Publications by authors named "Sylvain Moreno"

49 Publications

A fast and fully-automated deep-learning approach for accurate hemorrhage segmentation and volume quantification in non-contrast whole-head CT.

Sci Rep 2020 11 9;10(1):19389. Epub 2020 Nov 9.

Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada.

This project aimed to develop and evaluate a fast and fully-automated deep-learning method applying convolutional neural networks with deep supervision (CNN-DS) for accurate hematoma segmentation and volume quantification in computed tomography (CT) scans. Non-contrast whole-head CT scans of 55 patients with hemorrhagic stroke were used. Individual scans were standardized to 64 axial slices of 128 × 128 voxels. Each voxel was annotated independently by experienced raters, generating a binary label of hematoma versus normal brain tissue based on majority voting. The dataset was split randomly into training (n = 45) and testing (n = 10) subsets. A CNN-DS model was built applying the training data and examined using the testing data. Performance of the CNN-DS solution was compared with three previously established methods. The CNN-DS achieved a Dice coefficient score of 0.84 ± 0.06 and recall of 0.83 ± 0.07, higher than patch-wise U-Net (< 0.76). CNN-DS average running time of 0.74 ± 0.07 s was faster than PItcHPERFeCT (> 1412 s) and slice-based U-Net (> 12 s). Comparable interrater agreement rates were observed between "method-human" vs. "human-human" (Cohen's kappa coefficients > 0.82). The fully automated CNN-DS approach demonstrated expert-level accuracy in fast segmentation and quantification of hematoma, substantially improving over previous methods. Further research is warranted to test the CNN-DS solution as a software tool in clinical settings for effective stroke management.
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http://dx.doi.org/10.1038/s41598-020-76459-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652921PMC
November 2020

Neuroimaging and analytical methods for studying the pathways from mild cognitive impairment to Alzheimer's disease: protocol for a rapid systematic review.

Syst Rev 2020 04 2;9(1):71. Epub 2020 Apr 2.

Digital Health Hub, Simon Fraser University, 4190 Galleria 4, 250 - 13450 102 Ave, Surrey, BC, V3T 0A3, Canada.

Background: Alzheimer's disease (AD) is a neurodegenerative disorder commonly associated with deficits of cognition and changes in behavior. Mild cognitive impairment (MCI) is the prodromal stage of AD that is defined by slight cognitive decline. Not all with MCI progress to AD dementia. Thus, the accurate prediction of progression to Alzheimer's, particularly in the stage of MCI could potentially offer developing treatments to delay or prevent the transition process. The objective of the present study is to investigate the most recent neuroimaging procedures in the domain of prediction of transition from MCI to AD dementia for clinical applications and to systematically discuss the machine learning techniques used for the prediction of MCI conversion.

Methods: Electronic databases including PubMed, SCOPUS, and Web of Science will be searched from January 1, 2017, to the date of search commencement to provide a rapid review of the most recent studies that have investigated the prediction of conversion from MCI to Alzheimer's using neuroimaging modalities in randomized trial or observational studies. Two reviewers will screen full texts of included papers using predefined eligibility criteria. Studies will be included if addressed research on AD dementia and MCI, explained the results in a way that would be able to report the performance measures such as the accuracy, sensitivity, and specificity. Only studies addressed Alzheimer's type of dementia and its early-stage MCI using neuroimaging modalities will be included. We will exclude other forms of dementia such as vascular dementia, frontotemporal dementia, and Parkinson's disease. The risk of bias in individual studies will be appraised using an appropriate tool. If feasible, we will conduct a random effects meta-analysis. Sensitivity analyses will be conducted to explore the potential sources of heterogeneity.

Discussion: The information gathered in our study will establish the extent of the evidence underlying the prediction of conversion to AD dementia from its early stage and will provide a rigorous and updated synthesis of neuroimaging modalities allied with the data analysis techniques used to measure the brain changes during the conversion process.

Systematic Review Registration: PROSPERO,CRD42019133402.
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http://dx.doi.org/10.1186/s13643-020-01332-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7118884PMC
April 2020

Increased Intra-Subject Variability of Reaction Times and Single-Trial Event-Related Potential Components in Children With Autism Spectrum Disorder.

Autism Res 2020 02 30;13(2):221-229. Epub 2019 Sep 30.

School of Interactive Arts and Technology, Simon Fraser University, Burnaby, British Columbia, Canada.

Autism spectrum disorder (ASD) is an increasingly common neurodevelopmental disorder that affects 1 in 59 children. The cognitive profiles of individuals with ASD are varied, and the neurophysiological underpinnings of these developmental difficulties are unclear. While many studies have focused on overall group differences in the amplitude or latency of event related potential (ERP) responses, recent research suggests that increased intra-subject neural variability may also be a reliable indicator of atypical brain function in ASD. This study aimed to identify behavioral and neural variability responses during an emotional inhibitory control task in children with ASD compared to typically developing (TD) children. Children with ASD showed increased variability in response to both inhibitory and emotional stimuli, evidenced by greater reaction time variability and single-trial ERP variability of N200 and N170 amplitudes and/or latencies compared to TD children. These results suggest that the physiological basis of ASD may be more accurately explained by increased intra-subject variability, in addition to characteristic increases or decreases in the amplitude or latency of neural responses. Autism Res 2020, 13:221-229. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The cognitive functions including memory, attention, executive functions, and perception, of individuals with ASD are varied, and the physiological underpinnings of these profiles are unclear. In this study, children with ASD showed increased intra-subject neural and behavioral variability in response to an emotional inhibitory control task compared to typically developing children. These results suggest that the physiological basis of ASD may also be explained by increased behavioral and neural variability in people with ASD, rather than simply characteristic increases or decreases in averaged brain responses.
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http://dx.doi.org/10.1002/aur.2210DOI Listing
February 2020

Electrophysiology of Inhibitory Control in the Context of Emotion Processing in Children With Autism Spectrum Disorder.

Front Hum Neurosci 2019 12;13:78. Epub 2019 Mar 12.

Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada.

Autism Spectrum Disorder (ASD) is an increasingly common developmental disorder that affects 1 in 59 children. Despite this high prevalence of ASD, knowledge regarding the biological basis of its associated cognitive difficulties remains scant. In this study, we aimed to identify altered neurophysiological responses underlying inhibitory control and emotion processing difficulties in ASD, together with their associations with age and various domains of cognitive and social function. This was accomplished by assessing electroencephalographic recordings during an emotional go/nogo task alongside parent rating scales of behavior. Event related potential (ERP) N200 component amplitudes were reduced in children with ASD compared to typically developing (TD) children. No group differences were found, however, for task performance, P300 amplitude or latency, or N170 amplitude or latency, suggesting that individuals with ASD may only present conflict monitoring abnormalities, as reflected by the reduced N200 component, compared to TD individuals. Consistent with previous findings, increased age correlated with improved task performance scores and reduced N200 amplitude in the TD group, indicating that as these children develop, their neural systems become more efficient. These associations were not identified in the ASD group. Results also showed significant associations between increased N200 amplitudes and improved executive control abilities and decreased autism traits in TD children only. The newly discovered findings of decreased brain activation in children with ASD, alongside differences in correlations with age compared to TD children, provide a potential neurophysiological indicator of atypical development of inhibitory control mechanisms in these individuals.
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http://dx.doi.org/10.3389/fnhum.2019.00078DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6422887PMC
March 2019

Music and Visual Art Training Modulate Brain Activity in Older Adults.

Front Neurosci 2019 8;13:182. Epub 2019 Mar 8.

Digital Health Hub, School of Engineering Science, Simon Fraser University, Surrey, BC, Canada.

Cognitive decline is an unavoidable aspect of aging that impacts important behavioral and cognitive skills. Training programs can improve cognition, yet precise characterization of the psychological and neural underpinnings supporting different training programs is lacking. Here, we assessed the effect and maintenance (3-month follow-up) of 3-month music and visual art training programs on neuroelectric brain activity in older adults using a partially randomized intervention design. During the pre-, post-, and follow-up test sessions, participants completed a brief neuropsychological assessment. High-density EEG was measured while participants were presented with auditory oddball paradigms (piano tones, vowels) and during a visual GoNoGo task. Neither training program significantly impacted psychometric measures, compared to a non-active control group. However, participants enrolled in the music and visual art training programs showed enhancement of auditory evoked responses to piano tones that persisted for up to 3 months after training ended, suggesting robust and long-lasting neuroplastic effects. Both music and visual art training also modulated visual processing during the GoNoGo task, although these training effects were relatively short-lived and disappeared by the 3-month follow-up. Notably, participants enrolled in the visual art training showed greater changes in visual evoked response (i.e., N1 wave) amplitude distribution than those from the music or control group. Conversely, those enrolled in music showed greater response associated with inhibitory control over the right frontal scalp areas than those in the visual art group. Our findings reveal a causal relationship between art training (music and visual art) and neuroplastic changes in sensory systems, with some of the neuroplastic changes being specific to the training regimen.
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http://dx.doi.org/10.3389/fnins.2019.00182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6418041PMC
March 2019

Performance comparison of linear and non-linear feature selection methods for the analysis of large survey datasets.

PLoS One 2019 21;14(3):e0213584. Epub 2019 Mar 21.

Digital Health Hub, Simon Fraser University, Surrey, British Columbia, Canada.

Large survey databases for aging-related analysis are often examined to discover key factors that affect a dependent variable of interest. Typically, this analysis is performed with methods assuming linear dependencies between variables. Such assumptions however do not hold in many cases, wherein data are linked by way of non-linear dependencies. This in turn requires applications of analytic methods, which are more accurate in identifying potentially non-linear dependencies. Here, we objectively compared the feature selection performance of several frequently-used linear selection methods and three non-linear selection methods in the context of large survey data. These methods were assessed using both synthetic and real-world datasets, wherein relationships between the features and dependent variables were known in advance. In contrast to linear methods, we found that the non-linear methods offered better overall feature selection performance than linear methods in all usage conditions. Moreover, the performance of the non-linear methods was more stable, being unaffected by the inclusion or exclusion of variables from the datasets. These properties make non-linear feature selection methods a potentially preferable tool for both hypothesis-driven and exploratory analyses for aging-related datasets.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0213584PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6428288PMC
December 2019

Selective modulation of brain network dynamics by seizure therapy in treatment-resistant depression.

Neuroimage Clin 2018 17;20:1176-1190. Epub 2018 Oct 17.

Centre for Addiction and Mental Health, 1001 Queen St. W, Toronto, ON M6J 1A8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, 8th floor, Toronto, ON M5T 1R8, Canada; Institute of Medical Science, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; School of Mechatronic Systems Engineering, Simon Fraser University, 250-13450 102 avenue, Surrey, BC V3T 0A3, Canada. Electronic address:

Background: Electroconvulsive therapy (ECT) is highly effective for treatment-resistant depression, yet its mechanism of action is still unclear. Understanding the mechanism of action of ECT can advance the optimization of magnetic seizure therapy (MST) towards higher efficacy and less cognitive impairment. Given the neuroimaging evidence for disrupted resting-state network dynamics in depression, we investigated whether seizure therapy (ECT and MST) selectively modifies brain network dynamics for therapeutic efficacy.

Methods: EEG microstate analysis was used to evaluate resting-state network dynamics in patients at baseline and following seizure therapy, and in healthy controls. Microstate analysis defined four classes of brain states (labelled A, B, C, D). Source localization identified the brain regions associated with these states.

Results: An increase in duration and decrease in frequency of microstates was specific to responders of seizure therapy. Significant changes in the dynamics of States A, C and D were observed and predicted seizure therapy outcome (specifically ECT). Relative change in the duration of States C and D was shown to be a strong predictor of ECT response. Source localization partly associated C and D to the salience and frontoparietal networks, argued to be impaired in depression. An increase in duration and decrease in frequency of microstates was also observed following MST, however it was not specific to responders.

Conclusion: This study presents the first evidence for the modulation of global brain network dynamics by seizure therapy. Successful seizure therapy was shown to selectively modulate network dynamics for therapeutic efficacy.
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http://dx.doi.org/10.1016/j.nicl.2018.10.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6214861PMC
February 2019

Different neural activities support auditory working memory in musicians and bilinguals.

Ann N Y Acad Sci 2018 May 17. Epub 2018 May 17.

Rotman Research Institute, Baycrest Centre, University of Toronto, Toronto, Ontario, Canada.

Musical training and bilingualism benefit executive functioning and working memory (WM)-however, the brain networks supporting this advantage are not well specified. Here, we used functional magnetic resonance imaging and the n-back task to assess WM for spatial (sound location) and nonspatial (sound category) auditory information in musician monolingual (musicians), nonmusician bilinguals (bilinguals), and nonmusician monolinguals (controls). Musicians outperformed bilinguals and controls on the nonspatial WM task. Overall, spatial and nonspatial WM were associated with greater activity in dorsal and ventral brain regions, respectively. Increasing WM load yielded similar recruitment of the anterior-posterior attention network in all three groups. In both tasks and both levels of difficulty, musicians showed lower brain activity than controls in superior prefrontal frontal gyrus and dorsolateral prefrontal cortex (DLPFC) bilaterally, a finding that may reflect improved and more efficient use of neural resources. Bilinguals showed enhanced activity in language-related areas (i.e., left DLPFC and left supramarginal gyrus) relative to musicians and controls, which could be associated with the need to suppress interference associated with competing semantic activations from multiple languages. These findings indicate that the auditory WM advantage in musicians and bilinguals is mediated by different neural networks specific to each life experience.
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http://dx.doi.org/10.1111/nyas.13717DOI Listing
May 2018

Automation of CT-based haemorrhagic stroke assessment for improved clinical outcomes: study protocol and design.

BMJ Open 2018 04 19;8(4):e020260. Epub 2018 Apr 19.

Health Sciences and Innovation, Fraser Health Authority, Surrey, British Columbia, Canada.

Introduction: Haemorrhagic stroke is of significant healthcare concern due to its association with high mortality and lasting impact on the survivors' quality of life. Treatment decisions and clinical outcomes depend strongly on the size, spread and location of the haematoma. Non-contrast CT (NCCT) is the primary neuroimaging modality for haematoma assessment in haemorrhagic stroke diagnosis. Current procedures do not allow convenient NCCT-based haemorrhage volume calculation in clinical settings, while research-based approaches are yet to be tested for clinical utility; there is a demonstrated need for developing effective solutions. The project under review investigates the development of an automatic NCCT-based haematoma computation tool in support of accurate quantification of haematoma volumes.

Methods And Analysis: Several existing research methods for haematoma volume estimation are studied. Selected methods are tested using NCCT images of patients diagnosed with acute haemorrhagic stroke. For inter-rater and intrarater reliability evaluation, different raters will analyse haemorrhage volumes independently. The efficiency with respect to time of haematoma volume assessments will be examined to compare with the results from routine clinical evaluations and planimetry assessment that are known to be more accurate. The project will target the development of an enhanced solution by adapting existing methods and integrating machine learning algorithms. NCCT-based information of brain haemorrhage (eg, size, volume, location) and other relevant information (eg, age, sex, risk factor, comorbidities) will be used in relation to clinical outcomes with future project development. Validity and reliability of the solution will be examined for potential clinical utility.

Ethics And Dissemination: The project including procedures for deidentification of NCCT data has been ethically approved. The study involves secondary use of existing data and does not require new consent of participation. The team consists of clinical neuroimaging scientists, computing scientists and clinical professionals in neurology and neuroradiology and includes patient representatives. Research outputs will be disseminated following knowledge translation plans towards improving stroke patient care. Significant findings will be published in scientific journals. Anticipated deliverables include computer solutions for improved clinical assessment of haematoma using NCCT.
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http://dx.doi.org/10.1136/bmjopen-2017-020260DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5914893PMC
April 2018

Do Lifestyle Activities Protect Against Cognitive Decline in Aging? A Review.

Front Aging Neurosci 2017 20;9:381. Epub 2017 Nov 20.

Digital Health Hub, Simon Fraser University, Surrey, BC, Canada.

The number of patients suffering from dementia is expected to more than triple by the year 2040, and this represents a major challenge to publicly-funded healthcare systems throughout the world. One of the most effective prevention mechanisms against dementia lies in increasing brain- and cognitive-reserve capacity, which has been found to reduce the behavioral severity of dementia symptoms as neurological degeneration progresses. To date though, most of the factors known to enhance this reserve stem from largely immutable history factors, such as level of education and occupational attainment. Here, we review the potential for basic lifestyle activities, including physical exercise, meditation and musical experience, to contribute to reserve capacity and thus reduce the incidence of dementia in older adults. Relative to other therapies, these activities are low cost, are easily scalable and can be brought to market quickly and easily. Overall, although preliminary evidence is promising at the level of randomized control trials, the state of research on this topic remains underdeveloped. As a result, several important questions remain unanswered, including the amount of training required to receive any cognitive benefit from these activities and the extent to which this benefit continues following cessation. Future research directions are discussed for each lifestyle activity, as well as the potential for these and other lifestyle activities to serve as both a prophylactic and a therapeutic treatment for dementia.
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http://dx.doi.org/10.3389/fnagi.2017.00381DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5701915PMC
November 2017

Adaptive response criteria in road hazard detection among older drivers.

Traffic Inj Prev 2018 02 27;19(2):141-146. Epub 2017 Nov 27.

c Center for Injury Research and Policy , The Research Institute at Nationwide Children's Hospital , Columbus , Ohio.

Objectives: The majority of existing investigations on attention, aging, and driving have focused on the negative impacts of age-related declines in attention on hazard detection and driver performance. However, driving skills and behavioral compensation may accommodate for the negative effects that age-related attentional decline places on driving performance. In this study, we examined an important question that had been largely neglected in the literature linking attention, aging, and driving: can top-down factors such as behavioral compensation, specifically adaptive response criteria, accommodate the negative impacts from age-related attention declines on hazard detection during driving?

Methods: In the experiment, we used the Drive Aware Task, a task combining the driving context with well-controlled laboratory procedures measuring attention. We compared younger (n = 16, age 21-30) and older (n = 21, age 65-79) drivers on their attentional processing of hazards in driving scenes, indexed by percentage of correct responses and reaction time of hazard detection, as well as sensitivity and response criteria using signal detection analysis.

Results: Older drivers, in general, were less accurate and slower on the task than younger drivers. However, results from this experiment revealed that older, but not younger, drivers adapted their response criteria when the traffic condition changed in the driving scenes. When there was more traffic in the driving scene, older drivers became more liberal in their responses, meaning that they were more likely to report that a driving hazard was detected.

Conclusions: Older drivers adopt compensatory strategies for hazard detection during driving. Our findings showed that, in the driving context, even at an older age our attentional functions are still adaptive according to environmental conditions. This leads to considerations on potential training methods to promote adaptive strategies that may help older drivers maintain performance in road hazard detection.
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http://dx.doi.org/10.1080/15389588.2017.1373190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5921861PMC
February 2018

Differential age-related changes in localizing a target among distractors across an extended visual field.

Eur J Ageing 2017 Jun 11;14(2):167-177. Epub 2016 Oct 11.

Department of Psychology, North Carolina State University, 2310 Stinson Drive, Raleigh, NC 27695-7650 USA.

Age differences in the spatial distribution of attention over a wide field of view have only been described in terms of the spatial extent, leaving the topographical aspect unexplored. This study examined age differences between younger and older adults in good general health in an important topographical characteristic, the asymmetry between the upper and lower visual fields. In Experiment 1, we found age differences across the entire attentional visual field. In addition, age differences were greater in the upper compared to the lower field. In Experiment 2, we examined whether the finding of a greater age difference in the ability to localize a target among distractors in the upper visual field in Experiment 1 was a result of possible differential age differences between the upper and lower visual fields in the ability to localize a target even when there was no distractor competing for attention. Our results suggested that the age differences we observed were linked to age differences in the ability to filter out distractors that compete with the target for attention rather than the ability to process only the target over a wide field of view. While younger adults demonstrated an upper visual field advantage in the ability to localize a target among distractors, there was no such field advantage in older adults. We discuss this finding of diminished upper visual field advantage in older adults in light of an account of pervasive loss of neural specialization with age. We postulate that one possible explanation of age differences in the asymmetry between the upper and lower visual fields may be an adaptation to age-related physical decline. We also discuss important implications of our findings in risks of falls and vehicle crashes.
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http://dx.doi.org/10.1007/s10433-016-0399-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5550660PMC
June 2017

Brain temporal complexity in explaining the therapeutic and cognitive effects of seizure therapy.

Brain 2017 Apr;140(4):1011-1025

Temerty Centre for Therapeutic Brain Intervention, Campbell Family Research Institute, Centre for Addiction and Mental Health, ON, M6J 1H4, Canada.

Over 350 million people worldwide suffer from depression, a third of whom are medication-resistant. Seizure therapy remains the most effective treatment in depression, even when many treatments fail. The utility of seizure therapy is limited due to its cognitive side effects and stigma. The biological targets of seizure therapy remain unknown, hindering design of new treatments with comparable efficacy. Seizures impact the brains temporal dynamicity observed through electroencephalography. This dynamicity reflects richness of information processing across distributed brain networks subserving affective and cognitive processes. We investigated the hypothesis that seizure therapy impacts mood (depressive symptoms) and cognition by modulating brain temporal dynamicity. We obtained resting-state electroencephalography from 34 patients (age = 46.0 ± 14.0, 21 females) receiving two types of seizure treatments-electroconvulsive therapy or magnetic seizure therapy. We used multi-scale entropy to quantify the complexity of the brain's temporal dynamics before and after seizure therapy. We discovered that reduction of complexity in fine timescales underlined successful therapeutic response to both seizure treatments. Greater reduction in complexity of fine timescales in parieto-occipital and central brain regions was significantly linked with greater improvement in depressive symptoms. Greater increase in complexity of coarse timescales was associated with greater decline in cognition including the autobiographical memory. These findings were region and timescale specific. That is, change in complexity in occipital regions (e.g. O2 electrode or right occipital pole) at fine timescales was only associated with change in depressive symptoms, and not change in cognition, and change in complexity in parieto-central regions (e.g. Pz electrode or intra and transparietal sulcus) at coarser timescale was only associated with change in cognition, and not depressive symptoms. Finally, region and timescale specific changes in complexity classified both antidepressant and cognitive response to seizure therapy with good (80%) and excellent (95%) accuracy, respectively. In this study, we discovered a novel biological target of seizure therapy: complexity of the brain resting state dynamics. Region and timescale dependent changes in complexity of the brain resting state dynamics is a novel mechanistic marker of response to seizure therapy that explains both the antidepressant response and cognitive changes associated with this treatment. This marker has tremendous potential to guide design of the new generation of antidepressant treatments.
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http://dx.doi.org/10.1093/brain/awx030DOI Listing
April 2017

Assessing Music Perception in Young Children: Evidence for and Psychometric Features of the M-Factor.

Front Neurosci 2017 24;11:18. Epub 2017 Jan 24.

Department of Psychiatry and Medical Psychology, Federal University of Sao Paulo São Paulo, Brazil.

Given the relationship between language acquisition and music processing, musical perception (MP) skills have been proposed as a tool for early diagnosis of speech and language difficulties; therefore, a psychometric instrument is needed to assess music perception in children under 10 years of age, a crucial period in neurodevelopment. We created a set of 80 musical stimuli encompassing seven domains of music perception to inform perception of tonal, atonal, and modal stimuli, in a random sample of 1006 children, 6-13 years of age, equally distributed from first to fifth grades, from 14 schools (38% private schools) in So Paulo State. The underlying model was tested using confirmatory factor analysis. A model encompassing seven orthogonal specific domains (contour, loudness, scale, timbre, duration, pitch, and meter) and one general music perception factor, the "m-factor," showed excellent fit indices. The m-factor, previously hypothesized in the literature but never formally tested, explains 93% of the reliable variance in measurement, while only 3.9% of the reliable variance could be attributed to the multidimensionality caused by the specific domains. The 80 items showed no differential item functioning based on sex, age, or enrolment in public vs. private school, demonstrating the important psychometric feature of invariance. Like Charles Spearman's g-factor of intelligence, the m-factor is robust and reliable. It provides a convenient measure of auditory stimulus apprehension that does not rely on verbal information, offering a new opportunity to probe biological and psychological relationships with music perception phenomena and the etiologies of speech and language disorders.
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http://dx.doi.org/10.3389/fnins.2017.00018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5258735PMC
January 2017

Attentional and affective consequences of technology supported mindfulness training: a randomised, active control, efficacy trial.

BMC Psychol 2016 Nov 29;4(1):60. Epub 2016 Nov 29.

Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Rd., Mississauga, ON, L5L 1C6, Canada.

Background: Mindfulness training (MT) programs represent an approach to attention training with well-validated mental health benefits. However, research supporting MT efficacy is based predominantly on weekly-meeting, facilitator-led, group-intervention formats. It is unknown whether participants might benefit from neurofeedback-assisted, technology-supported MT (N-tsMT), in which meditation is delivered individually, without the need for a facilitator, travel to a training site, or the presence of a supportive group environment. Mirroring the validation of group MT interventions, the first step in addressing this question requires identifying whether N-tsMT promotes measurable benefits. Here, we report on an initial investigation of a commercial N-tsMT system.

Methods: In a randomized, active control trial, community-dwelling healthy adult participants carried out 6 weeks of daily practice, receiving either N-tsMT (n = 13), or a control condition of daily online math training (n = 13). Training effects were assessed on target measures of attention and well-being. Participants also completed daily post-training surveys assessing effects on mood, body awareness, calm, effort, and stress.

Results: Analysis revealed training effects specific to N-tsMT, with attentional improvements in overall reaction time on a Stroop task, and well-being improvements via reduced somatic symptoms on the Brief Symptom Inventory. Attention and well-being improvements were correlated, and effects were greatest for the most neurotic participants. However, secondary, exploratory measures of attention and well-being did not show training-specific effects. N-tsMT was associated with greater body awareness and calm, and initially greater effort that later converged with effort in the control condition.

Conclusions: Preliminary findings indicate that N-tsMT promotes modest benefits for attention and subjective well-being in a healthy community sample relative to an active control condition. However, the findings would benefit from replication in a larger sample, and more intensive practice or more comprehensive MT instruction might be required to promote the broader benefits typically reported in group format, facilitated MT.

Trial Registration: Current Controlled Trials ISRCTN43629398 . Retrospectively registered on June 16, 2016.
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http://dx.doi.org/10.1186/s40359-016-0168-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5127005PMC
November 2016

Musicianship and Tone Language Experience Are Associated with Differential Changes in Brain Signal Variability.

J Cogn Neurosci 2016 Dec 30;28(12):2044-2058. Epub 2016 Aug 30.

Baycrest Centre for Geriatric Care, Toronto, ON, Canada.

Musicianship has been associated with auditory processing benefits. It is unclear, however, whether pitch processing experience in nonmusical contexts, namely, speaking a tone language, has comparable associations with auditory processing. Studies comparing the auditory processing of musicians and tone language speakers have shown varying degrees of between-group similarity with regard to perceptual processing benefits and, particularly, nonlinguistic pitch processing. To test whether the auditory abilities honed by musicianship or speaking a tone language differentially impact the neural networks supporting nonlinguistic pitch processing (relative to timbral processing), we employed a novel application of brain signal variability (BSV) analysis. BSV is a metric of information processing capacity and holds great potential for understanding the neural underpinnings of experience-dependent plasticity. Here, we measured BSV in electroencephalograms of musicians, tone language-speaking nonmusicians, and English-speaking nonmusicians (controls) during passive listening of music and speech sound contrasts. Although musicians showed greater BSV across the board, each group showed a unique spatiotemporal distribution in neural network engagement: Controls had greater BSV for speech than music; tone language-speaking nonmusicians showed the opposite effect; musicians showed similar BSV for both domains. Collectively, results suggest that musical and tone language pitch experience differentially affect auditory processing capacity within the cerebral cortex. However, information processing capacity is graded: More experience with pitch is associated with greater BSV when processing this cue. Higher BSV in musicians may suggest increased information integration within the brain networks subserving speech and music, which may be related to their well-documented advantages on a wide variety of speech-related tasks.
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http://dx.doi.org/10.1162/jocn_a_01021DOI Listing
December 2016

Short-term Music Training Enhances Complex, Distributed Neural Communication during Music and Linguistic Tasks.

J Cogn Neurosci 2016 Oct 31;28(10):1603-12. Epub 2016 May 31.

Rotman Research Institute, Toronto, Canada.

Musical training is frequently associated with benefits to linguistic abilities, and recent focus has been placed on possible benefits of bilingualism to lifelong executive functions; however, the neural mechanisms for such effects are unclear. The aim of this study was to gain better understanding of the whole-brain functional effects of music and second-language training that could support such previously observed cognitive transfer effects. We conducted a 28-day longitudinal study of monolingual English-speaking 4- to 6-year-old children randomly selected to receive daily music or French language training, excluding weekends. Children completed passive EEG music note and French vowel auditory oddball detection tasks before and after training. Brain signal complexity was measured on source waveforms at multiple temporal scales as an index of neural information processing and network communication load. Comparing pretraining with posttraining, musical training was associated with increased EEG complexity at coarse temporal scales during the music and French vowel tasks in widely distributed cortical regions. Conversely, very minimal decreases in complexity at fine scales and trends toward coarse-scale increases were displayed after French training during the tasks. Spectral analysis failed to distinguish between training types and found overall theta (3.5-7.5 Hz) power increases after all training forms, with spatially fewer decreases in power at higher frequencies (>10 Hz). These findings demonstrate that musical training increased diversity of brain network states to support domain-specific music skill acquisition and music-to-language transfer effects.
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http://dx.doi.org/10.1162/jocn_a_00988DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5023326PMC
October 2016

Behavioral and Electrophysiological Differences in Executive Control Between Monolingual and Bilingual Children.

Child Dev 2016 07 2;87(4):1277-90. Epub 2016 May 2.

York University.

This study examined executive control in sixty-two 5-year-old children who were monolingual or bilingual using behavioral and event-related potentials (ERPs) measures. All children performed equivalently on simple response inhibition (gift delay), but bilingual children outperformed monolinguals on interference suppression and complex response inhibition (go/no-go task). On the go/no-go task, ERPs showed larger P3 amplitudes and shorter N2 and P3 latencies for bilingual children than for monolinguals. These latency and amplitude data were associated with better behavioral performance and better discrimination between stimuli for bilingual children but not for monolingual children. These results clarify the conditions that lead to advantages for bilingual children in executive control and provide the first evidence linking those performance differences to electrophysiological brain differences in children.
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http://dx.doi.org/10.1111/cdev.12538DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939124PMC
July 2016

Life-long music practice and executive control in older adults: An event-related potential study.

Brain Res 2016 07 25;1642:146-153. Epub 2016 Mar 25.

Rotman Research Institute, Baycrest Centre for Geriatric Care, University of Toronto, Canada.

Recent research has indicated that music practice can influence cognitive processing across the lifespan. Although extensive musical experience may have a mitigating effect on cognitive decline in older adults, the nature of changes to brain functions underlying performance benefits remains underexplored. The present study was designed to investigate the underlying neural mechanisms that may support apparent beneficial effects of life-long musical practice on cognition. We recorded event-related potentials (ERPs) in older musicians (N=17; average age=69.2) and non-musicians (N=17; average age=69.9), matched for age and education, while they completed an executive control task (visual go/no-go). Whereas both groups showed similar response speed and accuracy on go trials, older musicians showed fewer no-go errors. ERP recordings revealed the typical N2/P3 complex, but the nature of these responses differed between groups in that (1) older musicians showed larger N2 and P3 effects ('no-go minus go' amplitude), with the N2 amplitude being correlated with behavioral accuracy for no-go trials and (2) the topography of the P3 response was more anterior in musicians. Moreover, P3 amplitude was correlated with measures of musical experience in musicians. In our discussion of these results, we propose that music practice may have conferred an executive control advantage for musicians in later life.
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http://dx.doi.org/10.1016/j.brainres.2016.03.028DOI Listing
July 2016

Effects of short-term music and second-language training on executive control.

J Exp Child Psychol 2016 Apr 19;144:84-97. Epub 2015 Dec 19.

York University, Toronto, Ontario M3J 1P3, Canada; Rotman Research Institute, Baycrest, Toronto, Ontario M6A 2E1, Canada. Electronic address:

Separate lines of research have identified enhanced performance on nonverbal executive control (EC) tasks for bilinguals and those with music training, but little is known about the relation between them in terms of the specificity of the effects of each experience or the degree of exposure necessary to induce these changes. Using an intervention design, the current study pseudorandomly assigned 57 4- to 6-year-old children (matched on age, maternal education, and cognitive scores) to a 20-day training program offering instruction in either music or conversational French. The test battery consisted of verbal and nonverbal tasks requiring EC. All children improved on these tasks following training with some training-specific differences. No changes were observed on background or working memory measures after either training, ruling out simple practice effects. Children in both groups had better scores on the most challenging condition of a grammaticality sentence judgment task in which it was necessary to ignore conflict introduced through misleading semantic content. Children in both training groups also showed better accuracy on the easier condition of a nonverbal visual search task at post-test, but children in the French training group also showed significant improvement on the more challenging condition of this task. These results are discussed in terms of emergent EC benefits of language and music training.
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http://dx.doi.org/10.1016/j.jecp.2015.11.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4724315PMC
April 2016

'My Virtual Dream': Collective Neurofeedback in an Immersive Art Environment.

PLoS One 2015 8;10(7):e0130129. Epub 2015 Jul 8.

Rotman Research Institute, Baycrest Centre, Toronto, Ontario, Canada; Department of Psychology, University of Toronto, Ontario, Canada.

While human brains are specialized for complex and variable real world tasks, most neuroscience studies reduce environmental complexity, which limits the range of behaviours that can be explored. Motivated to overcome this limitation, we conducted a large-scale experiment with electroencephalography (EEG) based brain-computer interface (BCI) technology as part of an immersive multi-media science-art installation. Data from 523 participants were collected in a single night. The exploratory experiment was designed as a collective computer game where players manipulated mental states of relaxation and concentration with neurofeedback targeting modulation of relative spectral power in alpha and beta frequency ranges. Besides validating robust time-of-night effects, gender differences and distinct spectral power patterns for the two mental states, our results also show differences in neurofeedback learning outcome. The unusually large sample size allowed us to detect unprecedented speed of learning changes in the power spectrum (~ 1 min). Moreover, we found that participants' baseline brain activity predicted subsequent neurofeedback beta training, indicating state-dependent learning. Besides revealing these training effects, which are relevant for BCI applications, our results validate a novel platform engaging art and science and fostering the understanding of brains under natural conditions.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0130129PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4496007PMC
April 2016

Pitch expertise is not created equal: Cross-domain effects of musicianship and tone language experience on neural and behavioural discrimination of speech and music.

Neuropsychologia 2015 May 19;71:52-63. Epub 2015 Mar 19.

Department of Psychology, University of Toronto, 100 St. George Street, Toronto, ON, Canada M5S 3G3; Rotman Research Institute, Baycrest Centre for Geriatric Care, 3560 Bathurst Street, Toronto, ON, Canada M6A 2E1.

Psychophysiological evidence supports a music-language association, such that experience in one domain can impact processing required in the other domain. We investigated the bidirectionality of this association by measuring event-related potentials (ERPs) in native English-speaking musicians, native tone language (Cantonese) nonmusicians, and native English-speaking nonmusician controls. We tested the degree to which pitch expertise stemming from musicianship or tone language experience similarly enhances the neural encoding of auditory information necessary for speech and music processing. Early cortical discriminatory processing for music and speech sounds was characterized using the mismatch negativity (MMN). Stimuli included 'large deviant' and 'small deviant' pairs of sounds that differed minimally in pitch (fundamental frequency, F0; contrastive musical tones) or timbre (first formant, F1; contrastive speech vowels). Behavioural F0 and F1 difference limen tasks probed listeners' perceptual acuity for these same acoustic features. Musicians and Cantonese speakers performed comparably in pitch discrimination; only musicians showed an additional advantage on timbre discrimination performance and an enhanced MMN responses to both music and speech. Cantonese language experience was not associated with enhancements on neural measures, despite enhanced behavioural pitch acuity. These data suggest that while both musicianship and tone language experience enhance some aspects of auditory acuity (behavioural pitch discrimination), musicianship confers farther-reaching enhancements to auditory function, tuning both pitch and timbre-related brain processes.
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http://dx.doi.org/10.1016/j.neuropsychologia.2015.03.019DOI Listing
May 2015

Music training and inhibitory control: a multidimensional model.

Ann N Y Acad Sci 2015 Mar;1337:147-52

Department of Psychology, University of Toronto, Toronto, Ontario, Canada; Rotman Research Institute, Toronto, Ontario, Canada.

Training programs aimed to improve cognitive skills have either yielded mixed results or remain to be validated. The limited benefits of such regimens are largely attributable to weak understanding of (1) how (and which) interventions provide the most cognitive improvements; and (2) how brain networks and neural mechanisms that underlie specific cognitive abilities can be modified selectively. Studies indicate that music training leads to robust and long-lasting benefits to behavior. Importantly, behavioral advantages conferred by music extend beyond perceptual abilities to even nonauditory functions, such as inhibitory control (IC) and its neural correlates. Alternative forms of arts engagement or brain training do not appear to yield such enhancements, which suggests that music uniquely taps into brain networks subserving a variety of auditory as well as domain-general mechanisms such as IC. To account for such widespread benefits of music training, we propose a framework of transfer effects characterized by three dimensions: level of processing, nature of the transfer, and involvement of executive functions. We suggest that transfer of skills is mediated through modulation of general cognitive processes, in particular IC. We believe that this model offers a viable framework to test the extent and limitations of music-related changes.
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http://dx.doi.org/10.1111/nyas.12674DOI Listing
March 2015

New framework for rehabilitation - fusion of cognitive and physical rehabilitation: the hope for dancing.

Front Psychol 2014 28;5:1478. Epub 2015 Jan 28.

Department of Biology, York University Toronto, ON, Canada ; Department of Psychology, Centre for Vision Research, York University Toronto, ON, Canada.

Neurorehabilitation programs are commonly employed with the goal to help restore functionality in patients. However, many of these therapies report only having a small impact. In response to the need for more effective and innovative approaches, rehabilitative methods that take advantage of the neuroplastic properties of the brain have been used to aid with both physical and cognitive impairments. Following this path of reasoning, there has been a particular interest in the use of physical exercise as well as musical related activities. Although such therapies demonstrate potential, they also have limitations that may affect their use, calling for further exploration. Here, we propose dance as a potential parallel to physical and music therapies. Dance may be able to aid with both physical and cognitive impairments, particularly due to it combined nature of including both physical and cognitive stimulation. Not only does it incorporate physical and motor skill related activities, but it can also engage various cognitive functions such as perception, emotion, and memory, all while done in an enriched environment. Other more practical benefits, such as promoting adherence due to being enjoyable, are also discussed, along with the current literature on the application of dance as an intervention tool, as well as future directions required to evaluate the potential of dance as an alternative therapy in neurorehabilitation.
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http://dx.doi.org/10.3389/fpsyg.2014.01478DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4309167PMC
February 2015

Early stage second-language learning improves executive control: evidence from ERP.

Brain Lang 2014 Dec 6;139:84-98. Epub 2014 Nov 6.

York University, Canada; Rotman Research Institute and University of Toronto, Canada. Electronic address:

A growing body of research has reported a bilingual advantage in performance on executive control tasks, but it is not known at what point in emerging bilingualism these advantages first appear. The present study investigated the effect of early stage second-language training on executive control. Monolingual English-speaking students were tested on a go-nogo task, sentence judgment task, and verbal fluency, before and after 6 months of Spanish instruction. The training group (n = 25) consisted of students enrolled in introductory Spanish and the control group (n = 30) consisted of students enrolled in introductory Psychology. After training, the Spanish group showed larger P3 amplitude on the go-nogo task and smaller P600 amplitude on the judgment task, indicating enhanced performance, with no changes for the control group and no differences between groups on behavioral measures. Results are discussed in terms of neural changes underlying executive control after brief second-language learning.
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http://dx.doi.org/10.1016/j.bandl.2014.10.004DOI Listing
December 2014

Short-term second language and music training induces lasting functional brain changes in early childhood.

Child Dev 2015 Mar-Apr;86(2):394-406. Epub 2014 Oct 23.

Rotman Research Institute.

Immediate and lasting effects of music or second-language training were examined in early childhood using event-related potentials. Event-related potentials were recorded for French vowels and musical notes in a passive oddball paradigm in thirty-six 4- to 6-year-old children who received either French or music training. Following training, both groups showed enhanced late discriminative negativity (LDN) in their trained condition (music group-musical notes; French group-French vowels) and reduced LDN in the untrained condition. These changes reflect improved processing of relevant (trained) sounds, and an increased capacity to suppress irrelevant (untrained) sounds. After 1 year, training-induced brain changes persisted and new hemispheric changes appeared. Such results provide evidence for the lasting benefit of early intervention in young children.
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http://dx.doi.org/10.1111/cdev.12297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4376572PMC
January 2016

Age-related changes in the subcortical-cortical encoding and categorical perception of speech.

Neurobiol Aging 2014 Nov 10;35(11):2526-2540. Epub 2014 May 10.

Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Ontario, Canada; Department of Psychology, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Sciences, University of Toronto, Ontario, Canada.

Aging is associated with declines in auditory processing including speech comprehension abilities. Here, we evaluated both brainstem and cortical speech-evoked brain responses to elucidate how aging impacts the neural transcription and transfer of speech information between functional levels of the auditory nervous system. Behaviorally, older adults showed slower, more variable speech classification performance than younger listeners, which coincided with reduced brainstem amplitude and increased, but delayed, cortical speech-evoked responses. Mild age-related hearing loss showed differential correspondence with neurophysiological responses showing negative (brainstem) and positive (cortical) correlations with brain activity. Spontaneous brain activity, that is, "neural noise," did not differ between older and younger adults. Yet, mutual information and correlations computed between brainstem and cortex revealed higher redundancy (i.e., lower interdependence) in speech information transferred along the auditory pathway implying less neural flexibility in older adults. Results are consistent with the notion that weakened speech encoding in brainstem is overcompensated by increased cortical dysinhibition in the aging brain. Findings suggest aging negatively impacts speech listening abilities by distorting the hierarchy of speech representations, reducing neural flexibility through increased neural redundancy, and ultimately impairing the acoustic-phonetic mapping necessary for robust speech understanding.
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http://dx.doi.org/10.1016/j.neurobiolaging.2014.05.006DOI Listing
November 2014

Oscillatory responses to semantic and syntactic violations.

J Cogn Neurosci 2014 Dec 4;26(12):2840-62. Epub 2014 Jun 4.

Rotman Research Institute, Toronto, Ontario, Canada.

EEG studies employing time-frequency analysis have revealed changes in theta and alpha power in a variety of language and memory tasks. Semantic and syntactic violations embedded in sentences evoke well-known ERPs, but little is known about the oscillatory responses to these violations. We investigated oscillatory responses to both kinds of violations, while monolingual and bilingual participants performed an acceptability judgment task. Both violations elicited power decreases (event-related desynchronization, ERD) in the 8-30 Hz frequency range, but with different scalp topographies. In addition, semantic anomalies elicited power increases (event-related synchronization, ERS) in the 1-5 Hz frequency band. The 1-5 Hz ERS was strongly phase-locked to stimulus onset and highly correlated with time domain averages, whereas the 8-30 Hz ERD response varied independently of these. In addition, the results showed that language expertise modulated 8-30 Hz ERD for syntactic violations as a function of the executive demands of the task. When the executive function demands were increased using a grammaticality judgment task, bilinguals but not monolinguals demonstrated reduced 8-30 Hz ERD for syntactic violations. These findings suggest a putative role of the 8-30 Hz ERD response as a marker of linguistic processing that likely represents a separate neural process from those underlying ERPs.
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http://dx.doi.org/10.1162/jocn_a_00670DOI Listing
December 2014

Coordinated plasticity in brainstem and auditory cortex contributes to enhanced categorical speech perception in musicians.

Eur J Neurosci 2014 Aug 2;40(4):2662-73. Epub 2014 Jun 2.

Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences & Disorders, University of Memphis, 807 Jefferson Ave. Memphis, TN, 38105, USA.

Musicianship is associated with neuroplastic changes in brainstem and cortical structures, as well as improved acuity for behaviorally relevant sounds including speech. However, further advance in the field depends on characterizing how neuroplastic changes in brainstem and cortical speech processing relate to one another and to speech-listening behaviors. Here, we show that subcortical and cortical neural plasticity interact to yield the linguistic advantages observed with musicianship. We compared brainstem and cortical neuroelectric responses elicited by a series of vowels that differed along a categorical speech continuum in amateur musicians and non-musicians. Musicians obtained steeper identification functions and classified speech sounds more rapidly than non-musicians. Behavioral advantages coincided with more robust and temporally coherent brainstem phase-locking to salient speech cues (voice pitch and formant information) coupled with increased amplitude in cortical-evoked responses, implying an overall enhancement in the nervous system's responsiveness to speech. Musicians' subcortical and cortical neural enhancements (but not behavioral measures) were correlated with their years of formal music training. Associations between multi-level neural responses were also stronger in musically trained listeners, and were better predictors of speech perception than in non-musicians. Results suggest that musicianship modulates speech representations at multiple tiers of the auditory pathway, and strengthens the correspondence of processing between subcortical and cortical areas to allow neural activity to carry more behaviorally relevant information. We infer that musicians have a refined hierarchy of internalized representations for auditory objects at both pre-attentive and attentive levels that supplies more faithful phonemic templates to decision mechanisms governing linguistic operations.
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http://dx.doi.org/10.1111/ejn.12627DOI Listing
August 2014

Producing bilinguals through immersion education: Development of metalinguistic awareness.

Appl Psycholinguist 2014 Jan;35(1):177-191

Rotman Research Institute of Baycrest.

This study examined metalinguistic awareness in children who were becoming bilingual in an immersion education program. The purpose was to determine at what point in emerging bilingualism the previously reported metalinguistic advantages appear and what types of metalinguistic tasks reveal these developmental differences. Participants were 124 children in second and fifth grades who were enrolled in either a French immersion or a regular English program. All children were from monolingual English-speaking homes and attended local public schools in middle socioeconomic neighborhoods. Measures included morphological awareness, syntactic awareness, and verbal fluency, with all testing in English. These tasks differed in their need for executive control, a cognitive ability that is enhanced in bilingual children. Overall, the metalinguistic advantages reported in earlier research emerged gradually, with advantages for tasks requiring more executive control (grammaticality judgment) appearing later and some tasks improving but not exceeding performance of monolinguals (verbal fluency) even by fifth grade. These findings demonstrate the gradual emergence of changes in metalinguistic concepts associated with bilingualism over a period of about 5 years. Performance on English-language proficiency tasks was maintained by French immersion children throughout in spite of schooling being conducted in French.
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http://dx.doi.org/10.1017/S0142716412000288DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3987956PMC
January 2014