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

Abstract

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.

Keywords: complex trait genetics; individual differences; musicality; neural endophenotypes; pleiotropy; speech and language development.

Figure 1.

Schematic illustration of the proposed role of musicality in language across the lifespan, showing the curvilinear relationship of language abilities across ages, moderated by relatively higher and lower levels of overall musicality (e.g., musical abilities, engagement, and environments). We propose that individuals with relatively higher musicality on a spectrum of typical individual differences (solid curved line) will have enhanced language abilities and/or steeper developmental trajectories in early stages of life compared to those with relatively lower musicality, or impairments in musical abilities (dashed curved line). Similarly, we propose that in adulthood and in the context of aging, those with relatively higher musicality will experience extended maintenance of peak performance, and slower decline in speech-language function later in life (e.g., efficiency of their speech perception in noise).

Figure 2.

The MAPLE framework. Genetic pleiotropy is illustrated by overlapping maple leaves (left) signifying shared polygenic architecture influencing musicality and language traits. Shared genes influencing musicality and language are thought to exert influence on cascading biological processing including development, structure, and functioning of the brain, and nervous system functions relevant for musical and language traits such as auditory processing, and sensorimotor coordination (center top). Alongside genetic influences on these neural endophenotypes, polygenic influences on musicality and language are also thought to influence key environmental factors such as social relationships, and home musical and language environments (center bottom). Thus, genetic pleiotropy (left) is thought to be a root biological mechanism underlying the observable phenotypic associations between musical and language traits widespread in the literature (right). The MAPLE framework’s predictions can be tested by examining (a) polygenic architecture underlying musicality and language traits (left), (b) polygenic architecture and heritability of relevant neural endophenotypes, and of home and school musical and linguistic environments (center top and bottom, respectively), and (c) phenotypic variation in musical and language traits in broad populations, and cross-trait associations (right). Arrows illustrate the directions of influence between genes, neural endophenotypes, environment, and behavior.

Figure 3.

Bibliometric mapping based on co-occurring music and language terms. Figure shows the major clusters of research areas emerging when 60% of the most relevant terms shared between published articles are shown. Search terms included common terms associated with music and language science.

Figure 4.

Figure mapping “individual difference” and “musical training” within bibliographic clusters. When the term “individual difference” occurred in publications, it was most commonly accompanied by the terms “speech perception,” “test,” “child,” “skill,” “year,” “processing,” while “musical training” was linked to a much wider array of terms representing its more widespread use in the music and language science literature. Plurals in the figure are encompassed by singular forms (e.g., “individual difference” also comprises “individual differences”).

Figure 5.

Studies examining within-sample associations between musicality and language traits. Each bubble corresponds to a single study, and studies are grouped by which broad language-related construct(s) they examined (e.g., speech perception, grammatical skills, reading-related abilities, or multiple) on the horizontal axis, and by which musicality construct(s) they examined (e.g., tonal-melodic or rhythm skills) on the vertical axis. Studies spanning multiple musicality or language traits are represented by multiple bubbles as relevant.