Language and reading development in the brain ?· Language and reading development in the brain today:…

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<ul><li><p>J</p><p>R</p><p>Ln</p><p>A</p><p>S(</p><p>RA</p><p>J</p><p>h0</p><p> Pediatr (Rio J). 2016;92(3 Suppl 1):S8---S13</p><p>www.jped.com.br</p><p>EVIEW ARTICLE</p><p>anguage and reading development in the brain today:euromarkers and the case for prediction</p><p>ugusto Buchweitz</p><p>chool of Letters, Instituto do Crebro do Rio Grande do Sul (Inscer), Pontifcia Universidade Catlica do Rio Grande do SulPUCRS), Porto Alegre, RS, Brazil</p><p>eceived 4 January 2016; accepted 15 February 2016vailable online 16 March 2016</p><p>KEYWORDSLanguagedevelopment;Brain imaging;Prediction</p><p>AbstractObjectives: The goal of this article is to provide an account of language development in thebrain using the new information about brain function gleaned from cognitive neuroscience. Thisaccount goes beyond describing the association between language and specific brain areas toadvocate the possibility of predicting language outcomes using brain-imaging data. The goalis to address the current evidence about language development in the brain and prediction oflanguage outcomes.Sources: Recent studies will be discussed in the light of the evidence generated for predictinglanguage outcomes and using new methods of analysis of brain data.Summary of the data: The present account of brain behavior will address: (1) the developmentof a hardwired brain circuit for spoken language; (2) the neural adaptation that follows readinginstruction and fosters the grafting of visual processing areas of the brain onto the hardwiredcircuit of spoken language; and (3) the prediction of language development and the possibilityof translational neuroscience.Conclusions: Brain imaging has allowed for the identification of neural indices (neuromarkers)that reflect typical and atypical language development; the possibility of predicting risk for</p><p>language disorders has emerged. A mandate to develop a bridge between neuroscience andhealth and cognition-related outcomes may pave the way for translational neuroscience. 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.</p><p> Please cite this article as: Buchweitz A. Language and reading development in the brain today: neuromarkers and the case for prediction. Pediatr (Rio J). 2016;92(3 Suppl 1):S8---13.</p><p>E-mail: augusto.buchweitz@pucrs.br</p><p>ttp://dx.doi.org/10.1016/j.jped.2016.01.005021-7557/ 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.</p><p>dx.doi.org/10.1016/j.jped.2016.01.005http://www.jped.com.brhttp://crossmark.crossref.org/dialog/?doi=10.1016/j.jped.2016.01.005&amp;domain=pdfmailto:augusto.buchweitz@pucrs.brdx.doi.org/10.1016/j.jped.2016.01.005</p></li><li><p>Language development today S9</p><p>PALAVRAS-CHAVEDesenvolvimentoda linguagem;Imagem cerebral;Predico</p><p>Desenvolvimento da linguagem e da leitura no crebro atualmente: neuromarcadorese o caso de predico</p><p>ResumoObjetivos: O objetivo deste trabalho apresentar um relato sobre o desenvolvimento dalinguagem no crebro utilizando as novas informaces sobre funco cerebral obtidas na neu-rocincia cognitiva. o relato vai alm da descrico da associaco entre linguagem e reasespecficas do crebro e defende a possibilidade de predizer os resultados de linguagem pormeio de dados de imagens cerebrais. O objetivo tratar das evidncias atuais sobre desen-volvimento da linguagem no crebro e abordar a possibilidade de predico de resultados delinguagem.Fontes: Estudos recentes sero discutidos em face das evidncias geradas pela predico deresultados de linguagem e pelo uso de novos mtodos de anlise de dados cerebrais.Resumo dos dados: Este relato de comportamento cerebral abordar: (1) o desenvolvimentode um circuito cerebral de linguagem falada; (2) a adaptaco neural que segue a instruco daleitura e incentiva a inserco de reas de processamento visual do crebro no circuito delinguagem falada; e (3) a predico do desenvolvimento da linguagem e a possibilidade de umaneurocincia translacional.Concluses: As imagens cerebrais permitiram a identificaco de ndices neurais (neuromar-cadores) que refletem o desenvolvimento da linguagem tpico e atpico; surge a possibilidadede prever o risco de disfunces de linguagem. A responsabilidade de desenvolver uma ligacoentre neurocincia e resultados relacionados a sade e cognico pode abrir o caminho para aneurocincia translacional. 2016 Sociedade Brasileira de Pediatria. Publicado por Elsevier Editora Ltda. Todos os direitosreservados.</p><p>pcieriirigocasst</p><p>N</p><p>TgcTs(rdischarges from neurons and the BOLD signal.16,17 Other MRI</p><p>Introduction</p><p>One of the key challenges for the neurosciences is to becomefaster and more effective at producing evidence thattransforms health and education-related practice. Neuro-scientific studies of neuronal markers hold promise for moresuccessful health and education policies. The obstacles tomaking predictions from brain data involve producing moregeneralizable, robust results; establishing communicationchannels with education and healthcare decision-makersand professionals; and addressing ethical issues that arisefrom making such predictions. The present article focuses ona specific type of evidence: functional brain data obtainedfrom noninvasive brain imaging to predict developmentaland clinical outcomes. Recent studies will be discussed inthe light of the evidence generated for predicting languageoutcomes and of using new methods of analysis of brain data.</p><p>With the advent of magnetic resonance imaging (MRI)and its varied functional and structural procedures, stud-ies of the brain mechanisms that underpin cognition andpsychiatric disorders have flourished.1 Studies using func-tional MRI (fMRI) have unveiled specific neural circuitry andmechanisms for language acquisition, language disorders,and language-related processes.2---4 Language developmenthas been shown to be amenable to investigation by MRI pro-cedures.</p><p>Research on the brains structural and functional indicesthat predict language outcome5---11 may be an effective</p><p>means to translate new evidence into applications.4---12</p><p>However, the influence of the research outside the scien-tific community appears to fall short of its promise.1 The</p><p>ptu</p><p>roduction of generalizable models of clinical and edu-ational outcomes based on these indices (neuromarkers)s an exciting possibility for changing the way health andducation-related decisions benefit from brain imaging. Aecent review13 advocated the application of brain measuresn the prediction of outcomes in several fields, includ-ng education and learning; health-related behaviors andesponses to treatments; and relapse for alcohol, smok-ng, and drug addiction. Prediction was defined as producingeneralizable models that effectively identify outcomes inut-of-sample individuals; in the interest of the present arti-le, this would mean establishing neuromarkers that can bepplied to more diverse populations outside the smaller-ample brain imaging studies.13 Prediction, in this broadense, is the ultimate test of a neuromarker after passing theest of reliable within-subject and in-sample predictions.</p><p>oninvasive brain imaging measures: fMRI</p><p>he present article focuses on evidence from fMRI investi-ations of language development. This technique identifieshanges in metabolism and oxygen levels in the brain.14,15</p><p>hough the increase in metabolism is not a direct mea-ure of neuronal activity, the blood-oxygen level dependentBOLD) signal acquired during fMRI procedures reflects neu-al responses: there is a correlation between electrical</p><p>rocedures, such as diffusion-tensor imaging, used for inves-igations of white matter pathways, are increasingly beingsed in multimodal studies of language processes, disorders,</p></li><li><p>S</p><p>aro3abpia</p><p>Si</p><p>Eaafttp</p><p>obsskrommb</p><p>ce(abwacpmcswctrdtl</p><p>Tmwiist</p><p>t</p><p>fi2gactlaoaediuai</p><p>aiHglfloipaag(nisfwvpobFig. 1 demonstrates the overlap in centers involved forspeech and print processing for Portuguese (adapted fromBuchweitz et al.).29 Similar centers were identified in thestudy of four different languages.</p><p>10 </p><p>nd development.13,18---21 Other methods, such as event-elated potentials, have also effectively predicted languageutcomes: neonatal event-related potentials (as early as6 h after birth) were predictive of language outcomest 8 years of age.22 Multimodal investigations that com-ine procedures eliminate the shortcomings of the differentrocedures.23 A more in-depth discussion of multimodalnvestigation and methods is beyond the scope of the presentrticle.</p><p>poken language development: a resilient process,ts milestones, and hardwired brain circuitry</p><p>arly language development and emerging communicationbilities are fundamental for the development of cognitivend social skills.24 Language development is one of the keyactors associated with the development of mental capital;his means ensuring that each person is given the chanceo achieve their full cognitive potential, and is allowed torosper and flourish within modern society.25</p><p>The United States Committee on Integrating the Sciencef Early Childhood Development produced an evidence-ased report on early brain development, language,ocialization, and self-regulation. In the words of the report:poken language is resilient, literacy is fragile.24 These twoey aspects of oral and written language development,esilience and fragility, have been investigated in the lightf brain imaging. There are language milestones (behavioralarkers) associated with neural signatures of language. Theilestones provide evidence that helps establish predictiverain---behavior relationships for language.</p><p>Spoken language develops without instruction. The pro-ess of development occurs in almost all children despiteconomic and social hardships, as well as lack of instructionbut such hardships influence qualitative and quantitativespects of language and cognitive development).24,26---28 Therain circuits that develop for spoken language are hard-ired in the brain. The components of the language circuitryre associated with levels of auditory comprehension pro-esses; the key centers and processes include: (1) therimary auditory cortex, which processes raw auditory infor-ation; (2) the posterior temporal and inferior parietal</p><p>ortices, which process the systematic organization of wordounds; (3) the middle temporal cortex, which is associatedith accessing word meaning; (4) and the inferior frontalortex, which processes the structure of language. Overhe past 25 years, noninvasive brain imaging has providedobust and replicable evidence about the brain circuits thatevelop for spoken language. It is worth mentioning thathe brain areas involved depend on the granularity of theanguage process being investigated.2,3,9,29,30</p><p>At times there are delays in oral language development.he age at which a child begins to speak is a behavioralarker of such delay. Children usually produce their firstords between 10 and 15 months of age. A delay in speaking</p><p>ndicates atypical language development, and is one of thendicators of risk for reading disorder.31---33 Language mile-</p><p>tones such as age at speaking can be evaluated in terms ofhe typical neural circuits that develop in the child.</p><p>A recent study of early and late talkers identified cor-ical and subcortical markers of children who spoke their</p><p>Fi</p><p>Buchweitz A</p><p>rst words at 1.2 years (early) versus those who spoke at.5 years (late).34 In addition to better performance in lan-uage tests at 8 years of age, early talkers (also at 8 years ofge) showed more activation in subcortical structures asso-iated with the learning of rule-based systems (putamen andhalamus); these subcortical structures are at the basis ofearning new linguistic skills.35,36 Early milestones as simples uttering two to three word sentences are strong indicatorsf language outcome, and the effects of age at speaking aressociated with markers of brain development. Identifyingarly behaviors and understanding the consequences brainevelopment provide a path for cognitive neuroscience tonform early intervention. Brain---behavior relationships helpnderstand the typical interaction between psychologicalnd biological processes, and the missing biological piecesn atypical development.</p><p>The development of spoken language is resilient andlso remarkably similar across languages. Recently, a brainmaging study of four different languages (Spanish, English,ebrew, and Chinese) showed the universality of the lan-uage network in the brain.9 In all languages, the traditionaleft frontal---temporal network of the brain was activatedor listening comprehension, and it was remarkably over-apping. Such findings provide the basis for future modelsf prediction of language outcome across cultures. Theres invariance in structures that develop for speech com-rehension despite the different characteristics of soundnd structure of spoken languages. The study also showed</p><p> common brain signature for reading in the four lan-uages. Despite the significant differences in writing systemsalphabetic and ideographic, for example), the brain sig-ature for reading is largely similar in the four languages;t is also largely constrained by the speech processingystem.9 Earlier studies showed how the centers that adaptor processing print are constrained by the centers hard-ired for spoken language (of course, with the exception ofisual centers). Once children learn to read, the centers forrocessing print are grafted onto a left-lateralized networkf language areas hardwired for spoken language. This haseen shown for English and for Portuguese, for example.29,30</p><p>i...</p></li></ul>