness and different, self-reported aspects of instrumental performance for all designated non-right-handed(dNRH) and right-handed (dRH) instrumentalists in Experiment 1. Compared with Table 2, participants with previous disorders of the musculoskeletal
system have been removed from data set.Values indicate frequencies of answers and proportion in percent (in brackets)

366
Psychology of Music 40(3)Kopiez et al.

367

Figure 1. Ratings (error bars) of general discomfort (Inventory for Negative Bodily Affectivity, INKA-h) by
two groups of handedness (designated right- and non-right-handers). Dashed line indicates average score
for somatic-emotional lability of a healthy reference sample (N = 797).

subjects (N 797), both handedness groups showed a significantly higher INKA-h score(dNRH: t(25) 7.03, p  0.001 [two-tailed], effect size d 1.32, dRH: t(20) 9.22, p  0.001[two-tailed], d 1.94).

Discussion
When looking at the whole sample together, in Experiment 1 none of the results were consistent with our hypothesis of a negative relationship between non-right-handedness and the performance in normal playing position regarding sensorimotor skills as well as the subjectively
feeling of well-being at the instrument. If (statistically non-significant) associations between
handedness and discomfort were to be discussed at all, tendencies would be observed in the
opposite direction: dNRH musicians rated their playing position as more beneficial and lessnegative than did dRH musicians. The control for previous disorders (with medical symptoms)of the musculoskeletal system did not change this observation. In the subsample of pianists(Table 2), this positive association between dNRH and beneficial playing position becomes
highly significant. The same positive relationship exists for the subsample of string players: thenon-right-handed instrumentalist experienced a positive association with their expressive
skills.

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Psychology of Music 40(3)Does this mean that we can rule out a disadvantage of non-right-handedness on instrumental performance on a subjective level of evaluation? Against the background of current effectsizes, the answer is likely to be “yes”. However, we have to bear in mind that all statistical relationships between handedness and subjectively perceived instrumental performance in Table 2
and Table 3 did not exceed an effect size of w 0.49, with most effects being located between
0.10 and 0.30, corresponding to small and medium effects (Cohen, 1988; Rosnow & Rosenthal,2009). For example, the question of hand problems in dNRH only achieved an effect of w 0.10.
Nearly the same indicators of magnitude of effects can be observed for the question of felt
bodily discomfort in dNRH: Although 23 out of 47 musicians reported a subjectively-felt bodily
discomfort in their actual playing position, this did not reach statistical significance and only
indicates a small overall tendency.
Finally, handedness groups did not differ for general (habitual) somatic-emotional lability as
measured by INKA-h. In fact, instrumentalists were characterized by a higher score of somaticemotional lability, compared to the normal healthy population. Somatic-emotional lability
seems to be related to other personality traits such as general emotional lability (e.g., neuroticism). For example, the correlation between INKA scores and N (neuroticism) scores of theNEO-FFI inventory (Costa & McCrae, 1992) in the general population is r 0.44 (for moredetails see von Georgi, 2006, p. 285). In our sample of musicians, we could also observe a correlation between INKA-h and N scores from the NEO-FFI (r(47) 0.35, p  0.01 [one-tailed]). Thisfinding is in keeping with previous observations by Kemp (1996) who concludes that “full-timemusic students display the highest levels of anxiety” (p. 93). Based on the close relationshipbetween the INKA-h scores and tendencies toward neuroticism as well as Kemp’s (1996) statement that “Cattell’s anxiety is more or less equivalent to Eysenck’s neuroticism” (p. 90), we mightreason that instrumentalists in both handedness groups behaved “as usual” in their tendency
towards an increased somatic-emotional lability. However, it remains questionable whether the
result of non-significant differences between right- and non-right-handed professional instrumentalists is limited to this subjective approach (on the level of experienced discomfort and felt
constraints), or if it may also be verified by an objective approach (for example, by the measurement of sensorimotor performance skills). This question will be addressed in Experiment 2.

Experiment 2
MethodParticipants. A total of 19 professional pianists (students at the Hanover University of Music,
Drama and Media, Germany, mean age 23.1 years, SD 2.4 years, minimum 20 years,
Table 4. Description of sample of participants in Experiment 2
n

RH
LH

10
9

Sex
Female

Male

6
3

4
6

Age

Age at beginningof musical training

Total accumulated
practice time (hrs)23.3 (2.5)
22.8 (2.6)

5.6 (2.3)
7.4 (2.3)

18036.1 (8579.8)
15489.1 (14382.5)

Note. RH right handers (preference handedness according to the Edinburgh handedness inventory [LQ ! 33]),
LH left handers (preference handedness according to the Edinburgh handedness inventory [LQ  -33]). Numbers inbrackets indicate standard deviations.

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369

maximum 28 years) participated in the experiment (for details on the musical biography ofparticipants see Table 4). No participant from Experiment 1 took part in Experiment 2. We conducted retrospective interviews (see Jabusch et al., 2009; Lehmann & Ericsson, 1996) to assessparticipants’ accumulated lifetime practice. Participants reported their practice quantity fortime periods of similar practice durations. Values were summed up for the total duration of
their piano training. Both handedness groups did not differ in age (t(17) 0.45, p 0.65), total
accumulated practice time (t(17) 0.47, p 0.64), or age at commencement of instrumental
training (t(17) −1.78, p 0.09 [all t-tests two-tailed]). However, the right-handed group
started slightly earlier with their instrumental training (mean age 5.6 years, SD 2.3) compared with the left-handers (mean age 7.4 years, SD 2.3).
Classification of handedness groups. In Experiment 1 we used an objective method of handedness
classification (speed tapping) combined with a subjective evaluation of well-being at the instrument. In Experiment 2 we used a subjective method of handedness classification (preference
handedness as measured by the well-established Edinburgh handedness inventory; see Oldfield,
1971) combined with an objective method of instrumental performance (scale playing). Our
choice of the Edinburgh handedness inventory (EHI) instead of the speed tapping method forclassification of handedness was mainly motivated by the constrained experimental situation:
any measurement of hand performance differences always causes muscular exhaustion, which
influences the subsequent measures. This effect can only be avoided by a sufficient time (e.g.,
one hour) for recovery. However, due to the limited total experimental time of one hour allowedby the participants (very busy expert pianists), our main interest was in the repeated scale playing performance data and thus no time was left for sufficient recovery. The EHI asks for the
preferred hand used for a number of everyday activities. The laterality quotient is computed as
LQ 100 × (R − L) / (R  L), with the sum of activities performed by the left hand being L andthe sum of activities performed by the right hand being R. This quotient indicates the selfassessed preference handedness of a participant. A positive value indicates the dominance ofthe right hand and vice versa. To accomplish a reliable separation of right-handers (RH) fromleft-handers (LH), the classification threshold for RH was set to LQ ! 33 and for LH to LQ  −33
(entire scale range: −100 to 100). Only those participants with LQ values of ! 33 (for righthanders) and LQ  −33 (for left-handers) were selected for participation in Experiment 2.
For a better understanding of the reliability of this classification method by EHI, it is helpful
to consider the LQ values against the background of the LQ distribution in a large sample. Basedon a large database of LQ values from the EHI (N 1,636, age range 17–40 years), less than
6.5% show a LQ of −33 or smaller and 88.6% show a LQ of 33 and higher (S. Christman,personal communication, 6 August 2010). If we compare these proportions to those of the
distribution of LC values from speed tapping (same age range, N 1,198) from the study by
Kopiez et al. (2010), the proportion of 6.5% (LQ −33 or smaller) corresponds to an LC valueof −3.0 or smaller and the proportion of 88.6% (LQ 33 or higher) to an LC value of 12.9 orhigher. With the cut off value of LC 1.25 for the classification of right- and non-right-handers
in the population of musicians (and of LC 1.89 for the group of nonmusicians, see Kopiez etal., 2010), the choice of an LQ of −33/33 as a classification threshold based on EHI data is far
from the critical LC value of 1.25 and thus avoids handedness misclassification. Assessment ofpreference handedness according to this procedure resulted in a number of nine left-handers(LH) and 10 right-handers (RH) in the sample of Experiment 2 (for details see Table 4).
MIDI based scale analysis. The procedure of scale playing and analysis of temporal unevenness
was performed in accordance with a well-established protocol (Jabusch, Vauth, & Altenmüller,

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Psychology of Music 40(3)2004). Scales were performed on a digital piano (KAWAI MP 9000) which was connected to acomputer. For recording and generating MIDI files, commercially available music editing software was used (Musicator Win, V. 2.12; Music Interactive Technology; Bergen, Norway). Before
the test, participants had the opportunity to warm up for five minutes using their own warm-up
habits and to get used to the keyboard. According to a standardized test protocol (Jabusch et al.,2004), sequences of 10–15 repetitions of C major scales were played over two octaves (range:
C3–C5) in both playing directions (inward and outward), with each hand separately. Participants
were asked to play in legato-style (notes were played in a smooth, connected manner). Fingering
was according to the regular C major fingering (1-2-3-1-2-3-4-1-2-3-1-2-3-4-5 and reverse)
for all participants. Scales were played in 16th notes, and the tempo was standardized at 160
beats per minute for a quarter note, paced by a metronome. Thus, scales were played with
10.66 note onsets per second (93.75 ms per note). Interonset intervals (time between onsets of
two subsequent notes) for all individual notes of the scales were analyzed using the researcherdeveloped software Scale Analysis (Jabusch, 2005) which was originally developed for the quantification of movement disorders in pianists (Jabusch, 2006; Jabusch et al., 2004, 2009;
Jabusch & Altenmüller, 2006). Scale analysis was performed for each hand and in both directions separately. Temporal unevenness of interonset intervals in scale playing was previously
reported to be a precise and reliable indicator of pianists’ motor control (Jabusch et al., 2004).
Medians of the standard deviations of interonset intervals (medSDIOI in milliseconds) of all
performances were calculated for each hand and playing direction.
Procedure. Participants first completed the handedness inventory in a controlled lab. situation
and were then allocated to the respective groups (RH/LH). After performance of the scale-playing task, the retrospective interviews were conducted. The entire procedure lasted about 60
minutes. Participants were blinded to the aim of the study and received no reimbursement. All
participants gave written informed consent. Institutional ethic committee approval was not
required.

Results
Differences between handedness groups. The total descriptive results for all combinations of handedness groups, hands and playing directions are shown in Table 5. Due to the limited numberof subjects, we decided to use non-parametric statistical procedures for data analysis. To evaluate
Table 5. Performance of right-handed (RH) and left-handed (LH) pianists in a standardized performancetask (scale playing). Degree of evenness is indicated by the median of the standard deviation of interonset
intervals (medSDIOI in milliseconds) based on repeated scale performance (10-15 repetitions, tempo: 16th
notes at 160 bpm. For details regarding the analyses see text. Performance is indicated for separate hands
and playing directions (inward vs. outward)
Playing direction
Handedness GroupRH (n 10)
LH (n 9)Hand

Inward direction

Outward direction

Left hand
Right hand
Left hand
Right hand

12.7
10.1
12.7
11.1

13.2
9.7
15.6
11.7

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371

Figure 2. Boxplot of (statistically non-significant) differences in evenness of scale playing between
handedness groups for both hands and playing directions. Higher scores indicate a higher temporal
unevenness.

for differences in unevenness of scale playing between groups (medSDIOI in milliseconds), a
Mann-Whitney U test was conducted for right-handers (RH) and left-handers (LH). The results
for separate groups (Figure 2) did not show a significant difference between groups (z −1.38,
p 0.16 [two-tailed]; average rank in RH: 8.30, average rank in LH: 11.89).
Differences between handedness groups, playing direction and hands. In a next step we analyzed differences between playing directions (inward vs. outward) in handedness groups. The reason for the
analysis of different playing directions is the difference in hand and finger movements for eachdirection: scale playing in the outward (ulnar) playing direction requires so-called thumb-under
movements (3-1 and 4-1 fingering), whereas scale playing in the inward (radial) playing direction requires finger cross-over manoeuvres (1-3 and 1-4 fingering). As previously described by
Jabusch (2006), fundamental differences exist between the movement patterns of both playing
directions, especially in the preparation phases of thumb-under movements and finger crossover manoeuvres.
In the last step of data analysis, we analyzed differences in evenness for the interaction
between the variables handedness group, playing direction and hand. Box plots of results areshown in Figure 3. To test our directional hypothesis of a general superiority in evenness of theleft hand in LH and the right hand in RH, statistical group comparisons were conducted. For
the evaluation of differences, Wilcoxon two-related samples tests were conducted. Fourstatistically-significant differences between hands were found: for RH in the inward playing

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Psychology of Music 40(3)Figure 3. Boxplots of differences in evenness in scale playing between handedness groups, playing
directions and hands in pianists. Degree of evenness is indicated by the median of the standard deviationof interonset intervals (medSDIOI in milliseconds). All differences between hands became statisticallysignificant (Wilcoxon signed ranks test, upper left panel: p = 0.05, upper right panel: p = < 0.01, lower left
panel: p = 0.03, lower right panel: p = 0.02 [all tests one-tailed]).

Table 6. Correlations between variables of musical expertise and scale performance: Results are indicatedfor the total sample of participants (right-handers and left-handers)
medSDIOI (ms)Left hand inward
Left hand outward
Right hand inward
Right hand outward

Age at beginningof piano playing

Number of years
at the piano

Accumulated
practice time (hrs)Actual practicetime (hrs)

0.32
0.53*
0.37
0.28

−0.39
−0.33
−0.46
−0.43

−0.47*−0.23−0.46*−0.50*−0.48*−0.19−0.62**−0.59**

Note. Spearman’s rho: * p  0.05; ** p  0.01 (two-tailed).

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Kopiez et al.

Table 7. Correlations between indicators of expertise and asymmetry between evenness of hands in scaleplaying in right- and left-handers (L minus R value > 0: better right hand performance, L minus R value < 0:better left hand performance)
medSDIOI (ms)L minus R (outward)

Number of years
at the piano

Accumulated
practice time (hrs)Actual practicetime (hrs)Right-handers(n 10)
Left-handers (n 9)

−0.10

0.06

0.20

0.60

0.68*

0.56

Note. Spearman’s rho: * p  0.05 (two-tailed).

direction (upper left panel; z −2.39, p 0.05, effect size d 0.92)1, for RH in the outward playing direction (upper right panel; z −2.80, p  0.01, d 1.27), for LH in the inward playing
direction (lower left panel; z −1.95, p 0.05, d 0.78), and for LH in the outward playing
direction (lower right panel; z −2.07, p 0.02, d 0.87 [all tests one-tailed; due to the robust
non-parametric statistical procedure, repeated analyses with removed outliers from Figure 3
did not show different results]). We would like to point out that all effects are contrary to thedirectional hypothesis and that the right hand performance was always characterized by a better performance (higher degree of evenness).
Relationships between indicators of instrumental expertise and scale performance. In the last step ofdata analysis we looked at relationships between the degree of unevenness in scale playing andindicators of musical expertise as obtained from the musical biography questionnaire. We conducted correlational analyses between the performance data (medSDIOI) for the left and righthands in the inward and outward playing directions and the four biographical variables: (1) age
at commencement of piano training; (2) number of years at the piano; (3) total accumulated
practice time; and (4) actual practice time. As indicated by Table 6, significant results were
found for each of the four selected indicators of expertise. Two indicators correlated significantly with the right-hand performance in outward playing direction: accumulated practicetime (Spearman’s rho −0.50, p  0.05, d −1.15)2 and actual practice time (Spearman’s rho−0.59, p  0.01, d −1.46). In other words, little accumulated practice time, and little actual
practice time were associated with a high degree of unevenness in scale playing for the righthand in the outward direction. Concerning the right hand inward direction, the actual practicetime correlates most with a low degree of unevennes in scale playing (Spearman’s rho −0.62,
p  0.01, d −1.58), followed by the accumulated practice time (Spearman’s rho −0.46,
p  0.05, d −1.03) and number of years at the piano (Spearman’s rho −0.46, p  0.05,
d −1.03). For the left hand outward playing direction, we observed a significant correlation
only between the age at commencement of piano playing and degree of unevenness (Spearman’s
rho 0.53, p  0.05, d 1.25). For the left hand inward direction, significant correlations were
found for the accumulated practice time (Spearman’s rho −0.47, p  0.05, d −1.06) and theactual practice time (Spearman’s rho −0.48, p  0.05, d 1.09 [all tests two-tailed]).
Is the asymmetry between hand performance and the performance advantage of the righthand observed in left- and right-handers (Figure 3) influenced by the practice quantity? To
answer this question, we conducted a correlational analysis between (1) the degree of asymmetry between hand performance (medSDIOI left minus right hand, with a positive value indicating the superiority of the right hand) for both handedness groups and (2) the indicators of374

Psychology of Music 40(3)instrumental expertise (number of years at the piano, accumulated practice time, and actual
practice time; see Table 7). Results indicated one statistically-significant relationship in lefthanders between hand performance asymmetry (in favour of the right hand) and total
accumulated practice time as an indicator of instrumental expertise (Spearman’s rho 0.68,
p  0.05, d 1.85).

Discussion
The main finding of Experiment 2 was that there was no evidence for a sensorimotor disadvantage of left-handedness in expert pianists performing a standardized music-related motor task.
Overall, no differences in the evenness of scale playing were found between handedness groups(see Figure 2). Rather, there was a general tendency of the right hand to play with a higher
degree of evenness compared with the left hand (see Figure 3). This asymmetry in favour of theright hand was seen in right-handers and left-handers. We assume that this asymmetry bias infavour of the right hand is influenced by the long-lasting intensive practice at the piano. Support
for this assumption was given by correlational analyses between indicators of musical expertiseand hand asymmetry scores: the best indicator of expertise, the total accumulated practicetime, was significantly correlated with the right-hand performance superiority in left-handers
in the (difficult to play) outward playing direction (see Table 7). This finding is in line with

Figure 4. Correlation between left minus right hand performance asymmetry (scales in outward playing
direction) in 19 pianists and total accumulated practice time (Spearman’s rho = 0.43, p = 0.03 [one-tailed]).
Scatterplot indicates an increased evenness of right hand performance with increasing accumulated
practice time.

Kopiez et al.

375

previous studies on the role of accumulated practice time for the acquisition of outstanding
musical skills (e.g., Ericsson, Krampe, & Tesch-Römer, 1993; Lehmann, 1997). We found no
significant correlations between indicators of expertise and asymmetry in scale performance
between hands for right-handers. The significant correlation between total accumulated practice time and the asymmetry in scale performance for the entire sample is shown in the scatterplot of Figure 4 (Spearman’s rho 0.43, p 0.03 [one-tailed], d 0.95). This correlationstrongly suggests that the right-hand performance superiority observed in left-handers was aconsequence of a practice-induced improvement of the right hand. However, due to the limited
number of participants in each handedness group, we should bear in mind that this correlation
remains sensitive to outliers. For example, the removal of the upper right participant (Figure 4)
from the sample changes the statistical significance of the correlation, although it still has amedium effect size (Spearman’s rho 0.32, p 0.09, d 0.68).
But how can the superiority of the right hand be explained? A first explanation might bebased on a perceptual focus effect: the melodies in the classical-romantic piano repertoire constitute predominantly the highest voice that is performed with the right hand. Furthermore, themelodies are performed more loudly and sound slightly earlier than the usually softer accompaniment (Goebl, 2001). These performance behaviours render the perceptual salience of melodies considerably higher than those of other parts of the music texture, so that the right handreceives closer attention by the practicing pianist over the years (and thus establishes a finer
timing control) than the left. This explanation is supported by results from previous studies onpitch errors in piano performance which found fewer errors in the melodies (performed by theouter right-hand fingers) than in the non-melody parts (Palmer & van de Sande, 1993).
How can long-term piano practice induce a performance advantage in the right hand ascompared to the left hand? Although the above perceptual explanation is worth considering,
we would like to discuss another explanation for the right hand superiority: the hypothesis ofan overall right-hand bias effect of the piano literature.
Right hand bias in piano literature. Aside from other aspects of technical difficulties in piano playing, a right hand bias in the piano literature should result in a positive difference score of rightminus left hand note counts. To test this assumption, we calculated the note counts (in theprinted score) from three 19th century collections of piano music: Beethoven’s 32 Piano sonatas (notes in the left hand: 122,650; notes in the right hand: 133,064); Chopin’s 24 Preludes
Op. 28 (notes in the left hand: 9,290; notes in the right hand: 9,415); and Chopin’s collectionof 52 Mazurkas (notes in the left hand: 26,308; notes in the right hand: 28,087).
As Figure 5 shows, the difference scores for note counts (right minus left hand) supports ourassumption of a higher number of notes to be performed by the right hand. Although this righthand bias might be considered small (Beethoven Sonatas, median: 4.84%, min.: −35.90, max.:
33.53%; Chopin Preludes, median: 10.05%, min.: −70.66, max.: 58.60; Chopin Mazurkas:
median: 1.03%, min.: 27.00%, max.: 38.45%), we should bear in mind that these small differences in increased right hand training may accumulate over the years of practice and result ina significant sensorimotor training effect that compensates (and even over-compensates) for
the naturally-given hand asymmetry with a left hand dominance in left-handers. As a result of
this bias, left-handed pianists adapt to the demands of the piano repertoire and improve theprecision of their non-dominant right hand to the same superior level (compared with the lefthand) as do right-handed pianists. This assumption of a neurological adaptation effect is supported by the findings of Gaser and Schlaug (2003). The authors investigated structuralchanges in response to long-term motor training in right-handed pianists and found a

376

Psychology of Music 40(3)Figure 5. Boxplots of differences in note counts (right minus left hand) for three collections of pianomusic. Positive medians indicate a higher proportion of notes in the right hand.

correlation between gray matter volume in the left cerebellum and left inferior frontal gyrus,
and the degree of pianistic expertise. This left hemispheric bias in neuroplastic changes is in linewith the right hand bias in note counts of our collection of piano music.

General discussion
In the two studies conducted, we inquired about the potential disadvantage of non-righthandedness on instrumental performance in expert musicians. This hypothetical disadvantage
was based on statements of musical practitioners (e.g., Mengler, 2004) who hypothesized that
non-right-handed string players performing in the standard playing position might experiencedisadvantages in sensorimotor and expressive skills. There are also similar reports on perceived
disadvantages from left-handed pianists (Loso, 2004; Seed, n.d.). However, arguments for anadvantage of non-right-handers in motor learning have also been made (e.g., Judge & Stirling,2003). We employed two complementary approaches in our study: (1) on a subjective level we
asked right- and non-right-handed string and piano players to rate their contentment with
their expressive and technical skills, and to list the frequency of bodily discomfort (Experiment1); (2) on an objective level we measured the performance skills of the dominant and nondominant hands in right- and left-handed pianists with a standardized music-related

Kopiez et al.

377

performance task (Experiment 2). The results of Experiment 1 were not consistent with the
hypothesis of a disadvantage for non-right-handers performing in the non-inverted playing
position – either for pianists or string players. In Experiment 2, the influence of handedness ona standardized and music-related performance task was investigated by scale playing at the
piano. Temporal unevenness of interonset intervals in scale playing has previously been identified as a precise and reliable indicator of pianists’ motor control (Jabusch, 2006; Jabusch et al.,2004). In terms of a directional hypothesis, it was predicted that non-right-handers (or phenotypical left-handers) perform with a higher precision (temporal evenness) when playing scaleswith their dominant left hand and right-handed pianists when playing with their right hand.
However, results gave no support for this prediction: irrespective of handedness, significantly
higher temporal precision was found for the right hands in both groups. Thus, we assume thatprofessional musicians adapt to the standard playing position regardless of their individual
handedness. Handedness-based asymmetry in motor performance is compensated, and evenover-compensated, for by intensive and long-lasting practice on a non-inverted instrument.
This assumption of a long-term adaptation process is supported (1) by the strong influence ofvariables related to expertise acquisition (accumulated practice time, years at the instrumentetc.) on motor control in scale playing and the right hand performance superiority, and (2) by
the right-hand-biased piano literature. One of the best predictors for right-hand superiority forthe scale performance in the difficult outward playing direction was found to be the accumulated and actual practice time (see Tables 6 and 7) – and not the mere years of piano playing.
This finding is in line with past research on the eminent role of deliberate practice in skill acquisition and maintenance (e.g., Ericsson, 1996; Ericsson et al., 1993; Krampe & Ericsson, 1996).
If non-right-handedness is disadvantageous for instrumentalists who want to become professional musicians (but are forced to play in the standard position), we could expect a reduced
incidence of non-right-handers in music students. However, the main result of our previous
study (Kopiez et al., 2010) was that the proportion of designated non-right-handers in bothgroups of instrumentalist (pianists and string players) is significantly higher than the incidenceof about 10–12% of self-declared left-handed musicians as generally reported in other studies.
Surprisingly, among string players we found a proportion of 35% designated non-right-handed
players and among pianists one of 27%. This means that the incidence of (presumptively
genetic) non-right-handers (NRH) in the population of instrumental performers has been significantly underestimated up to now. Our finding is in keeping with the survey study by Laengand Park (1999): the authors found no evidence for a reduced incidence of left-handers in students at a school of music. In the case of an assumed disadvantage effect for NRH performing
an instrument in the standard (right-handed) position, a significantly lower proportion of NRH
would be expected in professional musicians. Finally, professional classical musicians only very
rarely perform their instrument in the inverted playing position as did the pianist reported by
Jäncke et al. (2006). None of our string player subjects did so.
Our results have much relevance for music education. Due to the small body of controlled studies on the influence of handedness on instrumental performance, we propose to be very cautious
about premature recommendations to instrumental beginners to invert the playing position. This
aspect is of particular relevance to string players. Given the strong traditions in the classical musicbusiness, playing in an inverted position might even result in a life-long difficulty for a string player
to get a position in a classical orchestra. Moreover, switching to an inverted playing position would
require a change in the instrument (e.g., restringing of string instruments).
Despite our main conclusion that non-right-handed expert musicians playing in the standard position do not show reduced sensorimotor or other performance-related skills or a limited

378

Psychology of Music 40(3)well-being, we cannot rule out completely that there might be a minority of non-right-handers
who feel uncomfortable or constricted when playing in the standard position. However, currently available methods do not allow us to identify those non-right-handed individuals who
would definitely benefit from an instrumental training in the inverted playing position at the
beginning of their music education.

Limitations and suggestions for future research
The main problem of handedness research is the small number of non-right-handed subjects.
In our study, it took much effort to identify those persons and convince them to participate in astudy. To avoid small cell frequencies in statistical analyses it would be necessary to look for alarge number of non-right-handed musicians, although this might take up more resources
than were available for our study. In Experiment 2 some statistical tendencies would have moreeasily reached significance with a higher number of subjects. In Experiment 2, it would also
have been worthwhile to have additional tasks to the standardized scale playing, such as theperformance of technically-difficult passages. These tasks might have increased the validity ofmeasurement and given additional information about technical proficiency.
Although scale playing is a well-established and validated protocol in movement analysis at
the piano, there is currently no comparable procedure for string instruments. The movement
coordination in string instruments needs a different approach. As Mengler (2010, p. 80ff.)
mentioned, the bowing hand (the so-called “action hand”) initiates the movements of the left
hand. Thus, the bowing (right) hand requires high demands in spatial coordination and force
control which is indispensable for constant sound production. As a consequence, a measurement of sensorimotor performance in string players should consider movement evenness inslow bowing tasks or in fast tone repetitions (see Mengler, 2010, p. 812; von Hasselbach,Gruhn, & Gollhofer, 2010). However, this measurement requires technically-demanding facilities such as motion capture systems.
Our reasoning that the higher demands of piano literature cause adaptive effects in pianists was
based on note counts for the right and left hand. We could imagine that the expert rating of difficulty for right and left hand separately would be more informative than mere note counts. Finally,
all our findings cannot be interpreted in terms of causality. The only way of identifying the processes of sensorimotor adaptation would require a prospective long-term study, starting from the
beginning of instrumental lessons. This approach remains a challenge to handedness research.
Acknowledgements
We are grateful to Richard von Georgi (University of Giessen, Germany), Marco Lehmann (Hanover
University of Music, Drama and Media, Germany) and Werner Goebel (University of Music, Vienna,
Austria) for statistical advice and comments on an earlier version of the manuscript; Craig Sapp (Stanford
University, USA) for providing the statistics of note counts; Stephen Christman (University of Toledo,
USA) for providing the frequency distribution of the Edinburgh Handedness Inventory; and Walter
Mengler (Aachen, Germany) for an inspiring discussion on left-handed string players. We would also liketo thank three anonymous reviewers for helpful comments on an earlier version of this manuscript.

Notes
1.
2.

Post hoc calculation of effect sizes in this section were conducted with the software G*Power V 3.1
1(Faul, Erdfelder, Lang, & Buchner, 2007).
×r
pq
For the calculation of effect size d for correlations we used the equation d = 1 − r with p and q representing the proportion of the sub-samples at the total sample (see Sedlmeier & Renkewitz, 2008,
p. 298).
2

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379

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Biographies
Reinhard Kopiez received a degree in classical guitar, and a Masters and PhD in musicology. He is professorof music psychology at the Hanover University of Music, Drama and Media, Germany and head of the
Hanover Music Lab. From 2000–2003 he was vice-president and since 2009 he is president of ESCOM.
From 2001–2005 he has been president of the German Society for Music Psychology (DGM). His latest
journal publications concern psychological research on music performance, historiometric analyses ofClara Schumann’s repertoire, and music and emotion. Together with A. C. Lehmann and H. Bruhn heedited the German standard handbook on music psychology (Musikpsychologie. Das neue Handbuch, 2008,
Rowohlt).
Hans-Christian Jabusch, MD, holds a piano performance degree and a habilitation degree in systematicmusicology. Following three years of clinical work and scientific research in internal medicine, from 2000
until 2008 he held a postdoctoral position at the Institute of Music Physiology and Musicians’ Medicine,
Hannover, Germany. He is professor of musicians’ medicine and head of the Institute of Musicians’
Medicine at the University of Music Carl Maria von Weber, Dresden, Germany. His scientific interests
include topics in music physiology and performance research such as sensorimotor learning in musiciansand evaluation and optimization of practice strategies. His clinical research is focused on the pathophysiology, diagnostics, treatment and prevention of playing-related disorders in musicians.
Niels Galley received his MD and diploma in psychology in 1968. He was assistant professor for physiology
at the Institute for Psychology, University of Cologne. From 1991–2006 he was professor of biologcial
psychology. His main research areas include lateralization and handedness, the oculomotoric system, andintelligence. Together with Reinhard Kopiez and Andreas C. Lehmann he published a study on the theoretical and methodological foundations of handedness classification (Laterality, 2010).
Jan-Christoph Homann holds a Masters degree in music education and classical piano. As pianist he won different international piano competitions and is an active performer. Since 2009 he has been research assistantfor musicology at the Musicology Seminar at the School of Music Detmold. He is currently completing a postgraduate study in early music as a scholarship holder of the Hanover University of Music, Drama and Media.

382

Psychology of Music 40(3)Andreas C. Lehmann holds a music education degree and a PhD in musicology. From 1992–1998, he wasa postdoctoral fellow in the Department of Psychology at Florida State University. Since 2000 he has been
professor of Systematic Musicology at the Wuerzburg University of Music. He is acting president of theGerman Society for Music Psychology and associate editor of the journal Musicae Scientiae. He recently
published a book entitled Psychology for Musicians (2007, Oxford University Press).
Eckart Altenmüller holds a Masters degree in classical flute, and a MD degree in Neurology and
Neurophysiology. Since 1994 he has been chairman and director of the Institute of Music Physiology andMusicians’ Medicine at the Hanover University of Music, Drama and Media. His main research interests
are motor learning and movement disorders in musicians as well as auditory and sensory learning.
During the last 10 years he received 18 grants from the German Research Society (DFG). Since 2005 hehas been President of the German Society of Music Physiology and Musicians’ Medicine and Member of
the Göttingen Academy of Sciences, Germany.
Appendix 1. Questionnaire for bodily discomfort in musicians
A. General data
Surname, first name _______________________

Subject # ___________

1. Do you have serious health problems or did you have such problems in the past (e.g., injuries or otherdiseases such as hypertension, diabetes, depression)?
Please mark:Diseases:Accidents:
Surgery:

 yes
 no
 yes
 no
 yes
 no

if yes, which and since when?: ___________________
if yes, which and since when?: ___________________
if yes, which and since when?: ___________________

Long-term and regular intake of drugs:
 yes
if yes, which and since when?: ___________________
 no
B. General sensorimotor discomfort
2. Have you ever had sensorimotor problems at the instrument since the beginning of your study? (e.g.,trilling difficulties or velocity problems in one hand).
Please mark: no, never yes, rarely yes, occasionally yes, frequently
 yes, always
If yes, with what kind of playing technique problems was it associated?
______________________________________________________
If yes, which hand was affected?
 right hand left hand both hands

If yes, how do you estimate the severity of problems?
 marginal moderate considerable

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Kopiez et al.

3. If you have ever had pain at the instrument, how would you rate the strongest ever experienced pain
on a scale from 0 to 10? (0 = no pain, 10 = unbearable)
Please mark:
0

1

2

3

4

5

6

7

8

9

 10

4. Do or did you have bodily discomfort in relation to instrumental performance?
 no yes, namely _______________________________________________

If no, please continue with question #6
If yes, please mark in the figure below the affected regions with a cross (X), where you experienced thestrongest discomfort and with a circle (O) any additionally affected regions.

C. Current playing situation
5. How would you rate your current (conventional) playing position with regard to your performanceskills?

384

Psychology of Music 40(3) the conventional playing position is advantageous the conventional playing position is disadvantageous
Why is the current playing position disadvantageous? ___________________________
6. Do you think your handedness has a positive/negative/no influence on your performance skills?
On playing technique and dexterity:
 positive
 negative
 no effectOn expressive skills:
 positive
 negative
 no effectAppendix 2. Inventory for Negative Bodily Affectivity (INKA-h) (von Georgi, 2006).
The table shows a number of items related to bodily discomfort. Please mark which discomfort you tend
to suffer from. Please rate the degree you feel constricted by the respective discomfort.

{ not present
Exhaustibility
Lightheadedness
Palpitations
Feeling of fullness
Pressure-sensations in the head
Stabbing chest pains
Disequilibrium
Hot flushes
Insomnia
NauseaHeadacheHeart trouble
Leg fatigue
Shortness of breath
Aching limbs
Fatigue
Neck pains
Shivers
Back pain
Dizziness
Lump in the throat
Feeling of weakness/languor
Tiredness
Numbness{ marginal{ mild{ vastly{ severe