Critical Period For Language Acquisition Research Articles

Imprinting and Critical Period of Language Acquisition

In language acquisition, imprinting during the critical period helps people to encode the information and influences received from outside more actively. It provides opportunity for people, especially children, to be socialized and have closer interactions with their environment, later forms social attachment. After the critical period, people still can learn new languages but requires more effort for the same outcome.

Uncovering How Musicians Develop Perfect Pitch: A Literature Review

Introduction: Absolute pitch (AP), or more commonly known as “perfect pitch”, is the rare ability to label pitches without needing a reference note. While its mechanisms are still unknown, there are many different theories regarding how and why some individuals develop AP, while others do not. Some argue that the ability is genetically inherited, while others argue that AP is a skill preferentially learned at a young age, with links to musical training and tonal language learning. This review investigates the possible factors that lead to AP development, as well as possible neurobiological underpinnings of the ability. Methods: A literature search was conducted using scientific databases to reveal studies examining the impact of genetic, learning, musical training, language, and neuroimaging on AP development. Empirical studies written in English were examined for this review, with emphasis on how AP is differentially reflected in developmental and neuroimaging perspectives. Results: Genetics, learning, musical training, and language all play a role in AP development, with some having a greater impact than others. Young children are easily taught absolute pitch using training programs, while it is much more difficult in adults. Furthermore, the apparent critical period for AP development closely resembles the time frame of the critical period of language acquisition. The phenomenon of AP is apparent through localized brain function, which differs from non-AP individuals. Discussion: Genetic, musical training, and language all play an interconnected role in the development of AP. However, neuroimaging research is vastly separate, not integrating findings from other areas. Overall, looking at the various factors combined allows for a more complete understanding of AP. Conclusion: Currently, there is a lack of research linking genetic and environmental influences on AP development with specific brain structure and function, which future neuroimaging research should seek to do. Understanding AP development benefits musicians and furthers an understanding of human perception of the auditory environment.

Compreensão de estruturas sintáticas com movimento A’ e com movimento A em crianças portuguesas surdas com implante coclear: efeitos da idade de início de exposição ao input linguístico e do tempo de exposição à língua

In the period in which language should be acquired, auditory input deprivation compromises oral language exposure. The literature reports difficulties in the oral comprehension of syntactic dependencies resulting from A’ movement, but no difficulties in the acquisition of syntactic structures with A-movement in hearing-impaired children with hearing aids. Our study investigates the effects of the total deprivation of linguistic input during the first year(s) of life (critical period of language acquisition) and length of language exposure on the comprehension of dependencies with A and A-bar movement (Wh- questions, relative clauses, and passives) in 47 Portuguese hearing-impaired children with cochlear implants. The results reveal that CI activation before age 3 combined with at least 6 years of language exposure determines comprehension of Wh- questions and relatives at the same level as the control group. The same does not happen with the comprehension of passives, that remain problematic in this population even after prolonged exposure. We discuss these findings in light of theoretical proposals that attribute the acquisition of passives to maturational constraints.

Lexical Cohesion and Corpus Construction in Primary and Secondary School English Teaching

English learning in primary and secondary schools is the critical period of language acquisition, which is very important for developing students' language ability. Among them, vocabulary teaching cohesion is the basis of English learning, which affects students' learning at different stages to a great extent. In the process of English learning, if the teaching vocabulary cohesion is not reasonable, it will not only reduce students' learning efficiency, but also affect students' ability training in listening, speaking, reading and writing skills. This paper studies the lexical cohesion in primary and secondary school English teaching and constructs the corresponding lexical corpus.

Early language intervention in deaf children of hearing parents

Language development is often hampered by the fact that 90 per cent of deaf children are born into hearing families who do not know Sign language (SL) or haven't had any previous contact with the deaf world. Such parents often use only spoken language to communicate with the child, which results in no or very little language exposure. Many deaf children only start to learn a language, signed or spoken, when they start attending school, usually between the ages of three and seven. As a result, the deaf child has a delay in cognitive and language development and finds it hard to learn a SL, like South African Sign Language (SASL), as well as a written language (e.g., English). This late exposure to SL proves to be a serious cognitive problem for deaf children when compared to those children who acquired language from birth. This problem led to the research question namely, whether deaf children’s language and cognition can still develop to the required level for school readiness if early language intervention (ELI) takes place within the critical period of language acquisition. To answer the question, a case study was done at a school for the deaf and blind with a small group of deaf learners in the foundation phase. The results show that the little language exposure these children received in only one year of school already made a huge difference to their language and cognitive development. This article also makes recommendations to the various stakeholders in deaf education.

Lifelong Bilingualism and Literacy Skills Use Among Hispanic Adults

Literacy skills use in everyday life is associated with social (e.g., civic participation) and economic (e.g., higher wages) benefits throughout the life course. Yet, the use of literacy skills may be lower among immigrants and those with limited language proficiency. No prior research examined associations between bilingualism in early life — a critical period for language acquisition — English literacy skills, and the use of literacy skills in later life of Hispanic adults. The objective of this study is to determine whether lifelong bilingualism (i.e., learning a second language in childhood and still understanding today) is associated with Hispanics’ everyday use of literacy skills later in life. Nationally representative data (n = 412) of Hispanics 35 years and older were obtained from the 2012/2014 Program for International Assessment of Adult Competencies (PIAAC). A series of logistic regression models were used to examine the associations between lifelong bilingualism and several measures of literacy skills use in everyday life. Results showed that lifelong bilingualism (vs. being monolingual) was negatively associated with the daily use of letters, notes, and e-mails (Odds Ratio = 0.426, p< 0.05), reading financial statements (Odds Ratio = 0.474, p< 0.05), and reading diagrams (Odds Ratio = 0.391, p< 0.05). Additionally, literacy was a consistent predictor of skill use. While bilingualism is generally beneficial for aging adults, our findings suggest that, among Hispanics, lifelong bilingualism is associated with the less frequent use of literacy skills later in life. We discuss the possible theoretical and practice implications of these findings.

Digital Entertainment to Support Toddlers’ Language and Cognitive Development

This current research aimed at seeing how English nursery rhymes and kids’ songs as learning media support toddlers who are not living in an English speaking country (Indonesia) but exposed to the English language media during their normal baby-sitting times to learning English. To observe how two Indonesian toddlers learned English language in their early critical period of language acquisition through co-watching activity, Early Development Instrument which focuses on language and cognitive development domain with reading awareness and reciting memory subdomain was applied to observe two subjects after 15 month treatments (from age 10-24 months). The results show that the media and the co-watching activity are able to support the toddlers’ understanding of the English words spoken and their ability to produce the intelligent pronunciation of those words. The interesting fact reveals that English which is normatively learned merely as a foreign language to most Indonesian people is no longer something far-off to the toddlers who are exposed to it through English nursery rhymes and kids’ songs online since they are at the very young age. They naturally tend to be bilingual since at the same time they learn their mother tongue.

Education and health of children with hearing loss: the necessity of signed languages.

Medical and educational interventions for children with hearing loss often adopt a single approach of spoken language acquisition through the use of technology, such as cochlear implants. These approaches generally ignore signed languages, despite no guarantees that the child will acquire fluency in a spoken language. Research with children who have a cochlear implant and do not use a signed language indicates that language outcomes are very variable and generally worse than their non-deaf peers. In contrast, signing children with cochlear implants have timely language development similar to their non-deaf peers that also exceeds their non-signing peers with cochlear implants. Natural signed languages have been shown to have the same neurocognitive benefits as natural spoken language while being fully accessible to deaf children. However, it is estimated less than 2% of the 34 million deaf children worldwide receive early childhood exposure to a signed language. Most deaf children are, therefore, at risk for language deprivation during the critical period of language acquisition in the first five years of life. Language deprivation has negative consequences for developmental domains, which rely on timely language acquisition. Beyond the adverse effects on a child’s education, language deprivation also affects deaf people’s mental and physical health and access to health care, among others. Therefore, policies in accordance with the United Nations Convention on the rights of persons with disabilities are needed. Such policies would ensure early intervention and education services include signed languages and bilingual programmes where the signed language is the language of instruction.

Auditory T-Complex Reveals Reduced Neural Activities in the Right Auditory Cortex in Musicians With Absolute Pitch.

Absolute pitch (AP) is the ability to identify the pitch names of arbitrary musical tones without being given a reference pitch. The acquisition of AP typically requires early musical training, the critical time window for which is similar to that for the acquisition of a first language. This study investigated the left–right asymmetry of the auditory cortical functions responsible for AP by focusing on the T-complex of auditory evoked potentials (AEPs), which shows morphological changes during the critical period for language acquisition. AEPs evoked by a pure-tone stimulus were recorded in high-AP musicians, low-AP musicians, and non-musicians (n = 19 each). A balanced non-cephalic electrode (BNE) reference was used to examine the left–right asymmetry of the N1a and N1c components of the T-complex. As a result, a left-dominant N1c was observed only in the high-AP musician group, indicating “AP negativity,” which has previously been described as an electrophysiological marker of AP. Notably, this hemispheric asymmetry was due to a diminution of the right N1c rather than enhancement of the left N1c. A left-dominant N1a was found in both musician groups, irrespective of AP. N1c and N1a exhibited no left–right asymmetry in non-musicians. Hence, music training and the acquisition of AP are both accompanied by a left-dominant hemispheric specialization of auditory cortical functions, as indexed by N1a and N1c, respectively, but the N1c asymmetry in AP possessors was due to reduced neural activities in the right hemisphere. The use of a BNE is recommended for evaluating these radially oriented components of the T-complex.

Critical appraisal of appropriate method for early detection of hearing impairment in newborns in a tertiary care centre

Background: Hearing plays a vital role in developmental of a child. Hearing loss not only affects the speech and language development of a child but also affects the social, emotional and intellectual development. Hearing is important in the first 2 years of life as this is the critical period for language acquisition. Thereby early detection and intervention for hearing loss is recommended. However, there are no standard protocols for newborn hearing screening. Hence, this study is undertaken to evaluate the appropriate protocol for early detection of hearing impairment in newborns and to ascertain the sensitivity and specificity of Distortion Product Oto-acoustic Emission (DPOAE) and Auditory Brainstem Response (ABR).Methods: A prospective study was conducted in the Department of Paediatrics and Department of Audiology and Speech Pathology in SRM Medical College Hospital and Research Centre. A total of 122 neonates were screened for hearing loss using both DPOAE and ABR before discharge from the hospital. A rescreening with ABR after 1 month was done for those infants who had hearing loss at the initial screening.Results: The study revealed that 16.4% of infants had hearing loss. The referral rate of DPOAE was 54.1% and ABR was 16.4%. ABR had higher passing rates when compared to DPOAE. In a combined screening with both DPOAE and ABR, 17 (13.9%) babies had failed DPOAE with abnormal hearing in ABR (True positives), 49 (40.2%) babies failed DPOAE but had normal hearing in ABR (False positives), 3 (2.5%) babies passed DPOAE but had hearing loss in ABR (False negatives) and 53 (43.4%) babies passed DPOAE and had normal hearing in ABR (True negatives). The association between the results of DPOAE and ABR was statistically significant (0.002). Auditory neuropathy was detected in 3 out of 122 neonates. All these 3 babies belonged to high-risk population. The prevalence of auditory neuropathy is 2.5% which is much lower when compared to other studies. The sensitivity and specificity of DPOAE is 85% and 51.9% respectively. The sensitivity and specificity of ABR was 100%.Conclusions: Present study concludes that the use of combination protocol using both DPOAE and ABR identifies babies with auditory neuropathy spectrum disorder and also ensures high sensitivity and acceptable specificity. Thus, helps in early identification and intervention of congenital hearing loss.

Amplitude Modulation Detection in Children with a History of Temporary Conductive Hearing Loss Remains Impaired for Years After Restoration of Normal Hearing

Otitis media with effusion (OME) is considered a form of relative sensory deprivation that often occurs during a critical period of language acquisition in children. Animal studies have demonstrated that hearing loss during early development can impair behavioral sensitivity to amplitude modulation (AM), critical for speech understanding, even after restoration of normal hearing thresholds. AM detection in humans with a history of OME-associated conductive hearing loss (CHL) has not been previously investigated. Our objective was to determine whether OME-associated CHL in children ages 6months to 3years results in deficits in AM detection in later childhood, after restoration of normal audiometric thresholds. Children ages 4 to 7years with and without a history of OME-associated CHL participated in an AM detection two-alternative forced-choice task at 8 and 64Hz modulation frequencies using a noise carrier signal and an interactive touch screen interface. Thirty-four subjects were studied (17 with a history of OME-related CHL and 17 without). Modulation detection thresholds improved with age and were slightly lower (more sensitive) for the 64Hz modulation frequency for both groups. Modulation detection thresholds of children with a history of OME-associated CHL were higher than control thresholds at 5years, but corrected to expected levels between ages 6-7. OME-associated CHL results in impaired AM detection, even when measured years after restoration of normal audiometric thresholds. Future studies may shed light on implications for speech and language development and academic success for children affected by OME and associated conductive hearing loss.

A critical period for second language acquisition: Evidence from 2/3 million English speakers

Children learn language more easily than adults, though when and why this ability declines have been obscure for both empirical reasons (underpowered studies) and conceptual reasons (measuring the ultimate attainment of learners who started at different ages cannot by itself reveal changes in underlying learning ability). We address both limitations with a dataset of unprecedented size (669,498 native and non-native English speakers) and a computational model that estimates the trajectory of underlying learning ability by disentangling current age, age at first exposure, and years of experience. This allows us to provide the first direct estimate of how grammar-learning ability changes with age, finding that it is preserved almost to the crux of adulthood (17.4 years old) and then declines steadily. This finding held not only for “difficult” syntactic phenomena but also for “easy” syntactic phenomena that are normally mastered early in acquisition. The results support the existence of a sharply-defined critical period for language acquisition, but the age of offset is much later than previously speculated. The size of the dataset also provides novel insight into several other outstanding questions in language acquisition.

JOURNAL OF PEDIATRIC CRITICAL CARE

The Landau-Kleffner syndrome or the syndrome of acquired epileptic aphasia was first described in 1957. The disorder is characterized by gradual or rapid loss of language in a previously normal child. Acquired epileptic aphasia (AEA) typically develops in healthy children who acutely or progressively lose receptive and expressive language ability coincident with the appearance of paroxysmal electroencephalographs (EEG) changes. In most cases described in detail, a clearly normal period of motor and language development occurs before acquired epileptic aphasia symptoms appear. Because this syndrome appears during such a critical period of language acquisition in a child’s life, speech production may be affected just as severely as language comprehension. The onset of LKS is typically between 18 months and 13 years. The prevalence of clinical seizures in acquired epileptic aphasia (LKS) is 70-85%. The syndrome can be difficult to diagnose and may be misdiagnosed as autism, pervasive developmental disorder, hearing impairment, learning disability, auditory/ verbal processing disorder, attention deficit disorder, intellectual disability, childhood schizophrenia, or emotional/behavioural problems. An EEG (electroencephalogram) test is imperative to a diagnosis.

Language Acquisition in Late Critical Period: A Case Report

Studies carried out to support the existence of a critical period for language acquisition have concentrated mainly on the case of being in total deprivation from language contact, and in particular deprivation from auditory input in the entire time span before puberty. While arguing for a useful distinction between early and late critical periods, we attempt to investigate the written language production of a profoundly deaf young woman, here referred to as Maryam, who has missed the early years, before her official education as a deaf person began at the age of 54 months. During the study, several texts that we asked her to write were analysed. In addition, we held a test in which she was required to set disordered sentences in the right order. The results of text analysis indicated that despite her ability to communicate through written Persian, a considerable number of syntactically and morphologically ill-formed structures were observed in the texts she produced. While confirming the idea that some aspects of language, such as syntax and morphology, are affected much more than semantics and vocabulary, the existence of these deficits seems to strengthen the importance of early years in acquiring a language.

The Comprehension and Production of Wh-Questions in Deaf and Hard-of-Hearing Children

Hearing loss during the critical period for language acquisition restricts spoken language input. This input limitation, in turn, may hamper syntactic development. This study examined the comprehension, production, and repetition of Wh-questions in deaf or hard-of-hearing (DHH) children. The participants were 11 orally trained Hebrew-speaking children aged 9.1-12.4 with moderate-to-profound hearing loss from birth, who consistently used hearing aids or cochlear implants and who had difficulties understanding relative clauses. Experiment 1 tested the comprehension of Wh-questions using a picture selection task, comparing subject with object questions and who- with which-questions; Experiment 2 tested the production of subject and object who-questions using an elicitation task; and Experiment 3 tested the repetition of Wh-questions and other structures derived by Wh-movement. All the DHH participants showed difficulty in the comprehension, production, and repetition of object questions, and their performance was significantly below that of hearing children. In contrast, they repeated embedded sentences without movement well, indicating that their deficit is in syntactic movement rather than embedding or the CP node in the syntactic tree. The results provide additional evidence that DHH children have difficulties with Wh-movement and emphasize that Wh-questions, which are crucial for communication, can be severely impaired in these children.

Age of Onset and Nativelikeness in a Second Language: Listener Perception Versus Linguistic Scrutiny

The incidence of nativelikeness in adult second language acquisition is a controversial issue in SLA research. Although some researchers claim that any learner, regardless of age of acquisition, can attain nativelike levels of second language (L2) proficiency, others hold that attainment of nativelike proficiency is, in principle, impossible. The discussion has traditionally been framed within the paradigm of a critical period for language acquisition and guided by the question of whether SLA is constrained by the maturation of the brain. The work presented in this article can be positioned among those studies that have focused exclusively on the apparent counterexamples to the critical period. We report on a large‐scale study of Spanish/Swedish bilinguals (n = 195) with differing ages of onset of acquisition (&lt;1–47 years), all of whom identify themselves as potentially nativelike in their L2. Listening sessions with native‐speaker judges showed that only a small minority of those bilinguals who had started their L2 acquisition after age 12, but a majority of those with an age of onset below this age, were actually perceived as native speakers of Swedish. However, when a subset (n = 41) of those participants who did pass for native speakers was scrutinized in linguistic detail with a battery of 10 highly complex, cognitively demanding tasks and detailed measurements of linguistic performance, representation, and processing, none of the late learners performed within the native‐speaker range; in fact, the results revealed also that only a few of the early learners exhibited actual nativelike competence and behavior on all measures of L2 proficiency that were employed. Our primary interpretation of the results is that nativelike ultimate attainment of a second language is, in principle, never attained by adult learners and, furthermore, is much less common among child learners than has previously been assumed.

Beyond the critical period: Processing-based explanations for poor grammaticality judgment performance by late second language learners

This research explores if poor grammaticality judgments of late (age of arrival ⩾ 12) second language learners often attributed to being beyond the critical period for language acquisition can be better explained by processing difficulties due to (1) low L2 working memory capacity, (2) poor L2 decoding, and/or (3) inadequate L2 processing speed. In Experiment 1, late L2 learners and native speakers performed measures of English working memory, decoding, and speed, and a grammaticality judgment task. Compared to native speakers, late L2 learners were poorer on all measures. L2 span, L2 decoding ability, and arrival age correlated with L2 judgment accuracy. Late L2 learners had less difficult judging some structures (e.g., word order, questions) than others (e.g., articles, regular past). To simulate these deficits, Experiment 2 placed native speakers under stressors relevant to memory (low or high digit load), decoding (noise), or speed (response deadline, compressed speech) during grammaticality judgment. Span and decoding scores correlated with judgment under relevant stressors. The stressors caused native speakers to show selective deficits in judgment, with some structures (e.g., word order) being less vulnerable to stress than others (e.g., regular past). Performance of natives under noise or memory stress paralleled that of late L2 learners, indicating a role for decoding and memory abilities in explaining poor grammaticality judgment.

The Critical Period Hypothesis: A coat of many colours

Research on age-related effects in L2 development often invokes the idea of a critical period - the postulation of which is customarily referred to as the Critical Period Hypothesis. This paper argues that to speak in terms of the Critical Period Hypothesis is misleading, since there is a vast amount of variation in the way in which the critical period for language acquisition is understood -affecting all the parameters deemed to be theoretically significant and indeed also relating to the ways in which the purported critical period is interpreted in terms of its implications for L2 instruction. The paper concludes that the very fact that there are such diverse and competing versions of the Critical Period Hypothesis of itself undermines its plausibility.

Risk of hearing impairment in pediatric liver transplant recipients: a single center study.

As survival rates following liver transplantation have increased, health care providers must assess the impact of transplantation on dimensions other than traditional medical measures. Hearing impairment may adversely impact social, emotional, cognitive, academic, and speech and language development. We hypothesized that children who undergo liver transplantation are at risk for hearing impairment due to exposure to ototoxic drugs. We conducted a review of 74 children who had undergone liver transplantation between December 1996 and September 2000 at Cincinnati Children's Hospital Medical Center. Hearing was assessed at discharge by an audiologist using age and developmentally appropriate techniques. The principal outcome measure was sensorineural hearing impairment. Independent variables were age at transplantation, United Network for Organ Sharing (UNOS) status at transplantation, primary diagnosis, post-transplant length of hospital stay, days of treatment with aminoglycosides, and days of treatment with loop diuretics. Eleven of 74 children (15%) had sensorineural hearing loss, of whom four had severe to profound hearing loss. Multivariate analyses showed that the adjusted relative risk for hearing loss in patients with hepatoblastoma was 66 and that there was a 5% increase risk for hearing loss for each additional day of hospitalization. Age at transplantation, UNOS status, and days of treatment with loop diuretics or aminoglycosides did not achieve significance in the model. Sensorineural hearing impairment occurs in a subset of pediatric patients following liver transplantation. Patients with hepatoblastoma or those who experience prolonged hospitalization after transplantation are at increased risk. Our observations are of particular importance for pediatric liver transplant recipients since the median age at transplantation is 12-18 months, a critical period for language acquisition.

Late plasticity for language in a child’s non‐dominant hemisphere

The ability of the right hemisphere to sustain the acquisition or the recovery of language after extensive damage to the left hemisphere has been essentially related to the age at the time of injury. Better language abilities are acquired when the insult occurs in early childhood (perinatal insults) compared with later occurrence. However, while previous studies have described the neuropsychological pattern of language development in typical cases, the neural bases of such plasticity remain unexplored. Non-invasive functional MRI (fMRI) is a unique tool to assess the neural correlates of brain plasticity through repeated studies, but the technique has not been widely used in children because of methodological limitations. Plasticity of language was studied in a boy who developed intractable epilepsy related to Rasmussen's syndrome of the left hemisphere at age 5 years 6 months, after normal language acquisition. The first fMRI study at age 6 years 10 months showed left lateralization of language networks during a word fluency task. After left hemispherotomy at age 9 years, the child experienced profound aphasia and alexia, with rapid recovery of receptive language but slower and incomplete recovery of expressive language and reading. Postoperative fMRI at age 10 years 6 months showed a shift of language-related networks to the right during expressive and receptive tasks. Right activation was seen mainly in regions that could not be detected preoperatively, but mirrored those previously found in the left hemisphere (inferior frontal, temporal and parietal cortex), suggesting reorganization in a pre-existing bilateral network. In addition, neuropsychological data of this case support the hypothesis of innately more bilateral distribution of receptive than expressive language. This first serial fMRI study illustrates the great plasticity of the child's brain and the ability of the right hemisphere to take over some expressive language functions, even at a relatively late age. It also suggests a limit for removal of the dominant hemisphere beyond the age of 6 years, a classical limit for the critical period of language acquisition.