The
Relationship between Music and Language
Lutz
Jäncke1,*
Traditionally,
music and language have been treated as different psychological faculties. This
duality is reflected in older theories about the lateralization of speech and
music in that speech functions were thought to be localized in the left and
music functions in the right-hemisphere of the brain. For example, the landmark
paper of Bever and Chiarello (1974) emphasized the different roles of
both hemispheres in processing music and language information, with the left
hemisphere considered more specialized for propositional, analytic, and serial
processing and the right-hemisphere more specialized for appositional,
holistic, and synthetic relations.
This view has been challenged in recent
years mainly because of the advent of modern brain imaging techniques and the
improvement in neurophysiological measures to investigate brain functions.
Using these innovative approaches, an entirely new view on the neural and
psychological underpinnings of music and speech has evolved.
The findings of
these more recent studies show that music and speech functions have many
aspects in common and that several neural modules are similarly involved in
speech and music (Tallal and Gaab, 2006). There is also emerging evidence
that speech functions can benefit from music functions and vice versa. This
field of research has accumulated a lot of new information and it is therefore
timely to bring together the work of those researchers who have been most
visible, productive, and inspiring in this field.
This
special issue comprises a collection of 20 review and research papers that
focus on the specific relationship between music and language. Of these 20
papers 12 are research papers that report entirely new findings supporting the
close relationship between music and language functions. Two papers report
findings demonstrating that phonological awareness, which is pivotal for
reading and writing skills, is closely related to pitch awareness and musical
expertise (Dege and Schwarzer, 2011; Loui et al., 2011). Dege and colleagues even show that
pre-schoolers can benefit from a program of musical training to increase their
phonological awareness.
Three
research papers focus on the relationship between tonal language expertise and
musical pitch perception skills and on whether pitch-processing deficits might
influence tonal language perception. Giuliano et al. (2011) demonstrated Mandarin speakers are
highly sensitive to small pitch changes and interval distances, a sensitivity
that was absent in the control group.
Using ERPs obtained during the pitch and
interval perception tasks, their study reveals earlier ERP responses in
Mandarin speakers compared with controls to these pitch changes relative to
no-change trials.
In their elegant paper, Peretz et al. (2011) report that native speakers of a
tone language, in which pitch contributes to word meaning, are impaired in the
discrimination of falling pitches in tone sequences as compared with speakers
of a non-tone language.
Taken together, these two studies illustrate the
cross-domain influence of language experience on the perception of pitch,
suggesting that the native use of tonal pitch contours in language leads to a
general enhancement in the acuity of pitch representations. Tillmann et al. (2011) examined whether subjects suffering
from congenital amusia also demonstrate impairments of pitch-processing in
speech, specifically the pitch changes used to contrast lexical tones in tonal
languages.
Their study revealed that the performance of congenital amusics was
inferior to that of controls for all materials including the Mandarin language,
this therefore suggesting a domain-general pitch-processing deficit.
Five
research papers sought to examine interactions either between musical expertise
and language functions or whether an interaction between musical and language
functions is beneficial for phonetic perception. Ott et al. (2011) demonstrate that professional
musicians process unvoiced stimuli (irrespective of whether these stimuli are
speech or non-speech stimuli) differently than controls, this suggesting that
early phonetic processing is differently organized depending on musical
expertise.
Strait and Kraus (2011) report perceptual advantages in
musicians for hearing and neural encoding of speech in background noise. They
also argue that musicians possess a neural proficiency for selectively engaging
and sustaining auditory attention to language and that music thus represents a
potential benefit for auditory training.
Gordon et al. (2011) examined the interaction between
linguistic stress and musical meter and established that alignment of
linguistic stress and musical meter in song enhances musical beat tracking and
comprehension of lyrics. Their study thus supports the notion of a strong
relationship between linguistic and musical rhythm in songs.
Hoch et al. (2011) investigated the effect of a musical
chord's tonal function on syntactic and semantic processing and conclude that
neural and psychological resources of music and language processing strongly
overlap. The fifth paper of this group (Omigie and Stewart, 2011) demonstrates that the difficulties
amusic individuals have with real-world music cannot be accounted for by an
inability to internalize lower-order statistical regularities but may arise
from other factors. Although there are still some differences between music and
speech-processing, there thus is growing evidence that speech and music
processing strongly overlap.
Halwani
et al. (2011) examined whether the arcuate fasciculus, a prominent white-matter
tract connecting temporal and frontal brain regions, is anatomically different
between singers, instrumentalists, and non-musicians. They showed that
long-term vocal–motor training might lead to an increase in volume and
microstructural complexity (as indexed by fractional anisotropy measures) of
the arcuate fasciculus in singers.
Most likely, these anatomical changes
reflect the necessity in singers of strongly linking together frontal and
temporal brain regions. Typically, these regions are also involved in the
control of many speech functions. The beneficial impact of music on speech
functions has also been demonstrated by Vines et al. (2011) in their research paper.
They
examined whether the melodic intonation therapy (MIT) in Broca's aphasics can
be improved by simultaneously applying anodal transcranial direct current
stimulation (tDCS). In fact, they showed that the combination of
right-hemisphere anodal-tDCS with MIT speeded up recovery from post-stroke aphasia.
In
addition to these 12 research papers there are 8 review and opinion papers that
highlight the tight link between music and language. Patel (2011) proposes the so-called OPERA
hypothesis with which he explains why music is beneficial for many language
functions.
The acronym OPERA stands for five conditions which might drive
plasticity in speech-processing networks (Overlap: anatomical overlap in the
brain networks that process acoustic features used in both music and speech;
Precision: music places higher demands on these shared networks than does
speech; Emotion: the musical activities that engage this network elicit strong
positive emotion; Repetition: the musical activities that engage this network
are frequently repeated; Attention: the musical activities that engage this
network are associated with focused attention).
According to the OPERA
hypothesis, when these conditions are met, neural plasticity drives the
networks in question to function with higher precision than needed for ordinary
speech communication. While Patel's paper is more an opinion paper that puts
musical expertise into a broader context, the seven other reviews more or less
emphasize specific aspects of the current literature on music and language.
Ettlinger et al. (2011) emphasize the specific role of
implicitly acquired knowledge, implicit memory, and their associated neural
structures in the acquisition of linguistic or musical grammar. Milovanov and
Tervaniemi (2011) underscore the beneficial influence
of musical aptitude on the acquisition linguistic skills as for example in
acquiring a second language.
Bella et al. (2011) summarize findings of the existing
literature concerning normal singing and poor-pitch singing and suggest that
pitch imitation may be selectively inaccurate in the music domain without being
affected in speech, thus supporting the separability of mechanisms subserving
pitch production in music and language. In their extensive review of the
literature, Besson et al. (2011) discuss the transfer effects from
music to speech by specifically focusing on the musical expertise in musicians.
Shahin (2011) article reviews neurophysiological
evidence supporting an influence of musical training on speech perception at
the sensory level, and the question is discussed whether such transfer could
facilitate speech perception in individuals with hearing loss. This review also
explains the basic neurophysiological measures used in the neurophysiological
studies of speech and music perception.
The comprehensive review by Koelsch (2011) summarizes findings from
neurophysiology and brain imaging on music and language processing and
integrates these findings into a broader “neurocognitive model of music
perception.” Specific emphasis is placed on the comparison of musical syntax
and their similarities and differences to language syntax.
Schon and Francois (2011) present a review in which they focus
on a series of electrophysiological studies that investigated speech
segmentation and the extraction of linguistic versus musical information. They
demonstrated that musical expertise facilitates the learning of both linguistic
and musical structures. A further point is that electrophysiological measures
are often more sensitive for identifying music-related differences than
behavioral measures.
Taken
together, this special issue provides a comprehensive summary of the current
knowledge on the tight relationship between music and language functions. Thus,
musical training may aid in the prevention, rehabilitation, and remediation of
a wide range of language, listening, and learning impairments. On the other
hand, this body of evidence might shed new light on how the human brain uses
shared network capabilities to generate and control different functions.
