Language Ability Predicts Cortical Structure and Covariance in Boys with Autism Spectrum Disorder.

There is significant clinical heterogeneity in language and communication abilities of individuals with Autism Spectrum Disorders (ASD). However, no consistent pathology regarding the relationship of these abilities to brain structure has emerged. Recent developments in anatomical correlation-based approaches to map structural covariance networks (SCNs), combined with detailed behavioral characterization, offer an alternative for studying these relationships. In this study, such an approach was used to study the integrity of SCNs of cortical thickness and surface area associated with language and communication, in 46 high-functioning, school-age children with ASD compared with 50 matched, typically developing controls (all males) with IQ > 75. Findings showed that there was alteration of cortical structure and disruption of fronto-temporal cortical covariance in ASD compared with controls. Furthermore, in an analysis of a subset of ASD participants, alterations in both cortical structure and covariance were modulated by structural language ability of the participants, but not communicative function. These findings indicate that structural language abilities are related to altered fronto-temporal cortical covariance in ASD, much more than symptom severity or cognitive ability. They also support the importance of better characterizing ASD samples while studying brain structure and for better understanding individual differences in language and communication abilities in ASD.

Auditory Pitch Perception in Autism Spectrum Disorder Is Associated With Nonverbal Abilities.

Atypical sensory perception and heterogeneous cognitive profiles are common features of autism spectrum disorder (ASD). However, previous findings on auditory sensory processing in ASD are mixed. Accordingly, auditory perception and its relation to cognitive abilities in ASD remain poorly understood. Here, children with ASD, and age- and intelligence quotient (IQ)-matched typically developing children, were tested on a low- and a higher level pitch processing task. Verbal and nonverbal cognitive abilities were measured using the Wechsler's Abbreviated Scale of Intelligence. There were no group differences in performance on either auditory task or IQ measure. However, there was significant variability in performance on the auditory tasks in both groups that was predicted by nonverbal, not verbal skills. These results suggest that auditory perception is related to nonverbal reasoning rather than verbal abilities in ASD and typically developing children. In addition, these findings provide evidence for preserved pitch processing in school-age children with ASD with average IQ, supporting the idea that there may be a subgroup of individuals with ASD that do not present perceptual or cognitive difficulties. Future directions involve examining whether similar perceptual-cognitive relationships might be observed in a broader sample of individuals with ASD, such as those with language impairment or lower IQ.

Atypical functional brain connectivity during rest in autism spectrum disorders.

OBJECTIVE: Connectivity atypicalities in autism spectrum disorders (ASD) have been extensively proposed. The default mode network (DMN) is critical in this study, given the insight it provides for long-distance connectivity, and the importance of regions in this network for introspection and social emotion processing, areas affected in ASD. However, study of this network has largely been limited to adults; research earlier in development is lacking. The objective of this study was to examine DMN connectivity in children/adolescents with ASD. METHODS: A total of 115 children/adolescents, aged 6 to 17 years (71 males with ASD and 44 group age-matched TD males) were included in these analyses. We examined group differences in (1) functional connectivity between the posterior cingulate cortex and regions across the brain, (2) connectivity within the DMN as a function of age and intelligence quotient (IQ), and (3) the association between DMN connectivity and empathic accuracy. RESULTS: Individuals with ASD, relative to controls, showed either stronger or weaker connectivity between the posterior cingulate cortex (PCC) and DMN regions, depending on the region, but also showed stronger connectivity with non-DMN regions. A significant group-by-age interaction was observed in functional connectivity between the PCC and medial prefrontal cortex; connectivity increased with age in controls, but decreased in individuals with ASD. No effects of IQ were found. There was a significant group difference in the relation between DMN connectivity and empathic accuracy. INTERPRETATION: Differences in functional connectivity may suggest the presence of neural atypicalities that impact the development of typical connectivity in ASD. In addition to affecting DMN dynamics, these atypicalities may also impact social-cognitive abilities.

Sensorimotor integration is enhanced in dancers and musicians.

Studying individuals with specialized training, such as dancers and musicians, provides an opportunity to investigate how intensive practice of sensorimotor skills affects behavioural performance across various domains. While several studies have found that musicians have improved motor, perceptual and sensorimotor integration skills compared to untrained controls, fewer studies have examined the effect of dance training on such skills. Moreover, no study has specifically compared the effects of dance versus music training on perceptual or sensorimotor performance. To this aim, in the present study, expert dancers, expert musicians and untrained controls were tested on a range of perceptual and sensorimotor tasks designed to discriminate performance profiles across groups. Dancers performed better than musicians and controls on a dance imitation task (involving whole-body movement), but musicians performed better than dancers and controls on a musical melody discrimination task as well as on a rhythm synchronization task (involving finger tapping). These results indicate that long-term intensive dance and music training are associated with distinct enhancements in sensorimotor skills. This novel work advances knowledge of the effects of long-term dance versus music training and has potential applications in therapies for motor disorders.

Brain activity is related to individual differences in the number of items stored in auditory short-term memory for pitch: evidence from magnetoencephalography.

We used magnetoencephalography (MEG) to examine brain activity related to the maintenance of non-verbal pitch information in auditory short-term memory (ASTM). We focused on brain activity that increased with the number of items effectively held in memory by the participants during the retention interval of an auditory memory task. We used very simple acoustic materials (i.e., pure tones that varied in pitch) that minimized activation from non-ASTM related systems. MEG revealed neural activity in frontal, temporal, and parietal cortices that increased with a greater number of items effectively held in memory by the participants during the maintenance of pitch representations in ASTM. The present results reinforce the functional role of frontal and temporal cortices in the retention of pitch information in ASTM. This is the first MEG study to provide both fine spatial localization and temporal resolution on the neural mechanisms of non-verbal ASTM for pitch in relation to individual differences in the capacity of ASTM. This research contributes to a comprehensive understanding of the mechanisms mediating the representation and maintenance of basic non-verbal auditory features in the human brain.

Response to Music-Mediated Intervention in Autistic Children with Limited Spoken Language Ability.

PURPOSE: Autistic children with limited spoken language ability (LSLA) often do not respond to traditional interventions, reducing their social inclusion. It is essential to identify effective interventions, and sensitive measures to track their intervention response. METHODS: Using data from an RCT comparing music-mediated and play-based interventions, we investigated the impact of spoken language ability on outcomes, and measured response to intervention through natural language sample measures. RESULTS: Children with lower verbal IQ, relative to higher verbal IQ, made some greater gains over the course of music-mediated intervention. Natural language samples were helpful in characterizing communication and tracking change. CONCLUSION: Music-mediated interventions hold promise as effective interventions for autistic children with LSLA. Natural language samples are robust in characterizing this subgroup.

Does music training improve inhibition control in children? A systematic review and meta-analysis.

Inhibition control is an essential executive function during children's development, underpinning self-regulation and the acquisition of social and language abilities. This executive function is intensely engaged in music training while learning an instrument, a complex multisensory task requiring monitoring motor performance and auditory stream prioritization. This novel meta-analysis examined music-based training on inhibition control in children. Records from 1980 to 2023 yielded 22 longitudinal studies with controls (N = 1734), including 8 RCTs and 14 others. A random-effects meta-analysis showed that music training improved inhibition control (moderate-to-large effect size) in the RCTs and the superset of twenty-two longitudinal studies (small-to-moderate effect size). Music training plays a privileged role compared to other activities (sports, visual arts, drama) in improving children's executive functioning, with a particular effect on inhibition control. We recommend music training for complementing education and as a clinical tool focusing on inhibition control remediation (e.g., in autism and ADHD).

Structural brain changes linked to delayed first language acquisition in congenitally deaf individuals.

Early language experience is essential for the development of a high level of linguistic proficiency in adulthood and in a recent functional Magnetic Resonance Imaging (fMRI) experiment, we showed that a delayed acquisition of a first language results in changes in the functional organization of the adult brain (Mayberry et al., 2011). The present study extends the question to explore if delayed acquisition of a first language also modulates the structural development of the brain. To this end, we carried out anatomical MRI in the same group of congenitally deaf individuals who varied in the age of acquisition of a first language, American Sign Language -ASL (Mayberry et al., 2011) and used a neuroanatomical technique, Voxel-Based Morphometry (VBM), to explore changes in gray and white matter concentrations across the brain related to the age of first language acquisition. The results show that delayed acquisition of a first language is associated with changes in tissue concentration in the occipital cortex close to the area that has been found to show functional recruitment during language processing in these deaf individuals with a late age of acquisition. These findings suggest that a lack of early language experience affects not only the functional but also the anatomical organization of the brain.

Functional MRI evidence of an abnormal neural network for pitch processing in congenital amusia.

Congenital amusia (tone deafness) is a lifelong disorder that prevents typically developing individuals from acquiring basic musical skills. Electrophysiological evidence indicates that congenital amusia is related to a musical pitch deficit that does not seem to arise from a dysfunction of the auditory cortex but rather from an anomaly along a frontotemporal auditory pathway. In order to better localize the neural basis of this pitch disorder, here we conducted a functional magnetic resonance imaging (fMRI) study. Congenital amusic adults and "musically intact" controls were scanned while passively listening to pure-tone melodic-like sequences in which the pitch distance between consecutive tones was varied parametrically. In both amusics and controls, brain activity increased as a function of increasing pitch distance, even for fine pitch changes, in both the left and right auditory cortices. These results support prior electrophysiological work showing that the auditory cortex of amusic individuals responds normally to pitch. In contrast, the right inferior frontal gyrus showed an abnormal deactivation in the amusic group, as well as reduced connectivity with the auditory cortex as compared with controls. These fMRI data are highly consistent with previous gray and white matter anomalies found in amusics in the auditory and inferior frontal cortices, as well as reduced white matter connections between these 2 regions.

Auditory global-local processing: effects of attention and musical experience.

In vision, global (whole) features are typically processed before local (detail) features ("global precedence effect"). However, the distinction between global and local processing is less clear in the auditory domain. The aims of the present study were to investigate: (i) the effects of directed versus divided attention, and (ii) the effect musical training on auditory global-local processing in 16 adult musicians and 16 non-musicians. Participants were presented with short nine-tone melodies, each comprised of three triplet sequences (three-tone units). In a "directed attention" task, participants were asked to focus on either the global or local pitch pattern and had to determine if the pitch pattern went up or down. In a "divided attention" task, participants judged whether the target pattern (up or down) was present or absent. Overall, global structure was perceived faster and more accurately than local structure. The global precedence effect was observed regardless of whether attention was directed to a specific level or divided between levels. Musicians performed more accurately than non-musicians overall, but non-musicians showed a more pronounced global advantage. This study provides evidence for an auditory global precedence effect across attention tasks, and for differences in auditory global-local processing associated with musical experience.

Joint engagement and movement: Active ingredients of a music-based intervention with school-age children with autism.

BACKGROUND: The effectiveness of music-based interventions (MI) in autism has been attested for decades. Yet, there has been little empirical investigation of the active ingredients, or processes involved in music-based interventions that differentiate them from other approaches. OBJECTIVES: Here, we examined whether two processes, joint engagement and movement, which have previously been studied in isolation, contribute as important active ingredients for the efficacy of music-based interventions. METHODS: In two separate analyses, we investigated whether (1) joint engagement with the therapist, measured using a coding scheme verified for reliability, and (2) movement elicited by music-making, measured using a computer-vision technique for quantifying motion, may drive the benefits previously observed in response to MI (but not a controlled non-MI) in children with autism. RESULTS: Compared to a non-music control intervention, children and the therapist in MI spent more time in triadic engagement (between child, therapist, and activity) and produced greater movement, with amplitude of motion closely linked to the type of musical instrument. CONCLUSIONS: Taken together, these findings provide initial evidence of the active ingredients of music-based interventions in autism.

Enhanced Memory for Vocal Melodies in Autism Spectrum Disorder and Williams Syndrome.

Adults and children with typical development (TD) remember vocal melodies (without lyrics) better than instrumental melodies, which is attributed to the biological and social significance of human vocalizations. Here we asked whether children with autism spectrum disorder (ASD), who have persistent difficulties with communication and social interaction, and adolescents and adults with Williams syndrome (WS), who are highly sociable, even indiscriminately friendly, exhibit a memory advantage for vocal melodies like that observed in individuals with TD. We tested 26 children with ASD, 26 adolescents and adults with WS of similar mental age, and 26 children with TD on their memory for vocal and instrumental (piano, marimba) melodies. After exposing them to 12 unfamiliar folk melodies with different timbres, we required them to indicate whether each of 24 melodies (half heard previously) was old (heard before) or new (not heard before) during an unexpected recognition test. Although the groups successfully distinguished the old from the new melodies, they differed in overall memory. Nevertheless, they exhibited a comparable advantage for vocal melodies. In short, individuals with ASD and WS show enhanced processing of socially significant auditory signals in the context of music. LAY SUMMARY: Typically developing children and adults remember vocal melodies better than instrumental melodies. In this study, we found that children with Autistic Spectrum Disorder, who have severe social processing deficits, and children and adults with Williams syndrome, who are highly sociable, exhibit comparable memory advantages for vocal melodies. The results have implications for musical interventions with these populations.

Musical training shapes structural brain development.

The human brain has the remarkable capacity to alter in response to environmental demands. Training-induced structural brain changes have been demonstrated in the healthy adult human brain. However, no study has yet directly related structural brain changes to behavioral changes in the developing brain, addressing the question of whether structural brain differences seen in adults (comparing experts with matched controls) are a product of "nature" (via biological brain predispositions) or "nurture" (via early training). Long-term instrumental music training is an intense, multisensory, and motor experience and offers an ideal opportunity to study structural brain plasticity in the developing brain in correlation with behavioral changes induced by training. Here we demonstrate structural brain changes after only 15 months of musical training in early childhood, which were correlated with improvements in musically relevant motor and auditory skills. These findings shed light on brain plasticity and suggest that structural brain differences in adult experts (whether musicians or experts in other areas) are likely due to training-induced brain plasticity.

Neuroanatomical differences in brain areas implicated in perceptual and other core features of autism revealed by cortical thickness analysis and voxel-based morphometry.

Autism spectrum disorder is a complex neurodevelopmental variant thought to affect 1 in 166 [Fombonne (2003): J Autism Dev Disord 33:365-382]. Individuals with autism demonstrate atypical social interaction, communication, and repetitive behaviors, but can also present enhanced abilities, particularly in auditory and visual perception and nonverbal reasoning. Structural brain differences have been reported in autism, in terms of increased total brain volume (particularly in young children with autism), and regional gray/white matter differences in both adults and children with autism, but the reports are inconsistent [Amaral et al. (2008): Trends Neurosci 31:137-145]. These inconsistencies may be due to differences in diagnostic/inclusion criteria, and age and Intelligence Quotient of participants. Here, for the first time, we used two complementary magnetic resonance imaging techniques, cortical thickness analyses, and voxel-based morphometry (VBM), to investigate the neuroanatomical differences between a homogenous group of young adults with autism of average intelligence but delayed or atypical language development (often referred to as "high-functioning autism"), relative to a closely matched group of typically developing controls. The cortical thickness and VBM techniques both revealed regional structural brain differences (mostly in terms of gray matter increases) in brain areas implicated in social cognition, communication, and repetitive behaviors, and thus in each of the core atypical features of autism. Gray matter increases were also found in auditory and visual primary and associative perceptual areas. We interpret these results as the first structural brain correlates of atypical auditory and visual perception in autism, in support of the enhanced perceptual functioning model [Mottron et al. (2006): J Autism Dev Disord 36:27-43].

Unisensory and multisensory temporal processing in autism and dyslexia: A systematic review and meta-analysis.

This study presents a comprehensive systematic review and meta-analysis of temporal processing in autism spectrum disorder (ASD) and developmental dyslexia (DD), two neurodevelopmental disorders in which temporal processing deficits have been highly researched. The results provide strong evidence for impairments in temporal processing in both ASD (g = 0.48) and DD (g = 0.82), as measured by judgments of temporal order and simultaneity. In individual analyses, multisensory temporal processing was impaired for both ASD and DD, and unisensory auditory, visual and tactile processing were all impaired in DD. In ASD, speech stimuli showed moderate impairment effect sizes, whereas nonspeech stimuli showed small effects. Greater reading and spelling skills in DD were associated with greater temporal precision. Temporal deficits did not show changes with age in either disorder. In addition to more clearly defining temporal impairments in ASD and DD, the results highlight common and distinct patterns of temporal processing between these disorders. Deficits are discussed in relation to existing theoretical models, and recommendations are made for future research.

The descending motor tracts are different in dancers and musicians.

Long-term motor training, such as dance or gymnastics, has been associated with increased diffusivity and reduced fiber coherence in regions including the corticospinal tract. Comparisons between different types of motor experts suggest that experience might result in specific structural changes related to the trained effectors (e.g., hands or feet). However, previous studies have not segregated the descending motor pathways from different body-part representations in motor cortex (M1). Further, most previous diffusion tensor imaging studies used whole-brain analyses based on a single tensor, which provide poor information about regions where multiple white matter (WM) tracts cross. Here, we used multi-tensor probabilistic tractography to investigate the specific components of the descending motor pathways in well-matched groups of dancers, musicians and controls. To this aim, we developed a procedure to identify the WM regions below the motor representations of the head, hand, trunk and leg that served as seeds for tractography. Dancers showed increased radial diffusivity (RD) in comparison with musicians, in descending motor pathways from all the regions, particularly in the right hemisphere, whereas musicians had increased fractional anisotropy (FA) in the hand and the trunk/arm motor tracts. Further, dancers showed larger volumes compared to both other groups. Finally, we found negative correlations between RD and FA with the age of start of dance or music training, respectively, and between RD and performance on a melody task, and positive correlations between RD and volume with performance on a whole-body dance task. These findings suggest that different types of training might have different effects on brain structure, likely because dancers must coordinate movements of the entire body, whereas musicians focus on fewer effectors.

Pitch direction ability predicts melodic perception in autism.

Individuals with autism spectrum disorders (ASDs) often present atypical auditory perception. Previous work has reported both enhanced low-level pitch discrimination and superior abilities to detect local pitch structure on higher-level melodic tasks in ASD. However, it is unclear how low and high levels of auditory perception are related in ASD or typical development (TD), or how this relationship might change across development and stimulus presentation rates. To these aims, in the present study, children with ASD and TD were tested on a low-level pitch direction discrimination task and a high-level melodic global-local task. Groups performed similarly on both of these auditory tasks. Moreover, individual differences in low-level pitch direction ability predicted performance on the higher-level global-local task, with a stronger relationship in ASD. Age did not affect the relationship between low-level and high-level pitch performance in either ASD or TD. However, there was a more positive effect of age on the high-level global-local task performance in TD than ASD. Finally, there was no effect of stimulus rate on the relationship between low-level and high-level pitch performance in either group. These findings provide a better understanding of how perception is associated across levels of processing in ASD versus TD. This work helps to better understand individual differences in auditory perception and to refine ASD phenotypes.

Cortical thickness in congenital amusia: when less is better than more.

Congenital amusia (or tone deafness) is a lifelong disorder characterized by impairments in the perception and production of music. A previous voxel-based morphometry (VBM) study revealed that amusic individuals had reduced white matter in the right inferior frontal gyrus (IFG) relative to musically intact controls (Hyde et al., 2006). However, this VBM study also revealed associated increases in gray matter in the same right IFG region of amusics. The objective of the present study was to better understand this morphological brain anomaly by way of cortical thickness measures that provide a more specific measure of cortical morphology relative to VBM. We found that amusic subjects (n = 21) have thicker cortex in the right IFG and the right auditory cortex relative to musically intact controls (n = 26). These cortical thickness differences suggest the presence of cortical malformations in the amusic brain, such as abnormal neuronal migration, that may have compromised the normal development of a right frontotemporal pathway.

Evidence for the role of the right auditory cortex in fine pitch resolution.

The neural basis of human pitch perception is not fully understood. It has been argued that the auditory cortices in the two hemispheres are specialized, such that certain right auditory cortical regions have a relatively finer resolution in the frequency domain than homologous regions in the left auditory cortex, but this concept has not been tested directly. Here, we used functional magnetic resonance imaging (fMRI) to test this specific prediction. Healthy volunteers were scanned while passively listening to pure-tone melodic-like sequences in which the pitch distance between consecutive tones was varied in a parametric fashion. As predicted, brain activation in a region of right lateral auditory cortex, corresponding to the planum temporale, was linearly responsive to increasing pitch distance, even across the fine changes in pitch. In contrast, the BOLD signal at the homologous left cortical region was relatively constant as a function of pitch distance, except at the largest pitch change. The results support the model of relative hemispheric specialization and indicate that the right secondary auditory cortex has a finer pitch resolution than the left.