Auditory Event-Related Potentials Associated With Music Perception in Cochlear Implant Users

A short review of the literature on auditory event-related potentials and mismatch negativities (MMN) in cochlear implant users engaged in music-related auditory perception tasks is presented. Behavioral studies that have measured the fundamental aspects of music perception in CI users have found that they usually experience poor perception of melody, pitch, harmony as well as timbre (Limb and Roy, 2014). This is thought to occur not only because of the technological and acoustic limitations of the device, but also because of the biological alterations that usually accompany deafness. In order to improve music perception and appreciation in individuals with cochlear implants, it is essential to better understand how they perceive music. As suggested by recent studies, several different electrophysiological paradigms can be used to reliably and objectively measure normal-hearing individuals' perception of fundamental musical features. These techniques, when used with individuals with cochlear implants, might contribute to determine how their peripheral and central auditory systems analyze musical excerpts. The investigation of these cortical activations can moreover give important information on other aspects related to music appreciation, such as pleasantness and emotional perception. The studies reviewed suggest that cochlear implantation alters most fundamental musical features, including pitch, timbre, melody perception, complex rhythm, and duration (e.g., Koelsch et al., 2004b; Timm et al., 2012, 2014; Zhang et al., 2013a,b; Limb and Roy, 2014). A better understanding of how individuals with cochlear implants perform on these tasks not only makes it possible to compare their performance to that of their normal-hearing peers, but can also lead to better clinical intervention and rehabilitation

Toward a model of multiple paths to language learning: response to commentaries

Language learning, while seemingly effortless for young learners, is a complex process involving many interacting pieces, both within the child and in their language-learning environments, which can result in unique language learning trajectories and outcomes. How does the brain adjust to or accommodate the myriad variations that occur during this developmental process. How does it adapt and change over time? In our review, we proposed that the timing, quantity, and quality of children's early language experiences, particularly during an early sensitive period for the acquisition of phonology, shape the establishment of neural phonological representations that are used to establish and support phonological working memory (PWM). The efficiency of the PWM system in turn, we argued, influences the acquisition and processing of more complex aspects of language. In brief, we proposed that experience modulates later language outcomes through its early effects on PWM. We supported this claim by reviewing research from several unique groups of language learners who experience delayed exposure to language (children with cochlear implants [CI] or internationally adopted [IA] children, and children with either impoverished [signing deaf children with hearing parents)] or enriched [bilingual] early language experiences). By comparing PWM and language outcomes in these groups, we sought to highlight general patterns in language development that emerge based on variation in early language exposure. Moving forward, we also proposed that the language acquisition patterns in these groups, and others, can be used to understand how variability in early language input might affect the neural systems supporting language development and how this might affect language learning itself

Variations in phonological working memory: linking early language experiences and language learning outcomes

In order to build complex language from perceptual input, children must have access to a powerful information processing system that can analyze, store, and use regularities in the signal to which the child is exposed. In this article, we propose that one of the most important parts of this underlying machinery is the linked set of cognitive and language processing components that comprise the child's developing working memory (WM). To examine this hypothesis, we explore how variations in the timing, quality, and quantity of language input during the earliest stages of development are related to variations in WM, especially phonological WM (PWM), and in turn language learning outcomes. In order to tease apart the relationships between early language experience, WM, and language development, we review research findings from studies of groups of language learners who clearly differ with respect to these aspects of input. Specifically, we consider the development of PWM in children with delayed exposure to language, that is, children born profoundly deaf and exposed to oral language following cochlear implantation and internationally adopted children who have delayed exposed to the adoption language; children who experience impoverished language input, that is, children who experience early bouts of otitis media and signing deaf children born to nonsigning hearing parents; and children with enriched early language input, that is, simultaneous bilinguals and second language learners

Language and verbal memory abilities of internationally adopted children from China

The purpose of the present research program was to investigate IA children's language abilities during school age in order to see whether the difficulties reported in this population at younger ages persist (e.g., Gauthier & Genesee, 2011) or if they decrease with more exposure to the adopted language. Another goal was to investigate if IA children have verbal memory difficulties in addition to their language lags. Note that these studies all compared IA children to non-adopted monolingual French-speaking children matched on age, gender, and socio-economic status.Study 1 evaluated the language abilities of IA children from China adopted into French-speaking families as well as their non-verbal cognitive abilities, their socio-emotional development, and their health status. The children were between 7-8 years of age at the time of testing. The IA children's age at the time of adoption ranged between 6-21 months. The results showed that the IA children performed significantly lower than the control children on expressive vocabulary, knowledge of word definitions, receptive grammar, and sentence recall.Study 2 was conducted to investigate IA children's mastery of object clitics during school age. The goal of this study was to determine whether, with sufficient amount of language exposure, IA children are able to master this aspect of French. The IA children were assessed using a Clitic Elicitation task. The participants in Study 2 were the same as those in Study 1. The results indicated that the IA children omitted significantly more accusative object clitics and made significantly more agreement errors in gender and/or numberusing clitics than the non-adopted children.Study 3 was undertaken in order to examine IA children's memory abilities. Children's verbal short-term memory (STM), verbal working memory (WM), verbal long-term memory (LTM), non-verbal STM, non-verbal WM, non-verbal cognitive development, socio-emotional development, and language abilities were assessed. The children were between 9-12 years of age at the time of testing and the IA children's age at the time of adoption ranged between 6 and 24 months of age. The results of this study showed that, although the groups did not differ on measures of non-verbal cognitive ability and socio-emotional development, the IA children performed significantly lower than the controls on expressive and receptive vocabulary, receptive grammar, a word association test, and on measures of verbal STM, verbal WM, and verbal LTM. The groups did not differ on non-verbal memory ability, suggesting language-specific memory difficulties. Regression analyses suggested that the IA children's language abilities were best predicted by their verbal memory abilities, verbal STM in particular, while the CTL children's performance on language measures was best predicted by their length of exposure to French. Overall, the findings suggest that, while IA children exhibit normal general development, their verbal memory abilities and aspects of their language abilities are below those of control children matched on age, gender, and SES. These difficulties suggest very early age of acquisition effects on language and verbal memory abilities, but also that the IA children's verbal memory lags might account for their lags in language, at least proximally.L'objectif du présent programme de recherche était d'évaluer, à l'âge scolaire, les habiletés langagières d'enfants adoptés internationalement (AI) afin de déterminer si les difficultés rapportées chez des enfants AI d'âge préscolaire persistent (e.g., Gauthier & Genesee, 2011) ou si elles diminuent avec plus d'exposition à la langue d'adoption. Un autre objectif était de déterminer si les enfants AI ont des difficultés de mémoire verbale en plus de leurs retards de langage. Notez que ces études ont toutes comparées les enfants AI à des enfants non-adoptés, monolingues francophones et appariés sur l'âge, le sexe et le statut socioéconomique. L'étude 1 a évalué les habiletés langagières d'enfants AI de Chine par des familles francophones, ainsi que leurs habiletés cognitives non-verbales, leur développement socio-émotionnel et leur santé. Les enfants étaient âgés de 7-8 ans au moment de l'étude. Les enfants AI étaient âgés de 6-21 mois lors de leur adoption. Les résultats ont démontré que la performance des enfants AI aux tests de vocabulaire expressif, de définition de mots, de grammaire réceptive et de répétition de phrases sont significativement plus faibles que celle des contrôles. L'étude 2 a été réalisée dans le but d'évaluer la maitrise des clitiques objets par les enfants AI d'âge scolaire. Le but de cette étude était de déterminer si, avec une exposition suffisante à leur langue d'adoption, les enfants AI sont capables de maitriser cet aspect du français. Les enfants AI ont été évalués à l'aide d'un test d'élicitation de clitiques. Les participants de l'étude 2 étaient les mêmes que ceux de l'étude 1. Les résultats ont indiqués que les enfants AI omettent significativement plus de clitiques objets et produisent significativement plus de clitiques objets contenant des erreurs en genre et/ou nombre que les enfants non-adoptés. L'étude 3 a été entreprise dans le but d'examiner la mémoire chez les enfants AI. La mémoire verbale à court-terme, la mémoire verbale de travail, la mémoire verbale à long-terme, la mémoire non-verbale à court-terme, la mémoire de travail non-verbale,le développement cognitif non-verbal, le développement socio-émotionnel et les habiletés langagières des enfants ont été évalués. Les enfants étaient âges de 9-12 ans au moment de l'étude. Les enfants AI étaient âgés de 6-24 mois au moment de leur adoption. Les résultats de cette étude ont démontré que, malgré le fait que la performance des groupes aux tests de développement cognitif non-verbal et de développement socio-émotionnel soit similaire, les enfants AI performent significativement plus faiblement que les enfants contrôles aux test de vocabulaire expressif et réceptif, de grammaire réceptive, d'association de mots ainsi qu'aux tests de mémoire verbale à court-terme, de mémoire verbale de travail et de mémoire verbale à long-terme. Les groupes ont toutefois performé de façon similaire aux tests de mémoire non-verbale à court-terme et de mémoire de travail non-verbale, suggérant des difficultés spécifiques au langage. Des analyses de régressions ont démontré que les habiletés langagières des enfants AI sont mieux prédites par leur mémoire verbale, la mémoire verbale à court-terme en particulier, alors que, pour les contrôles, le meilleur prédicteur de leur performance aux tests de langage est la durée de leur exposition au français. De façon générale, les résultats suggèrent que, bien que le développement général des enfants AI est normal, leur mémoire verbale et certains aspects de leurs habiletés langagières sont en-deçà de celles des enfants contrôles appariés pour l'âge, le sexe et le statut-socioéconomique. Ces difficultés suggèrent des effets très précoces de « l'âge d'acquisition » sur le langage et sur la mémoire verbale, mais également que les délais de mémoire verbale des enfants AI pourraient expliquer leurs retards de langage, au moins de façon proximale

The Clinical Utility of Vestibular-Evoked Myogenic Potentials in the Diagnosis of Ménière’s Disease

Ménière’s disease (MD) is a condition that has been proposed over 150 years ago, which involves audiological and vestibular manifestations, such as aural fullness, tinnitus, vertigo, and fluctuating hearing thresholds. Over the past few years, many researchers have assessed different techniques to help diagnose this pathology. Vestibular-evoked myogenic potential (VEMP) is an electrophysiological method assessing the saccule (cVEMP) and the utricule (oVEMP). Its clinical utility in the diagnosis of multiple pathologies, such as superior canal dehiscence, has made this tool a common method used in otologic clinics. The main objective of the present review is to determine the current state of knowledge of the VEMP in the identification of MD, such as the type of stimuli, the frequency tuning, and the interaural asymmetry ratio of the cVEMP and the oVEMP. Results show that the type of stimulation, the frequency sensitivity shift and the interaural asymmetry ratio (IAR) could be useful tool to diagnose and describe the evolution of MD. It is, however, important to emphasize that further studies are needed to confirm the utility of VEMP in the identification of MD in its early stage, using either bone-conduction vibration or air-conduction stimulation, which is of clinical importance when it comes to early intervention

State-of-the-art assessment allows for improved vestibular evoked myogenic potential test-retest reliability

The goal of the present study was to evaluate the test-retest reliability values of myogenic responses using the latest guidelines for vestibular assessment. Twenty-two otologically and neurologically normal adults were assessed twice, on two different days. The analyses were carried out using interclass correlations. The results showed that the latest recommendations for vestibular assessment lead to test-retest reliability values that are as high, or greater, than those reported in previous studies. The results suggest that state-of-the-art testing, using the latest recommendations as well as electromyography control, improves reliability values of myogenic responses, more specifically for the cervical vestibular evoked myogenic potentials. The impact of small differences in experimental procedures on the reliability values of myogenic responses is also addressed

Enhancement of visual biological motion recognition in early-deaf adults: Functional and behavioral correlates.

Deafness leads to brain modifications that are generally associated with a cross-modal activity of the auditory cortex, particularly for visual stimulations. In the present study, we explore the cortical processing of biological motion that conveyed either non-communicative (pantomimes) or communicative (emblems) information, in early-deaf and hearing individuals, using fMRI analyses. Behaviorally, deaf individuals showed an advantage in detecting communicative gestures relative to hearing individuals. Deaf individuals also showed significantly greater activation in the superior temporal cortex (including the planum temporale and primary auditory cortex) than hearing individuals. The activation levels in this region were correlated with deaf individuals' response times. This study provides neural and behavioral evidence that cross-modal plasticity leads to functional advantages in the processing of biological motion following lifelong auditory deprivation