Evidence for shared cognitive processing of pitch in music and language

The human language system, including its inferior frontal component in "Broca's area," does not support music perception

Language and music are two human-unique capacities whose relationship remains debated. Some have argued for overlap in processing mechanisms, especially for structure processing. Such claims often concern the inferior frontal component of the language system located within "Broca's area." However, others have failed to find overlap. Using a robust individual-subject fMRI approach, we examined the responses of language brain regions to music stimuli, and probed the musical abilities of individuals with severe aphasia. Across 4 experiments, we obtained a clear answer: music perception does not engage the language system, and judgments about music structure are possible even in the presence of severe damage to the language network. In particular, the language regions' responses to music are generally low, often below the fixation baseline, and never exceed responses elicited by nonmusic auditory conditions, like animal sounds. Furthermore, the language regions are not sensitive to music structure: they show low responses to both intact and structure-scrambled music, and to melodies with vs. without structural violations. Finally, in line with past patient investigations, individuals with aphasia, who cannot judge sentence grammaticality, perform well on melody well-formedness judgments. Thus, the mechanisms that process structure in language do not appear to process music, including music syntax.

The Musical Abilities, Pleiotropy, Language, and Environment (MAPLE) Framework for Understanding Musicality-Language Links Across the Lifespan

Using individual differences approaches, a growing body of literature finds positive associations between musicality and language-related abilities, complementing prior findings of links between musical training and language skills. Despite these associations, musicality has been often overlooked in mainstream models of individual differences in language acquisition and development. To better understand the biological basis of these individual differences, we propose the Musical Abilities, Pleiotropy, Language, and Environment (MAPLE) framework. This novel integrative framework posits that musical and language-related abilities likely share some common genetic architecture (i.e., genetic pleiotropy) in addition to some degree of overlapping neural endophenotypes, and genetic influences on musically and linguistically enriched environments. Drawing upon recent advances in genomic methodologies for unraveling pleiotropy, we outline testable predictions for future research on language development and how its underlying neurobiological substrates may be supported by genetic pleiotropy with musicality. In support of the MAPLE framework, we review and discuss findings from over seventy behavioral and neural studies, highlighting that musicality is robustly associated with individual differences in a range of speech-language skills required for communication and development. These include speech perception-in-noise, prosodic perception, morphosyntactic skills, phonological skills, reading skills, and aspects of second/foreign language learning. Overall, the current work provides a clear agenda and framework for studying musicality-language links using individual differences approaches, with an emphasis on leveraging advances in the genomics of complex musicality and language traits.

Categorical Perception of Mandarin Pitch Directions by Cantonese-Speaking Musicians and Non-musicians

Purpose: This study is to investigate whether Cantonese-speaking musicians may show stronger CP than Cantonese-speaking non-musicians in perceiving pitch directions generated based on Mandarin tones. It also aims to examine whether musicians may be more effective in processing stimuli and more sensitive to subtle differences caused by vowel quality.

Methods: Cantonese-speaking musicians and non-musicians performed a categorical identification and a discrimination task on rising and falling continua of fundamental frequency generated based on Mandarin level, rising and falling tones on two vowels with nine duration values.

Results: Cantonese-speaking musicians exhibited a stronger categorical perception (CP) of pitch contours than non-musicians based on the identification and discrimination tasks. Compared to non-musicians, musicians were also more sensitive to the change of stimulus duration and to the intrinsic F₀ in pitch perception in pitch processing.

Conclusion: The CP was strengthened due to musical experience and musicians benefited more from increased stimulus duration and were more efficient in pitch processing. Musicians might be able to better use the extra time to form an auditory representation with more acoustic details. Even with more efficiency in pitch processing, musicians' ability to detect subtle pitch changes caused by intrinsic F₀ was not undermined, which is likely due to their superior ability to process temporal information. These results thus suggest musicians may have a great advantage in learning tones of a second language.

The Melody of Speech: What the Melodic Perception of Speech Reveals about Language Performance and Musical Abilities

Research has shown that melody not only plays a crucial role in music but also in language acquisition processes. Evidence has been provided that melody helps in retrieving, remembering, and memorizing new language material, while relatively little is known about whether individuals who perceive speech as more melodic than others also benefit in the acquisition of oral languages. In this investigation, we wanted to show which impact the subjective melodic perception of speech has on the pronunciation of unfamiliar foreign languages. We tested 86 participants for how melodic they perceived five unfamiliar languages, for their ability to repeat and pronounce the respective five languages, for their musical abilities, and for their short-term memory (STM). The results revealed that 59 percent of the variance in the language pronunciation tasks could be explained by five predictors: the number of foreign languages spoken, short-term memory capacity, tonal aptitude, melodic singing ability, and how melodic the languages appeared to the participants. Group comparisons showed that individuals who perceived languages as more melodic performed significantly better in all language tasks than those who did not. However, even though we expected musical measures to be related to the melodic perception of foreign languages, we could only detect some correlations to rhythmical and tonal musical aptitude. Overall, the findings of this investigation add a new dimension to language research, which shows that individuals who perceive natural languages to be more melodic than others also retrieve and pronounce utterances more accurately.

A domain-general perspective on the role of the basal ganglia in language and music: Benefits of music therapy for the treatment of aphasia

In addition to cortical lesions, mounting evidence on the links between language and the subcortical regions suggests that subcortical lesions may also lead to the emergence of aphasic symptoms. In this paper, by emphasizing the domain-general function of the basal ganglia in both language and music, we highlight that rhythm processing, the function of temporal prediction, motor programming and execution, is an important shared mechanism underlying the treatment of non-fluent aphasia with music therapy. In support of this, we conduct a literature review on the music therapy treating aphasia. The results show that rhythm processing plays a key role in Melodic Intonation Therapy in the rehabilitation of non-fluent aphasia patients with lesions on the basal ganglia. This paper strengthens the correlation between the basal ganglia lesions and language deficits, and provides support to the direction of taking advantage of rhythm as an important point in music therapy in clinical studies.

Face recognition and memory in congenital amusia

Congenital amusia, commonly known as tone deafness, is a lifelong impairment of music perception and production. It remains a question of debate whether the impairments in musical domain observed in congenital amusia are paralleled in other non-musical perceptual abilities. Using behavioral measures in two experiments, the current study explored face perception and memory in congenital amusics. Both congenital amusics and matched controls performed a face perception task (Experiment 1) and an old/novel object memory task (for both faces and houses, Experiment 2). The results showed that the congenital amusic group had significantly slower reaction times than that in matched control group when identifying whether two faces presented together were the same or different. For different face-pairs, the deficit was greater for upright faces compared with inverted faces. For object memory task, the congenital amusic group also showed worse memory performance than the control group. The results of the present study suggest that the impairment attributed to congenital amusia is not only limited to music, but also extends to visual perception and visual memory domain.

Tracking Training-Related Plasticity by Combining fMRI and DTI: The Right Hemisphere Ventral Stream Mediates Musical Syntax Processing

As a functional homolog for left-hemispheric syntax processing in language, neuroimaging studies evidenced involvement of right prefrontal regions in musical syntax processing, of which underlying white matter connectivity remains unexplored so far. In the current experiment, we investigated the underlying pathway architecture in subjects with 3 levels of musical expertise. Employing diffusion tensor imaging tractography, departing from seeds from our previous functional magnetic resonance imaging study on music syntax processing in the same participants, we identified a pathway in the right ventral stream that connects the middle temporal lobe with the inferior frontal cortex via the extreme capsule, and corresponds to the left hemisphere ventral stream, classically attributed to syntax processing in language comprehension. Additional morphometric consistency analyses allowed dissociating tract core from more dispersed fiber portions. Musical expertise related to higher tract consistency of the right ventral stream pathway. Specifically, tract consistency in this pathway predicted the sensitivity for musical syntax violations. We conclude that enduring musical practice sculpts ventral stream architecture. Our results suggest that training-related pathway plasticity facilitates the right hemisphere ventral stream information transfer, supporting an improved sound-to-meaning mapping in music.

Music and the Meeting of Human Minds

Over tens of thousands of years of human genetic and cultural evolution, many types and varieties of music and language have emerged; however, the fundamental components of each of these modes of communication seem to be common to all human cultures and social groups. In this brief review, rather than focusing on the development of different musical techniques and practices over time, the main issues addressed here concern: (i) when, and speculations as to why, modern Homo sapiens evolved musical behaviors, (ii) the evolutionary relationship between music and language, and (iii) why humans, perhaps unique among all living species, universally continue to possess two complementary but distinct communication streams. Did music exist before language, or vice versa, or was there a common precursor that in some way separated into two distinct yet still overlapping systems when cognitively modern H. sapiens evolved? A number of theories put forward to explain the origin and persistent universality of music are considered, but emphasis is given, supported by recent neuroimaging, physiological, and psychological findings, to the role that music can play in promoting trust, altruistic behavior, social bonding, and cooperation within groups of culturally compatible but not necessarily genetically related humans. It is argued that, early in our history, the unique socializing and harmonizing power of music acted as an essential counterweight to the new and evolving sense of self, to an emerging sense of individuality and mortality that was linked to the development of an advanced cognitive capacity and articulate language capability.

Audiovisual Interval Size Estimation Is Associated with Early Musical Training

Although pitch is a fundamental attribute of auditory perception, substantial individual differences exist in our ability to perceive differences in pitch. Little is known about how these individual differences in the auditory modality might affect crossmodal processes such as audiovisual perception. In this study, we asked whether individual differences in pitch perception might affect audiovisual perception, as it relates to age of onset and number of years of musical training. Fifty-seven subjects made subjective ratings of interval size when given point-light displays of audio, visual, and audiovisual stimuli of sung intervals. Audiovisual stimuli were divided into congruent and incongruent (audiovisual-mismatched) stimuli. Participants’ ratings correlated strongly with interval size in audio-only, visual-only, and audiovisual-congruent conditions. In the audiovisual-incongruent condition, ratings correlated more with audio than with visual stimuli, particularly for subjects who had better pitch perception abilities and higher nonverbal IQ scores. To further investigate the effects of age of onset and length of musical training, subjects were divided into musically trained and untrained groups. Results showed that among subjects with musical training, the degree to which participants’ ratings correlated with auditory interval size during incongruent audiovisual perception was correlated with both nonverbal IQ and age of onset of musical training. After partialing out nonverbal IQ, pitch discrimination thresholds were no longer associated with incongruent audio scores, whereas age of onset of musical training remained associated with incongruent audio scores. These findings invite future research on the developmental effects of musical training, particularly those relating to the process of audiovisual perception.

Enhanced cognitive and perceptual processing: a computational basis for the musician advantage in speech learning

Long-term music training can positively impact speech processing. A recent framework developed to explain such cross-domain plasticity posits that music training-related advantages in speech processing are due to shared cognitive and perceptual processes between music and speech. Although perceptual and cognitive processing advantages due to music training have been independently demonstrated, to date no study has examined perceptual and cognitive processing within the context of a single task. The present study examines the impact of long-term music training on speech learning from a rigorous, computational perspective derived from signal detection theory. Our computational models provide independent estimates of cognitive and perceptual processing in native English-speaking musicians (n = 15, mean age = 25 years) and non-musicians (n = 15, mean age = 23 years) learning to categorize non-native lexical pitch patterns (Mandarin tones). Musicians outperformed non-musicians in this task. Model-based analyses suggested that musicians shifted from simple unidimensional decision strategies to more optimal multidimensional (MD) decision strategies sooner than non-musicians. In addition, musicians used optimal decisional strategies more often than non-musicians. However, musicians and non-musicians who used MD strategies showed no difference in performance. We estimated parameters that quantify the magnitude of perceptual variability along two dimensions that are critical for tone categorization: pitch height and pitch direction. Both musicians and non-musicians showed a decrease in perceptual variability along the pitch height dimension, but only musicians showed a significant reduction in perceptual variability along the pitch direction dimension. Notably, these advantages persisted during a generalization phase, when no feedback was provided. These results provide an insight into the mechanisms underlying the musician advantage observed in non-native speech learning.

The impact of musical training and tone language experience on talker identification

Listeners can use pitch changes in speech to identify talkers. Individuals exhibit large variability in sensitivity to pitch and in accuracy perceiving talker identity. In particular, people who have musical training or long-term tone language use are found to have enhanced pitch perception. In the present study, the influence of pitch experience on talker identification was investigated as listeners identified talkers in native language as well as non-native languages. Experiment 1 was designed to explore the influence of pitch experience on talker identification in two groups of individuals with potential advantages for pitch processing: musicians and tone language speakers. Experiment 2 further investigated individual differences in pitch processing and the contribution to talker identification by testing a mediation model. Cumulatively, the results suggested that (a) musical training confers an advantage for talker identification, supporting a shared resources hypothesis regarding music and language and (b) linguistic use of lexical tones also increases accuracy in hearing talker identity. Importantly, these two types of hearing experience enhance talker identification by sharpening pitch perception skills in a domain-general manner.

Electrophysiological evidence for a specific neural correlate of musical violation expectation in primary-school children

The majority of studies on music processing in children used simple musical stimuli. Here, primary schoolchildren judged the appropriateness of musical closure in expressive polyphone music, while high-density electroencephalography was recorded. Stimuli ended either regularly or contained refined in-key harmonic transgressions at closure. The children discriminated the transgressions well above chance. Regular and transgressed endings evoked opposite scalp voltage configurations peaking around 400ms after stimulus onset with bilateral frontal negativity for regular and centro-posterior negativity (CPN) for transgressed endings. A positive correlation could be established between strength of the CPN response and rater sensitivity (d-prime). We also investigated whether the capacity to discriminate the transgressions was supported by auditory domain specific or general cognitive mechanisms, and found that working memory capacity predicted transgression discrimination. Latency and distribution of the CPN are reminiscent of the N400, typically observed in response to semantic incongruities in language. Therefore our observation is intriguing, as the CPN occurred here within an intra-musical context, without any symbols referring to the external world. Moreover, the harmonic in-key transgressions that we implemented may be considered syntactical as they transgress structural rules. Such structural incongruities in music are typically followed by an early right anterior negativity (ERAN) and an N5, but not so here. Putative contributive sources of the CPN were localized in left pre-motor, mid-posterior cingulate and superior parietal regions of the brain that can be linked to integration processing. These results suggest that, at least in children, processing of syntax and meaning may coincide in complex intra-musical contexts.

Musical ability and non-native speech-sound processing are linked through sensitivity to pitch and spectral information

Is the observed link between musical ability and non-native speech-sound processing due to enhanced sensitivity to acoustic features underlying both musical and linguistic processing? To address this question, native English speakers (N = 118) discriminated Norwegian tonal contrasts and Norwegian vowels. Short tones differing in temporal, pitch, and spectral characteristics were used to measure sensitivity to the various acoustic features implicated in musical and speech processing. Musical ability was measured using Gordon's Advanced Measures of Musical Audiation. Results showed that sensitivity to specific acoustic features played a role in non-native speech-sound processing: Controlling for non-verbal intelligence, prior foreign language-learning experience, and sex, sensitivity to pitch and spectral information partially mediated the link between musical ability and discrimination of non-native vowels and lexical tones. The findings suggest that while sensitivity to certain acoustic features partially mediates the relationship between musical ability and non-native speech-sound processing, complex tests of musical ability also tap into other shared mechanisms.