Brain structural predispositions for music and language processing

[eng] It has been shown that music and language training can elicit plastic changes on brain structure and function bringing along behavioural benefits. For instance, musicians have been reported to have better auditory discrimination including pitch and speech-in-noise perception, motor-synchronization, verbal memory and general IQ than individuals without formal musical background. Also, bilinguals have shown higher executive function and attention-related abilities than monolinguals. Furthermore, altered functional and structural connectivity can be tracked to brain areas related to the activities most frequently performed by both musicians (instrumentalists and singers) and linguistic experts (such as bilinguals or professional phoneticians). While research in the last decade has devoted important effort to the study of brain plasticity, only a few investigations have addressed the connection between the initial functional or structural properties of brain networks related to auditory-motor function and subsequent language or musical training. Indeed, brain structural markers such as grey matter volume/density or white-matter diffusivity measurements from diffusion tensor imaging (DTI) data, as well as functional measurements from task- related activity or resting-state data from magnetic resonance imaging (MRI) or electroenceplhalography (EEG) have been demonstrated to correlate with consecutive performance and learning in the auditory-motor domain. The main goal of the present dissertation was twofold: we aimed to further the existing knowledge regarding brain plasticity elicited during putative sensitive periods and after long-term music practice, and to explore the white-matter pathways that predict linguistic or musical skills at baseline . Our secondary goals were to confirm previous findings regarding the brain structures involved in music and language processing, as well as to provide evidence of the benefits of usingstructural measurements and correlational analyses between imaging and behavioural data to study inter-individual differences. Study I focused on the comparison between professional pianists and non- musicians observing a complex pattern of increases and decreases in grey matter volume. In comparison to non-musician individuals, pianists showed greater grey matter volume in areas related to motor skill and the automatization of learned movements, as well as reinforcement learning and emotional processing. On the other hand, regions associated to sensorimotor control, score reading and auditory and musical perception presented a reduction in grey matter volume. Study II explored the relationship between white-matter structural properties of the arcuate fasciculus (AF) and the performance of native German speakers in a foreign- language (Hindi) sentence and word imitation task. We found that a greater left lateralization of the AF volume predicted performance on the imitation task. This result was confirmed by using not only a manual deterministic approach but also an automatic atlas-based fibre-reconstruction method, which in addition pointed out to a specific region in the anterior half of the left AF as the most related to imitation ability. Study III aimed to investigate whether the white-matter structural connectivity of the pathways previously described as targets for plasticity mechanisms in professional musicians predicted musical abilities in non-musicians. We observed that the white- matter microstructural organization of the right hemisphere pathways involved in motor-control (corticospinal tract) and auditory-motor transformations (AF) correlated with the performance of non-musician individuals during the initial stages of rhythmic and melodic learning. The present work confirmed the involvement of several brain structures previously described to display plastic effects associated to music and language training in the first stages of audio-motor learning. Furthermore, they challenge previous views regarding music-induced plasticity by showing that expertise is not always or uniquely correlated with increases in brain tissue. This raises the question of the role of efficiency mechanisms derived from professional-like practice. Most importantly, the results from these three studies converge in showing that a prediction-feedback-feedforward loop for auditory-motor processing may be crucially involved in both musical and language learning and skills. We thus suggest that brain auditory-motor systems previously described as participating in native language processing (cortical areas of the dorsal route for language processing and the AF that connects them) may also be recruited during exposure to new linguistic or musical material, being refined after sustained music practice.[spa] Estudios previos muestran que la formación musical y lingüística provoca cambios plásticos en las estructuras y funciones cerebrales, acompañándose también de beneficios conductuales. Por ejemplo, se ha descrito que los músicos poseen mejores habilidades de discriminación auditiva (incluyendo la percepción tonal y la discriminación del habla en un ambiente ruidoso), una mayor capacidad de sincronización motora, así como mejor memoria verbal y coeficiente intelectual general en comparación con personas sin formación musical. Paralelamente, los bilingües muestran mejores funciones ejecutivas y habilidades relacionadas con la atención en comparación con individuos monolingües. Además, las alteraciones en la conectividad cerebral funcional y estructural pueden ser rastreadas estudiando las áreas cerebrales relacionadas con las actividades más utilizadas por músicos (instrumentistas y cantantes) y expertos lingüísticos (como bilingües o fonetistas profesionales). Pese a que en la última década se han dedicado esfuerzos importantes en el campo de la investigación sobre la plasticidad cerebral, sólo unos pocos estudios han tratado de investigar la conexión entre las propiedades iniciales del cerebro, en cuanto a las funciones y estructuras que se relacionan con las funciones auditivo-motoras, y el posterior aprendizaje musical o del lenguaje. Sin embargo, los marcadores estructurales cerebrales, tales como volumen/densidad de materia gris o medidas de difusividad en la sustancia blanca a partir de datos de imagen del tensor de difusión, así como medidas funcionales de la actividad relacionada con una tarea o datos de resting-state (estado de reposo) obtenidos por resonancia magnética o electroencefalografía, han demostrado que pueden correlacionar con el rendimiento y el aprendizaje en el dominio auditivo- motor. En la presente tesis pretendíamos ampliar nuestro conocimiento en cuanto a la plasticidad cerebral obtenida durante los supuestos “períodos sensibles” y después de la práctica musical mantenida en el tiempo, por un lado, y explorar las vías de sustancia blanca que pueden predecir habilidades lingüísticas o musicales al inicio del aprendizaje, por otro lado. Como objetivos secundarios, queríamos confirmar resultados previos con respecto a las estructuras cerebrales involucradas en el procesamiento de la música y el lenguaje, así como apoyar el uso de mediciones estructurales y enfoques correlacionales (entre datos de neuroimagen y conductuales) para estudiar las diferencias inter- individuales. El Estudio I se centró en la comparación entre pianistas profesionales y no músicos, observando un complejo patrón de aumentos y disminuciones en el volumen de materia gris. En comparación con los individuos no músicos, los pianistas mostraron mayor volumen de sustancia gris en áreas relacionadas con la habilidad motora y la automatización de movimientos aprendidos, así como el aprendizaje a través del refuerzo y el procesamiento emocional, mientras que las regiones asociadas al control sensoriomotor, lectura de partituras y percepción auditiva y musical presentaron una reducción del volumen de materia gris. El Estudio II exploró la relación entre las propiedades estructurales de la materia blanca del fascículo arqueado (AF por sus siglas en inglés) y el rendimiento de hablantes nativos de alemán en una tarea de imitación de frases y palabras en una lengua extranjera (hindi). Encontramos que una mayor lateralización del volumen de AF hacia la izquierda predecía el desempeño en la tarea de imitación. Este resultado se confirmó utilizando no sólo un enfoque determinístico-manual sino también una reconstrucción automática (basada en atlas anatómicos) de las fibras de sustancia blanca que, además, señalaba una región específica en la mitad anterior del AF izquierdo como la más relacionada con las capacidades de imitación. El Estudio III tenía como objetivo investigar si la conectividad estructural de vías de sustancia blanca anteriormente descritas como dianas para los mecanismos de plasticidad en músicos profesionales, podría predecir las habilidades musicales en los no músicos. Se observó que la organización micro-estructural de la materia blanca en el hemisferio derecho en vías involucradas en el control motor (tracto corticoespinal) y en transformaciones auditivo-motoras (AF) correlacionaba con el desempeño de individuos no músicos en las etapas iniciales del aprendizaje rítmico y melódico. El presente trabajo ha confirmado la implicación en las primeras etapas del aprendizaje audio-motor de varias estructuras cerebrales que previamente habían mostrado efectos plásticos asociados al aprendizaje musical y del lenguaje. Además, estos resultados desafían las opiniones anteriores sobre la plasticidad inducida por la experiencia musical al demostrar que la experiencia no se correlaciona siempre ni únicamente con un aumento del tejido cerebral, y planteando así preguntas sobre los mecanismos de eficiencia derivados de la práctica musical a nivel profesional. Más importante aún es que los resultados de estos tres estudios convergen mostrando que un bucle de predicción–retroalimentación (feedback)–alimentación directa (feedforward) para el procesamiento auditivo-motor puede estar implicado de manera crucial tanto en el aprendizaje musical como en el aprendizaje de idiomas. Por tanto, sugerimos que los sistemas auditivo-motrices del cerebro, que previamente se habían descrito como participantes en el procesamiento del lenguaje nativo (áreas corticales involucradas en la vía dorsal para el procesamiento del lenguaje, y el AF, que las conecta) también pueden ser reclutados durante la exposición a material lingüístico o musical nuevo, siendo refinado tras años de práctica musical activ

Investigating the Functional and Structural Neural Correlates Associated With Dance Expertise

We investigated the structural and functional plasticity associated with dance expertise in a cross-sectional pilot study, comparing ballet dancers to controls. Using fMRI, the whole-brain functional activation maps of dancers and controls engaged in motor imagery of dance movements were compared. Controls were found to show greater activity in numerous regions relative to dancers, including in the superior frontal gyrus, hippocampus, and cerebellum. Anatomically, dancers exhibited greater cortical thickness in areas such as the inferior occipital gyrus, inferior frontal gyrus, and superior temporal gyrus. We also found years of dance training to be correlated with cortical thickness in various regions, including positive correlations being reported in the fusiform gyrus and parahippocampal gyrus. These preliminary results suggest that dance expertise is associated with a functional reorganization that corresponds to the reduced activity reported in other motor expertise groups, as well various putative changes in structure

The effect of practice and musical structure on pianists’ eye-hand span and visual monitoring

This study examines short-term improvement of music performances and oculomotor behaviour during four successive executions of a brief musical piece composed by Bartók, “Slovak Boys’ Dance”. Pianists (n=22) were allowed to practice for two minutes between each trial. Eye-tracking data were collected as well as MIDI information from pianists’ performances. Cognitive skills were assessed by a spatial memory test and a reading span test. Principal component analysis (PCA) enabled us to distinguish two axes, one associated with anticipation and the other with dependence/independence on written code. The effect of musical structure, determined by the emergence of different sections in the score, was observed in all the dependent variables selected from the PCA; we also observed the effect of practice on the number of fixations, the number of glances at the keyboard (GAK) and the awareness span. Pianist expertise was associated with fewer fixations and GAK, better anticipation capacities and more effective strategies for visual monitoring of motor movements. The significant correlations observed between the reading span test and GAK duration highlight the challenge of working memory involvement during music reading.

MUSIC TRAINING AS A NEURO-COGNITIVE PROTECTOR FOR BRAIN AGING: COGNITIVE AND NEUROPSYCHOLOGICAL PROFILES IN PROFESSIONAL MUSICIANS

The proportion of older adults living with cognitive impairments is increasing rapidly. This shift will likely increase mortality rates, reduce perceived quality of life, and cause economic burden to patients and health care systems. Currently evidence of highly effective and noninvasive interventions that prevent or slow the onset of cognitive impairment are limited. This study aims to better understand what drives cognitive aging variability among musicians versus non-musicians. Music playing has been shown to improve brain and cognitive functions by engaging networks of brain areas, simultaneously involving cortical mechanisms associated with executive, high-level cognitive and motor functions, and multiple sensory systems. Literature suggests strong correlations between cognition and music ability. However, studies in the past have not concretely operationalized music training. Here we test the general hypothesis that music training improves neural mechanisms associated with core cognitive functions (e.g. working-memory and attention). A multi-source study was designed to control level of music involvement and genre by examining professional, classically trained orchestral musicians, establishing cognitive and neuropsychological profiles in an effort to better understand the potential for music training to protect older adults from cognitive decline. Specific hypotheses involved attentional inhibition theory and increased ability of musicians to perform attention and working memory tasks. Twenty-nine professional musicians were recruited who completed five neuropsychological exams. The scalp electrophysiological signals from 14 channels were recorded wirelessly while each musician performed a modified delayed match-to-sample task, imagination of music playing, and resting states. Musicians completed neuropsychological screening (MoCA) a music and life span questionnaire as well. Musicians tested above normative ranges in cognitive ability indicated through MoCA. Musicians’ scores were compared with average or normative scores of participants at similar ages in previous studies using the same measures and current musicians performed significantly faster and more accurately on four of five neuropsychological measures. Regression and ANCOVA showed strong positive correlations between theta oscillation in bilateral frontal sites (F3, F4) and both number of years of private music lessons and number of hours of music practice. Correlations between EEG recordings taken during music imagination exercise at posterior (01, 02) sites and the number of years of private music lessons participants took, the age participant started to take music lessons and the number of years they played their musical instrument were found. Current new findings reveal that professional musician’s cognitive scores and neural activity are associated with superior cognitive ability via enhancement of neural mechanisms of current target material and inhibition of distractions. Music training is apromising noninvasive method to control cognitive challenge, which merits further research to determine how it can be used as a beneficial cognitive training method for aging individuals. Future studies should examine neuro-cognitive differences between professional musicians and individuals with lower levels of music involvement to examine dose effects of music or the amount of music needed to protect aging adults from cognitive decline

Revisiting the conditioning variables of neuroplasticity induced by music training

Music training changes the brain both anatomically and functionally, where some variables conditioning the neuroplasticity. Here is a review of them, which include recent research in the neuroscience of music field. These variables are individual differences, sex, laterality, absolute pitch, instrument family, type of musical training received by the performer, training details –such as the intensity or age of onset, for example–, in addition to other environmental and genetic factors.El entrenamiento musical reiterado puede modificar el cerebro tanto anatómicamente como en su función, pero existen una serie de variables que condicionan la neuroplasticidad. Este texto realiza una revisión actualizada sobre ellas, revisitándolas incluyendo las últimas investigaciones en el campo de la neurociencia de la música. Entre las variables de interés, se encuentran las diferencias individuales, el sexo, la lateralidad manual, la habilidad de oído absoluto, el instrumento que se interpreta, el tipo de formación musical que recibe el intérprete, las particularidades del entrenamiento –como la intensidad del mismo o la edad de inicio, por ejemplo–, además de otros factores ambientales y genéticos

Musical instrument training program improves verbal memory and neural efficiency in novice older adults

楽器訓練で高齢者の認知機能が向上することを確認 --訓練による脳活動の変化を高齢者で初報告--. 京都大学プレスリリース. 2020-12-24.Previous studies indicate that musical instrument training may improve the cognitive function of older adults. However, little is known about the neural origins of training‐related improvement in cognitive function. Here, we assessed the effects of instrumental training program on cognitive functions and neural efficiency in musically naïve older adults (61–85 years old). Participants were assigned to either the intervention group, which received a 4‐month instrumental training program using keyboard harmonica, or a control group without any alternative training. Cognitive measurements and functional magnetic resonance imaging during visual working memory (VWM) task were administered before and after the intervention in both groups. Behavioral data revealed that the intervention group significantly improved memory performance on the test that measures verbal recall compared to the control group. Neuroimaging data revealed that brain activation in the right supplementary motor area, left precuneus, and bilateral posterior cingulate gyrus (PCgG) during the VWM task decreased after instrumental training only in the intervention group. Task‐related functional connectivity (FC) analysis revealed that the intervention group showed decreased FC between the right PCgG and left middle temporal gyrus, and between the left putamen and right superior temporal gyrus (lPu‐rSTG) during a VWM task after the intervention. Furthermore, a greater improvement in memory performance in the intervention group was associated with a larger reduction in lPu‐rSTG FC, which might be interpreted as improved neural efficiency. Our results indicate that the musical instrument training program may contribute to improvements in verbal memory and neural efficiency in novice older adults

Performing Music on Stage: The Role of the Hippocampus in Expert Memory and Culture

This overview chapter discusses memory functions from the viewpoint of the performing arts. ‘Playing music by heart’ is taken as an example to illustrate the role of the hippocampus in acquiring and expressing expert memory. Many more aspects depend on hippocampal mechanisms beyond declarative memory, for example, motor sequence learning, phrase boundary processing, and time-precise sequence recall. In consequence, changes in size and/or functional activity also occur in the hippocampus, known as hippocampal plasticity. Whenever the to-be-remembered items have to be stabilized even further, certain mnemonic strategies are effective, of which the oldest is the (hippocampal-based) method of loci, using visuospatial imagery. Mnemonic techniques also play a role in ethnomusicology. For example, North Indian tabla players combine drum patterns with certain onomatopoeic syllables to keep on track when performances last over hours. The value of memory processes is also discussed from a sociocultural perspective. Since priests, teachers, heads of tribes, and many others are explicit carriers of internalized knowledge, they help preserve oral traditions and culture. A special emphasis is on the accurate memorization of the Quran in Arabic, revealing that internalized sacred knowledge acquired through learning by rote can serve as a moral compass for the individual

Neural Correlates of Multisensory Integration and the Role of Musical Experience

A large body of experimental research demonstrates that environments and behavioral experiences can affect cognitive performance. There has been increasing interest in the influence of musical experience on normal neuronal functioning over the past decade. However, much of this research has failed to target specific neural activity as indicators of cognitive function. One such measure of neural activity is the mismatch negativity (MMN), an event-related potential (ERP) that occurs in response to the presentation of a deviant stimulus in a sequence of repeated stimuli. The primary aim of the current study was to explore the influence of musical experience on sensory integration as measured using the MMN ERP. It was predicted that (1) the MMN could be used as a measure of multisensory integration and (2) that this measure of multisensory integration would correlate with an individual’s level of musical experience (as determined by pre-study measurements)

Musical Performance in Adolescents with ADHD, ADD and Dyslexia—Behavioral and Neurophysiological Aspects

Research has shown that dyslexia and attention deficit (hyperactivity) disorder (AD(H)D) are characterized by specific neuroanatomical and neurofunctional differences in the auditory cortex. These neurofunctional characteristics in children with ADHD, ADD and dyslexia are linked to distinct differences in music perception. Group-specific differences in the musical performance of patients with ADHD, ADD and dyslexia have not been investigated in detail so far. We investigated the musical performance and neurophysiological correlates of 21 adolescents with dyslexia, 19 with ADHD, 28 with ADD and 28 age-matched, unaffected controls using a music performance assessment scale and magnetoencephalography (MEG). Musical experts independently assessed pitch and rhythmic accuracy, intonation, improvisation skills and musical expression. Compared to dyslexic adolescents, controls as well as adolescents with ADHD and ADD performed better in rhythmic reproduction, rhythmic improvisation and musical expression. Controls were significantly better in rhythmic reproduction than adolescents with ADD and scored higher in rhythmic and pitch improvisation than adolescents with ADHD. Adolescents with ADD and controls scored better in pitch reproduction than dyslexic adolescents. In pitch improvisation, the ADD group performed better than the ADHD group, and controls scored better than dyslexic adolescents. Discriminant analysis revealed that rhythmic improvisation and musical expression discriminate the dyslexic group from controls and adolescents with ADHD and ADD. A second discriminant analysis based on MEG variables showed that absolute P1 latency asynchrony |R-L| distinguishes the control group from the disorder groups best, while P1 and N1 latencies averaged across hemispheres separate the control, ADD and ADHD groups from the dyslexic group. Furthermore, rhythmic improvisation was negatively correlated with auditory-evoked P1 and N1 latencies, pointing in the following direction: the earlier the P1 and N1 latencies (mean), the better the rhythmic improvisation. These findings provide novel insight into the differences between music processing and performance in adolescents with and without neurodevelopmental disorders. A better understanding of these differences may help to develop tailored preventions or therapeutic interventions