The ability to comprehend and produce language and music is unique to humans (Patel, 2010). Since both domains share structural and auditory complexity, strong parallels between music and language have already been proposed alongside some differences, with an emphasis on possible applications of music to educational settings (Strait & Kraus, 2011). An increasing number of studies have put forward the possible benefits of music training on non-musical learning domains such as verbal intelligence, executive function, creativity, arithmetic processing and linguistic abilities (Gibson, Folley, & Park, 2009; Hoch & Tillman, 2012; Moreno et al., 2009, 2011).

There are firm scientific grounds for a link between musical abilities and first (L1) and/or second language (L2) proficiency. Firstly, musical and speech sounds are segmented and processed similarly by the auditory system (François, Chobert, Besson, & Schön, 2012; Schön et al., 2010). Secondly, these components of language and music may be compounded into larger meaningful units in a structured hierarchical manner—grammar and harmony or rhythm (Patel, 2010; Sloboda, 1985). This shared syntactic integration resource hypothesis (Patel, 2003) challenges the domain-specificity approach and argues that, although representations of music and language components may be stored in different brain regions, a common neural network is used to interpret and structure music and speech sounds (Schön et al., 2010). Therefore, musical practice and expertise fine-tune the auditory system for both music and speech processing and, in turn, strengthen related neural and cognitive mechanisms (Kraus, Strait, & Parbery-Clark, 2012).

In particular, the behavioural and neurological effects of musical expertise on native language proficiency have been extensively researched (Parbery-Clark, Tierney, Strait, & Kraus, 2012). However, less is known about how music training or expertise could impact upon L2 learning. To identify possible benefits of musicianship, Slevc and Miyake (2006) conducted a pioneering study which provided clear evidence for the transfer of musical skills to L2 receptive and productive phonology, as distinct from L2 syntax or lexicon. By concluding that musical expertise may assist only L2 sound structure acquisition, this influential study set the direction for subsequent research, which largely examined the phonological aspects in L2 learning.

With respect to shared syntax and meaning processing in music and language, research suggests that the neurophysiological mechanisms responsible for syntax are enhanced, and develop earlier, due to musical training (Jentschke & Koelsch, 2009; Slevc, Rosenberg, & Patel, 2009). In addition, speech recognition and production depend on, and operate simultaneously with, conceptually-driven processes, such as awareness of the lexical, syntactic and semantic aspects of language (Rapp & Goldrick, 2000). Research suggests that two shared cognitive processes may underlie linguistic and musical syntax: working memory or executive functioning, and implicit learning (i.e., the ability to uncover an abstract structure from noisy input; Moreno et al., 2011; Francois & Schön, 2011). Although there is on-going research on the syntactic links between music and language (Slevc, 2012), no studies to date have been conducted to examine how music through these shared resources may influence the learning of L2 syntax and grammar. Due to the lack of studies regarding L2 structure and meaning aspects, this article discusses the available research on the potential phonological and reading benefits of musical experience on L2 learning.

Previous review articles have concentrated on the effects of musical experience on auditory and speech processing skills (Besson, Chobert, & Marie, 2011; Kraus & Chandrasekaran, 2010; Strait & Kraus, 2011) or on the general link between music and language (Asaridou & McQueen, 2013; Slevc, 2012). One recent review did examine the music – L1 and L2 relationship with an emphasis on brain processes (Chobert & Besson, 2013). However, the present article aims at presenting an overview and critically reflecting on the impact of music education and/or expertise on certain L2 learning skills, by examining:

Method

The article employs a method of research literature analysis to examine the possible benefits of music education and expertise on L2 skills.

Systematic search for peer-reviewed articles was carried out in EBSCOhost (PsycARTICLES, PsycINFO), Scopus and Web of Science databases, using the keywords “music”, in combination with “second language”, “L2”, and/or “foreign language”.

Inclusion criteria were defined as the regency of the article (i.e. not older than 7 years) and also the impact factor (higher than 1.5) of the journals included in ©Thomson Reuters Journal Citation Reports. Initial search in November 2012 combined with a more updated search in January 2014 yielded 56 hits, 13 of which were included in the present article’s analysis. Among these 56 hits, there were a relatively restricted number of articles within the chosen particular topic (i.e., music’s effect on L2), therefore few were excluded in practice. I chose articles that concentrated on the psychological aspects of the music-L2 relationship, thus following an experimental psychology perspective and methodology as well as using quantitative statistical analysis of data. Articles that were of a descriptive nature were excluded. Nonetheless, the chosen papers were selected to represent as many linguistic subdomains and as wide a range of musical activities as possible.

Analysis of Evidence for the music-L2 transfer effects A more detailed overview of the methods and findings of relevant articles can be found in Tables 1, 2, 3, and 4. The arguments will be directed by methods of analysis of relevant articles and rational reflection. The analysis and arguments will be organized thematically as follows. Article Sample:

size, age, musical experience Native language - L2 Measures Findings Delogu et al.

( 2010 N=90

Adults

Controls, musicians, Mandarin Chinese experts

N=20

Children (6–8 years)

High and Low Musical ability groups Italian - Mandarin Chinese Musical ability;

L2 receptive phonology;

Lexical tone discrimination;

Years of musical training. Adult musicians performed better than musically naive subjects and equivalently to Chinese experts in the lexical tone discrimination task



Children with a higher musical ability showed higher tonal performance.



The discrimination of segmental variations (consonant or vowel changes), was not enhanced in musically able subjects. Lee & Hung

( 2008 N=72

Adults

Musicians and non-musicians English – Mandarin Chinese Processing of linguistic and musical pitch Musicians more accurate at identifying correct syllables among intact or modified syllables in pitch height or pitch contour. Marie et al.

( 2011 a N=22

Adults

Musicians and non-musicians French – Mandarin Chinese Lexical tone and segmental processing;

ERPs. Musicians were faster and more accurate at detecting both tonal and segmental variations than non-musicians.



Musical expertise improved the perception and categorization of segmental and tonal linguistic contrasts. Marques et al.

( 2007 N=22

Adults

Musicians and non-musicians French - Portuguese Lexical tone processing;

ERPs. Musicians were faster and more accurate than non-musicians in detecting prosodic pitch violations. Martínez-Montes et al.

( 2013 N=52

Adults

Musicians and non-musicians Spanish – Mandarin Chinese Syllabic pitch processing;

ERPs. Musicians showed larger mismatch negativity MMNs to pitch contour deviations in both harmonic sounds and L2 syllables. Article Sample:

size, age, musical experience Native language - L2 Measures Findings Herrera et al.

( 2011 N=97

Pre-school children, (Mean age 4.5 years)

None Spanish- Spanish and Tamazight-Spanish Intelligence;

Spanish vocabulary;

Phonological awareness;

Naming speed;

Verbal short-term memory (STM). Applied Intervention: 2 eight-week training periods of phonological training with/without music over 2 years. Early phonological and musical intervention improved both naming speed and phonological awareness (two predictors of reading readiness) in native speakers and L2 learners.



L2 learners who received training with music developed naming speed skills and phonological awareness of the ending of words more rapidly than Spanish children in the control group. François et al.

( 2012 N=24

Children (Mean age = 8)

None French – artificial language Verbal Comprehension;

Perceptual Reasoning;

Working Memory and Attention Speech segmentation ERPs Applied intervention: 2 year training in music or painting Children with musical training improved their speech segmentation abilities while children in the painting group did not.



The difference in the electrophysiological responses for familiar and unfamiliar words was greater in the music group than in the painting group. Sadakata & Sekiyama

( 2011 N=53 (Dutch)

N=54 (Japanese)

Adults

Musicians (excluding singers) and non-musicians Japanese-Dutch and Dutch-Japanese L2 receptive phonology - the timing and quality of Japanese consonants, and the quality of Dutch vowels. Musical expertise benefited discrimination of speech materials (indicating automatic neural encoding processes) more than identification (application of categories to an incoming sound) in both L1 and L2.



Musicians showed the greatest enhancement in the identification of temporal aspects of speech (duration of consonants and vowels). Article Sample:

size, age, musical experience Native language - L2 Measures Findings Posedel et al.

( 2011 N=45

Adults

Years of musical training as a continuous variable English-Spanish Working memory (Operation span);

Pitch perception;

L2 phonological production;

Start and duration of music and L2 training. Correlation between the length of musical training and both pitch perception and working memory.



Pitch perception was the only significant predictor of Spanish pronunciation quality. Milovanov et al.

( 2008 N=40

Children (10–12 years).

Musically trained or untrained Finnish-English Musical aptitude

Pronunciation

ERPs Children with advanced English pronunciation abilities had better musical skills than those who showed less accurate English pronunciation skills.



Children with good linguistic skills showed more pronounced sound-change evoked activation with the music stimuli. Milovanov et al.

( 2010 N=46

Adults

Non-musicians, choir members, English philology students Finnish-English Musical aptitude;

Pronunciation;

Phonemic listening discrimination. All the participants performed equally well in the phonemic listening discrimination task.



The participants with higher musical aptitude were able to pronounce English better than the participants with less musical aptitude. Article Sample:

size, age, musical experience Native language - L2 Measures Findings Strait et al.

( 2011 N=42

Children (Mean age = 10.4)

None English Oral and silent reading;

Musical aptitude;

Attention/Auditory Working Memory (AWM);

Human auditory brainstem responses The music aptitude, by means of shared neural (brainstem) and cognitive (AWM/Attention) mechanisms, accounted for 38% of variance in children’s reading abilities.



The effect of musical aptitude largely came from children’s rhythmic skills. Swaminathan & Gopinath

( 2013 N=76

Primary school children

Musically trained and untrained Indian languages - English Verbal intelligence,

Wechsler’s Intelligence Scale for Children (WISC);

English reading proficiency Children with music training (Western or Indian) perform better than untrained children in L2 comprehension and vocabulary, but not in reading proficiency.

Enhanced Phonological Processing and Production and L2 Comprehension In order to define the possible benefits of musical ability on L2 learning, it is necessary to explain how diverse linguistic subdomains can be affected by this cross-domain relationship. As auditory qualities of language and music are more tangible than semantic ones, a considerable amount of research has been done on the effect of musical training on pitch and duration perception in speech. Enhanced processing of tonal variations. Firstly, it has been found that musically able adults detect and identify foreign language lexical tone variation better than adults without musical background. Analysis of research literature indicates that tonal fluctuation processing has been studied most extensively (see Table 1). For example, Marques, Moreno, Castro, and Besson (2007) demonstrated that musicians more easily detect diminutive prosodic pitch deviations; whereas, Delogu, Lampis, and Belardinelli (2010) indicated that both musically able children and adults are better at discriminating lexical tones, but not phoneme duration variation. Lee and Hung (2008) extended findings regarding enhanced discrimination abilities and showed that musicians are also more accurate at identifying pitch height and pitch contour in speech. At the neurophysiological level, this music experience advantage persists – studies using event-related potentials (ERPs) reveal that musicians categorize tonal changes more easily and confidently (Marie, Delogu, Lampis, Belardinelli, & Besson, 2011). Musicians are also faster to categorize prosodic variation (Marques et al., 2007), and more sensitive to foreign syllabic tone change (Martínez-Montes et al., 2013). Enhanced processing of utterance duration. Secondly, musical experience has a beneficial impact on the processing of phoneme duration and overall language segmentation (see Table 2). Marie et al. (2011), in contrast to Delogu et al. (2010), showed that musical training enhanced discrimination and categorization of both segmental and tonal contrasts. In a cross-linguistic study, Sadakata and Sekiyama (2011) compared musicians and non-musicians and found that musical expertise benefited discrimination of speech materials more than identification in both L1 and L2, and the greatest effect of musicality on identification processes was seen in the temporal aspects of speech (duration of consonants and vowels). Therefore, musicianship enhanced automatic neural encoding to a greater extent than the application of categories to an incoming sound. Importantly, the enhancement effect interacted with the previous experience of the linguistic background—for example; Dutch musicians did not outperform Japanese musicians and non-musicians on sensitivity to certain specific Japanese language material. The distinctiveness of perceptual cues depended on the type of first language—implying that some languages themselves enhance phonological perception more than other languages. Moreover, François, et al. (2012) experimentally assigned children to 2 years of music and painting training and noted that only musical training improved speech segmentation abilities in an artificial language as demonstrated by behavioural and electrophysiological responses. Herrera, Lorenzo, Defior, Fernandez-Smith, and Costa-Giomi (2011) used a similar paradigm and showed that a 2-year phonological and musical intervention improved both naming and phonological awareness of real language words. Therefore, research suggests that music training may enhance phonological perception (tonal and timing) at both early processing and categorical perception levels. Enhanced pronunciation. Thirdly, musical training has a positive impact on L2 phonological production abilities (see Table 3), and this is most likely mediated by the effects of musical training length on pitch perception ability as suggested by Posedel, Emery, Souza, and Fountain (2011). In their study, pitch perception was the only significant predictor of Spanish pronunciation quality. Perhaps due to the smaller sample, the length of musical education was not significantly correlated with pitch perception, L2 pronunciation or working memory (WM) within the group of musically trained individuals. Milovanov, Huotilainenc, Välimäkid, Esquef, and Tervaniemi (2008) studied children and demonstrated the opposite direction of the relationship between music ability and L2 skills – Finnish children with advanced English pronunciation abilities had higher musical aptitude. Such findings were supported using adult participants; however, musical aptitude had no additional advantage on phonemic discrimination (Milovanov, Pietilä, Tervaniemi, & Esquef, 2010). Enhanced L2 comprehension. Fourthly, the perception of a written text, that is, reading, can also be enhanced by musical training, although there have been fewer research articles published on this topic (see Table 4). Herrera et al. (2011) demonstrated that 2 years of phonological and music training improve reading readiness in native speakers and L2 learners. Strait, Hornickel, and Kraus (2011) examined older children and showed that musical aptitude (and particularly rhythmic abilities) is related to reading skills. Furthermore, Swaminathan and Gopinath (2013) studied primary-school children speaking various Indian languages, and found that those who were trained in Western or Indian music performed better in English L2 comprehension and vocabulary, and this advantage was not due to familiarity with English music tradition. Thematic overview. When comparing the above four sub-themes, a certain number of observations can be made. To start with, Sadakata and Sekiyama’s (2011) results are in line with Marie et al.’s (2011) findings from event-related potentials, which measured responses to the tonal processing of the Mandarin language. Although Japanese has simpler tone systems, both studies found enhanced perceptual processing and categorization of important L2 contrasts. The choice to study two very different languages (Dutch and Japanese) was an advance, because intonation, spectral and timing features are prominent in music and in these languages. The Strait et al. (2011) findings can potentially explain how identification of L2 categories occurs in Sadakata and Sekiyama’s (2011) study. Although identification (application of categorical information to auditory stimulus) is a perceptually and cognitively challenging task, and the learning of L2 sound categories was very short, musicians might have been faster than non-musicians to acquire foreign categories as an acoustic regularity. Since word meaning in the Japanese and Dutch languages changes with the temporal and spectral qualities of sound, respectively, these languages require joining together the temporal/spectral and syllabic material. Delogu et al. (2010) and Marie et al. (2011) also suggest that the positive effect of music expertise on enhanced perceptual processing might arise because musicians rely on both left-lateralized segmental cue processing and right-lateralized tonal cue processing. Therefore, weaker brain lateralization and enhanced subcortical processing, induced by musical activities, could play a role in learning L2 that is very different from the native one. Next, the Posedel et al. (2011) finding that the length of musical training within the musicians group was not correlated with pitch perception or Spanish productive phonology skills contradicts most previous findings as well as Sadakata and Sekiyama’s (2011) results, as in their study the duration of training positively affected the accuracy of identification performance. This discrepancy could be explained by differing participants in the two studies—Posedel et al. (2011) only accounted for the length of musical training, whereas Sadakata and Sekiyama (2011) defined their musician sample as experts with current active involvement in musical activities. Posedel et al.’s (2011) finding in which only the pitch perception, but not the years of music training, influenced pronunciation is consistent with the Milovanov et al.’s (2008, 2010) findings that children and adults with advanced English pronunciation abilities have higher musical aptitude. Thus, it is not surprising that the years of training per se might not directly translate to better musical and phonological skills, but pitch perception abilities, which are a solid quality of musical aptitude, may have a more direct effect on L2 productive phonology. The phonological awareness of L2 seems to be positively affected not only by musical expertise, but also by training (e.g., Herrera et al., 2011) and innate predisposition to musical expertise (e.g., Strait et al., 2011). Pre-school children who received musical training had enhanced phonological awareness in a distinctly different language from their mother-tongue (Tamazight), similarly to adult musicians in Sadakata and Sekiyama’s (2011) study. Strait et al. (2011) not only eliminated the effects of musical training, but showed that even musical aptitude could predict speech processing abilities by the enhanced perception of rhythmic regularities, which adds to Sadakata and Sekiyama’s (2011) emphasis on spectral and temporal aspects.

Conceptualisation of Terms—What Is Musical Training or Expertise? The relationship between musical training and expertise. Only 2 studies from the selected articles asked participants to go into music training, whilst the majority of others assumed that the quality of music training was sufficient to result in musical expertise that would initiate L2 skills enhancement. Herrera et al. (2011) carried out a 2-year follow-up study on pre-school children. Participants received either phonological training with music (based on children’s rhymes and songs) or without music. The phonological training greatly improved both naming speed and phonological awareness, which are two strong predictors of reading readiness. Tamazight children, who received training with music, developed their L2 (i.e., Spanish) naming speed skills and phonological awareness of word endings more rapidly than Spanish children in the control group. François et al. (2012) also carried out 2 years of music training and showed that the speech segmentation abilities of an artificial L2 were improved in children who underwent music compared to art training. These studies thus provide evidence for music training nurturing brain plasticity and facilitating L2 phonological and verbal comprehension skills whilst controlling for potential antecedent inclination towards music as a cause for these changes. Musical expertise and its possible confounds. It follows that when broad and complex issues like music or language are being investigated, the terminology and validity of measures that studies use are of critical importance. Herrera et al. (2011), Sadakata and Sekiyama (2011), and Strait et al. (2011) tested for pre-existing differences between the groups, such as general cognitive abilities and relevant confounding factors. However, Posedel et al. (2011) treated participants as a homogenous sample and did not account for intelligence and L2 vocabulary knowledge, as Herrera et al.’s (2011) study did. Furthermore, Posedel et al. (2011) tested the amount of formal Spanish training as a single measure of pre-existing L2 competency, despite the fact that informal exposure to Spanish culture or the overall individual differences in Spanish proficiency, gained after a particular amount of formal training, could affect the phonological production. The Posedel et al. (2011) study could have benefited from inspecting the subjective self-ratings of L2 expertise (as was done in Sadakata & Sekiyama’s, 2011 study), since it is known that the length of exposure to L2 improves the phonological abilities (Slevc & Miyake, 2006). Swaminathan and Gopinath (2013), on the other hand, provide evidence for the music-L2 link using participants with non-Western music training, which not only extends the transfer effects from Western Classical music training but also aims to control for exposure to the L2 culture. Vocal versus instrumental musical expertise. It is also important to note that the majority of studies examined the effects of instrumental expertise, explicitly excluding singing as a type of musical training without explaining the reasons behind it. Yet, the Herrera et al. (2011) study was based on spoken and singing training that engaged children in various activities, but did not teach music per se and still attained remarkable L2 improvements. Similarly, Ludke, Ferreira and Overy (2013) found that the “listen-and-sing” learning method can facilitate verbatim memory for L2 phrases after a brief 15-min learning period, but musical ability and training do not facilitate this effect. In contrast, Moreno et al. (2009) and François et al. (2012) used formal musical training which consisted of several well-established methodologies (i.e., Kodaly and Orff) and found very similar effects to findings in Herrera et al.’s (2011) study—improved reading skill, pitch discrimination and speech segmentation. Whereas the aforementioned music education methodologies include the active use of one’s voice, Schön et al. (2008) showed that mere listening to a vocalization rather than a speech fragment evoked strong language learning facilitation. However, it is understandable that some researchers eliminate musical expertise gained from singing, since singers usually know how to play at least one instrument, and this is practiced in formal musical education and is naturally relevant. The observation that singing may involve instrumental expertise implies that singing might provide additional L2 enhancement; therefore, it may be hard to disentangle the effects of each. Indeed, very diverse definitions of musical experience and methods have been used, but similar positive results for music-L2 transfer were achieved in the aforementioned research.