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Abstract
Developmental language disorders (DLD) are prevalent and persistent among school-age children but are often underrecognized. This chapter discusses the ways in which the various components of communication are impacted by these disorders and outlines the differences in expression seen in different languages. Research on biological and psychologic roots of the syndrome is also reviewed. As yet, no single definitive cause has been identified; the disorders are likely to result from a constellation of genetic, biological, and cognitive weaknesses that are influenced by environmental experiences. Basic methods of assessment and differential diagnosis are presented and the principles guiding the development of intervention programs are discussed.
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Affiliation(s)
- Rhea Paul
- Department of Communication Disorders, College of Health Professions, Sacred Heart University, Fairfield, CT, United States.
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Wang J, Rice ML, Booth JR. Syntactic and Semantic Specialization and Integration in 5- to 6-Year-Old Children during Auditory Sentence Processing. J Cogn Neurosci 2020; 32:36-49. [PMID: 31596168 PMCID: PMC8905464 DOI: 10.1162/jocn_a_01477] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Previous studies have found specialized syntactic and semantic processes in the adult brain during language comprehension. Young children have sophisticated semantic and syntactic aspects of language, yet many previous fMRI studies failed to detect this specialization, possibly due to experimental design and analytical methods. In this current study, 5- to 6-year-old children completed a syntactic task and a semantic task to dissociate these two processes. Multivoxel pattern analysis was used to examine the correlation of patterns within a task (between runs) or across tasks. We found that the left middle temporal gyrus showed more similar patterns within the semantic task compared with across tasks, whereas there was no difference in the correlation within the syntactic task compared with across tasks, suggesting its specialization in semantic processing. Moreover, the left superior temporal gyrus showed more similar patterns within both the semantic task and the syntactic task as compared with across tasks, suggesting its role in integration of semantic and syntactic information. In contrast to the temporal lobe, we did not find specialization or integration effects in either the opercular or triangular part of the inferior frontal gyrus. Overall, our study showed that 5- to 6-year-old children have already developed specialization and integration in the temporal lobe, but not in the frontal lobe, consistent with developmental neurocognitive models of language comprehension in typically developing young children.
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Morgan AT, Su M, Reilly S, Conti-Ramsden G, Connelly A, Liégeois FJ. A Brain Marker for Developmental Speech Disorders. J Pediatr 2018; 198:234-239.e1. [PMID: 29705112 DOI: 10.1016/j.jpeds.2018.02.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/21/2018] [Accepted: 02/14/2018] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To characterize the organization of speech- and language-related white matter tracts in children with developmental speech and/or language disorders. STUDY DESIGN We collected magnetic resonance diffusion-weighted imaging data from 41 children, ages 9-11 years, with developmental speech and/or language disorders, and compared them with 45 typically developing controls with the same age range. We used probabilistic tractography of diffusion-weighted imaging to map language (3 segments of arcuate fasciculus, extreme capsule system) and speech motor (corticobulbar) tracts bilaterally. The corticospinal and callosal tracts were used as control regions. We compared the mean fractional anisotropy and diffusivity values between atypical and control groups, covarying for nonverbal IQ. We then examined differences between atypical subgroups: developmental speech disorder (DSD), developmental language disorder, and co-occurring developmental speech and language disorder. RESULTS Fractional anisotropy in the left corticobulbar tract was lower in the DSD than in the control group. Radial and mean diffusivity were higher in the DSD than the developmental language disorder, co-occurring developmental speech and language disorder, or control groups. There were no group differences for any metrics in the language or control tracts. CONCLUSIONS Atypical development of the left corticobulbar tract may be a neural marker for DSD. This finding is in line with reports of speech disorder after left corticobulbar damage in children and adults with brain injury. By contrast, we found no association between diffusion metrics in language-related tracts in developmental language disorder, and changes for language disorders are likely more complex.
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Affiliation(s)
- Angela T Morgan
- Murdoch Children's Research Institute and Royal Children's Hospital, Melbourne, Australia; University of Melbourne, Australia.
| | - Merina Su
- UCL Great Ormond Street Institute of Child Health, London, UK
| | - Sheena Reilly
- Murdoch Children's Research Institute and Royal Children's Hospital, Melbourne, Australia; Griffith University, Gold Coast, Australia
| | | | - Alan Connelly
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
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van Ewijk H, Noordermeer SDS, Heslenfeld DJ, Luman M, Hartman CA, Hoekstra PJ, Faraone SV, Franke B, Buitelaar JK, Oosterlaan J. The influence of comorbid oppositional defiant disorder on white matter microstructure in attention-deficit/hyperactivity disorder. Eur Child Adolesc Psychiatry 2016; 25:701-10. [PMID: 26507746 PMCID: PMC4932146 DOI: 10.1007/s00787-015-0784-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 10/07/2015] [Indexed: 12/22/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) are highly comorbid disorders. ADHD has been associated with altered white matter (WM) microstructure, though the literature is inconsistent, which may be due to differences in the in- or exclusion of participants with comorbid ODD. WM abnormalities in ODD are still poorly understood, and it is unclear whether comorbid ODD in ADHD may have confounded the current ADHD literature. Diffusion Tensor Imaging (DTI) was used to compare fractional anisotropy (FA) and mean diffusivity (MD) between ADHD patients with (n = 42) and without (n = 117) comorbid ODD. All participants were between 8-25 years and groups did not differ in mean age or gender. Follow-up analyses were conducted to examine the role of antisocial behaviour (conduct problems) on FA and MD values in both groups. Comorbid ODD in ADHD was associated with lower FA in left frontotemporal WM, which appeared independent of ADHD symptoms. FA was negatively associated with antisocial behaviour in ADHD + ODD, but not in ADHD-only. Comorbid ODD is associated with WM abnormalities in individuals with ADHD, which appears to be independent of ADHD symptoms. Altered WM microstructure in comorbid ODD may play a role in inconsistencies in the current DTI literature in ADHD. Altered development of these tracts may contribute to social-emotional and cognitive problems in children with oppositional and antisocial behaviour.
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Affiliation(s)
- Hanneke van Ewijk
- Department of Clinical Neuropsychology, Faculty of Psychology and Education, VU University Amsterdam, van der Boechorststraat 1, 1081 BT, Amsterdam, The Netherlands.
| | - Siri D S Noordermeer
- Department of Clinical Neuropsychology, Faculty of Psychology and Education, VU University Amsterdam, van der Boechorststraat 1, 1081 BT, Amsterdam, The Netherlands
| | - Dirk J Heslenfeld
- Department of Clinical Neuropsychology, Faculty of Psychology and Education, VU University Amsterdam, van der Boechorststraat 1, 1081 BT, Amsterdam, The Netherlands
- Department of Cognitive Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Marjolein Luman
- Department of Clinical Neuropsychology, Faculty of Psychology and Education, VU University Amsterdam, van der Boechorststraat 1, 1081 BT, Amsterdam, The Netherlands
| | - Catharina A Hartman
- Department of Psychiatry, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Pieter J Hoekstra
- Department of Psychiatry, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Stephen V Faraone
- Departments of Psychiatry and of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, USA
| | - Barbara Franke
- Departments of Human Genetics and Psychiatry, Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - Jan K Buitelaar
- Department of Cognitive Neuroscience, Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
- Karakter, Child and Adolescent Psychiatry, University Center Nijmegen in Nijmegen, Nijmegen, The Netherlands
| | - J Oosterlaan
- Department of Clinical Neuropsychology, Faculty of Psychology and Education, VU University Amsterdam, van der Boechorststraat 1, 1081 BT, Amsterdam, The Netherlands
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Mayes AK, Reilly S, Morgan AT. Neural correlates of childhood language disorder: a systematic review. Dev Med Child Neurol 2015; 57:706-17. [PMID: 25692930 DOI: 10.1111/dmcn.12714] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/14/2014] [Indexed: 01/28/2023]
Abstract
AIM The neurobiological contributions of childhood language disorder are not well understood. Yet there is increasing evidence that language disorder is associated with differences in brain structure and/or function in core language regions. A key hypothesis has been that children with language disorder do not show the same degree of leftward asymmetry of these regions as observed in typically developing children. We aimed to systematically review structural and functional magnetic resonance imaging (fMRI) studies to examine brain commonalities and differences between children with language disorder and typically developing controls; and differences in leftward asymmetry between these groups. METHOD A systematic review was conducted using MeSH terms synonymous with childhood language disorder and brain MRI methods. The search identified 1443 papers, and 18 articles met the criteria and were appraised for level and quality of evidence. RESULTS Atypical brain structure and function was reported within traditionally recognized language regions across studies, including the inferior frontal gyrus, posterior superior temporal gyrus, and caudate nucleus. The direction of difference (e.g. increased/decreased) was variable, however, likely because of differences in language disorder groups examined and magnetic resonance data acquisition and analysis approaches. As regards asymmetry, there was some evidence of reduction of the anticipated structural and functional leftward asymmetry in frontal language regions in language disorder groups. INTERPRETATION Mounting evidence suggests that children with language disorder have atypical brain structure and function within neural regions integral to language. There is limited support for the hypothesis that children with language disorder show a reduction of leftward structural and/or functional asymmetry in frontal language regions. Interpretation is limited, however, by a high degree of variability in language disorder assessment and phenotype, and in magnetic resonance methodologies. A large-scale magnetic resonance study of brain structure and function is required in a well-defined language disorder population cohort, with replication, to provide confirmatory data on the neural correlates of childhood language disorder.
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Affiliation(s)
- Angela K Mayes
- Murdoch Childrens Research Institute, Melbourne, Vic., Australia
| | - Sheena Reilly
- Murdoch Childrens Research Institute, Melbourne, Vic., Australia.,The University of Melbourne, Melbourne, Vic., Australia
| | - Angela T Morgan
- Murdoch Childrens Research Institute, Melbourne, Vic., Australia.,The University of Melbourne, Melbourne, Vic., Australia
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Sensory Processing Difficulties in Toddlers With Nonorganic Failure-to-Thrive and Feeding Problems. J Pediatr Gastroenterol Nutr 2015; 60:819-24. [PMID: 25564810 DOI: 10.1097/mpg.0000000000000707] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
OBJECTIVES Failure-to-thrive is defined as an abnormally low weight and/or height for age. The term "nonorganic failure-to-thrive" (NOFT) has been used to describe "failure-to-thrive" without an obvious cause underlying the growth failure. The purpose of the present study was to compare sensory processing abilities between toddlers with NOFT and feeding problems and age-matched controls. METHODS Toddlers with NOFT and feeding problems (N = 16) were recruited from the pediatric feeding clinic in a tertiary university hospital, and age-matched controls (N = 16) were recruited from community volunteers. They were evaluated for sensory processing ability using an Infant/Toddler Sensory Profile (ITSP), and for development of cognition, motor skills, and language using the Bayley Scales of Infant Development II and Sequenced Language Scale for Infants. Behavior at mealtime was evaluated using the Behavioral Pediatrics Feeding Assessment Scale. RESULTS In the NOFT with feeding problems group, atypical performances were more frequently observed in 3 of 5 ITSP section items (tactile, vestibular, and oral) compared with those in the control group. Significant delayed development of cognition, motor skills, and language was observed in the NOFT with feeding problems group compared with that in the control group. In addition, children who showed 1 or more atypical performances in ITSP had delayed development in cognition, motor skills, and language. CONCLUSIONS Sensory processing problems were more commonly observed in toddlers with feeding problems and growth deficiency. The present study could provide a preliminary evidence for a possible impact of the sensory processing problems on the feeding difficulties in toddlers with NOFT. Future large studies should be conducted to clarify the relation between sensory processing difficulties and feeding problems in toddlers.
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Contralateral targeting of the corpus callosum in normal and pathological brain function. Trends Neurosci 2015; 38:264-72. [PMID: 25841797 DOI: 10.1016/j.tins.2015.02.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/25/2015] [Accepted: 02/27/2015] [Indexed: 12/14/2022]
Abstract
The corpus callosum connects the two cortical hemispheres of the mammalian brain and is susceptible to structural defects during development, which often result in significant neuropsychological dysfunction. To date, such individuals have been studied primarily with regards to the integrity of the callosal tract at the midline. However, the mechanisms regulating the contralateral targeting of the corpus callosum, after midline crossing has occurred, are less well understood. Recent evidence suggests that defects in contralateral targeting can occur in isolation from midline-tract malformations, and may have significant functional implications. We propose that contralateral targeting is a crucially important and relatively under-investigated event in callosal development, and that defects in this process may constitute an undiagnosed phenotype in several neurological disorders.
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Liégeois FJ, Mahony K, Connelly A, Pigdon L, Tournier JD, Morgan AT. Pediatric traumatic brain injury: language outcomes and their relationship to the arcuate fasciculus. BRAIN AND LANGUAGE 2013; 127:388-98. [PMID: 23756046 PMCID: PMC3988975 DOI: 10.1016/j.bandl.2013.05.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 04/15/2013] [Accepted: 05/07/2013] [Indexed: 05/12/2023]
Abstract
Pediatric traumatic brain injury (TBI) may result in long-lasting language impairments alongside dysarthria, a motor-speech disorder. Whether this co-morbidity is due to the functional links between speech and language networks, or to widespread damage affecting both motor and language tracts, remains unknown. Here we investigated language function and diffusion metrics (using diffusion-weighted tractography) within the arcuate fasciculus, the uncinate fasciculus, and the corpus callosum in 32 young people after TBI (approximately half with dysarthria) and age-matched healthy controls (n=17). Only participants with dysarthria showed impairments in language, affecting sentence formulation and semantic association. In the whole TBI group, sentence formulation was best predicted by combined corpus callosum and left arcuate volumes, suggesting this "dual blow" seriously reduces the potential for functional reorganisation. Word comprehension was predicted by fractional anisotropy in the right arcuate. The co-morbidity between dysarthria and language deficits therefore seems to be the consequence of multiple tract damage.
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Affiliation(s)
- Frédérique J Liégeois
- Developmental Cognitive Neuroscience Unit, University College London, Institute of Child Health, London, United Kingdom.
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Lee JC, Nopoulos PC, Bruce Tomblin J. Abnormal subcortical components of the corticostriatal system in young adults with DLI: a combined structural MRI and DTI study. Neuropsychologia 2013; 51:2154-61. [PMID: 23896446 DOI: 10.1016/j.neuropsychologia.2013.07.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 06/03/2013] [Accepted: 07/01/2013] [Indexed: 11/15/2022]
Abstract
Developmental Language Impairment (DLI) is a neurodevelopmental disorder affecting 12% to 14% of the school-age children in the United States. While substantial studies have shown a wide range of linguistic and non-linguistic difficulty in individuals with DLI, very little is known about the neuroanatomical mechanisms underlying this disorder. In the current study, we examined the subcortical components of the corticostriatal system in young adults with DLI, including the caudate nucleus, the putamen, the nucleus accumbens, the globus pallidus, and the thalamus. Additionally, the four cerebral lobes and the hippocampus were also comprised for an exploratory analysis. We used conventional magnetic resonance imaging (MRI) to measure regional brain volumes, as well as diffusion tensor imaging (DTI) to assess water diffusion anisotropy as quantified by fractional anisotropy (FA). Two groups of participants, one with DLI (n=12) and the other without (n=12), were recruited from a prior behavioral study, and all were matched on age, gender, and handedness. Volumetric analyses revealed region-specific abnormalities in individuals with DLI, showing pathological enlargement bilaterally in the putamen and the nucleus accumbens, and unilaterally in the right globus pallidus after the intracranial volumes were controlled. Regarding the DTI findings, the DLI group showed decreased FA values in the globus pallidus and the thalamus but these significant differences disappeared after controlling for the whole-brain FA value, indicating that microstructural abnormality is diffuse and affects other regions of the brain. Taken together, these results suggest region-specific corticostriatal abnormalities in DLI at the macrostructural level, but corticostriatal abnormalities at the microstructural level may be a part of a diffuse pattern of brain development. Future work is suggested to investigate the relationship between corticostriatal connectivity and individual differences in language development.
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Affiliation(s)
- Joanna C Lee
- Department of Communication Sciences and Disorders, The University of Iowa, Wendell Johnson Speech and Hearing Center, Iowa City, IA 52242, USA.
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Kim CH, Chung CK, Koo BB, Lee JM, Kim JS, Lee SK. Changes in language pathways in patients with temporal lobe epilepsy: diffusion tensor imaging analysis of the uncinate and arcuate fasciculi. World Neurosurg 2011; 75:509-16. [PMID: 21600505 DOI: 10.1016/j.wneu.2010.11.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Revised: 04/26/2010] [Accepted: 11/02/2010] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The language pathways consist of ventral and dorsal systems connected via the uncinate fasciculus and arcuate fasciculus, respectively. Seizures in medial temporal lobe epilepsy (mTLE) affect both tracts. Previous studies, however, have focused on the arcuate fasciculus to explain the language disturbance in mTLE. In contrast, we compared changes in both the uncinate and arcuate fasciculi using diffusion tensor imaging. METHODS Thirteen patients with left mTLE and 12 with right mTLE were studied. The Wada test showed left dominance for language in all these patients. Sixteen healthy right-handed subjects were also studied. The mean fractional anisotropy and mean apparent diffusion coefficient with their lateralization index of two fasciculi were compared between hemispheres and between subjects. RESULTS The mean apparent diffusion coefficient of the arcuate and uncinate fasciculi in both left- and right-mTLE patients increased bilaterally compared with that in healthy subjects. In left mTLE, the fractional anisotropy of the uncinate fasciculus was lower ipsilaterally (P = 0.002) and was significantly lateralized contralaterally (P < 0.001) compared with control subjects, whereas the fractional anisotropy of the arcuate fasciculus showed no lateralization (P = 0.577). In right mTLE, such a difference was not prominent. CONCLUSION The seizure network affects both arcuate and uncinate fasciculi bilaterally in both left- and right-mTLE patients. The change is most prominent in the left uncinate fasciculus in left mTLE.
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Affiliation(s)
- Chi Heon Kim
- Department of Neurosurgery, Seoul National University College of Medicine, Seoul, South Korea
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Moon IJ, Kim EY, Chu H, Chung WH, Cho YS, Hong SH. A new measurement tool for speech development based on Ling's stages of speech acquisition in pediatric cochlear implant recipients. Int J Pediatr Otorhinolaryngol 2011; 75:495-9. [PMID: 21295354 DOI: 10.1016/j.ijporl.2011.01.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 01/03/2011] [Accepted: 01/08/2011] [Indexed: 11/25/2022]
Abstract
OBJECTIVES With the rapid increase of pediatric cochlear implantation (CI), there exists a need for a standardized assessment tool regarding speech and communication skills in children with CI. However, the current testing tools are not appropriate for the longitudinal evaluation of young children after CI. The aims of this study were to describe a progressive testing tool developed for the evaluation of speech acquisition and production in young children who have undergone CI and to examine its validity. METHODS Sixty children younger than six years of age with CI participated in this study. A Korean version of Ling's stages (K-Ling) was developed based on the Ling speech teaching model to longitudinally assess phonologic and phonetic developments in young children after CI. The K-Ling, the Categories of Auditory Performance (CAP), and the Sequenced Language Scale for Infants (SELSI) were performed in the children with CI preoperatively and three, six, and 12 months postoperatively. Correlations among these three testing tools were analyzed. RESULTS Auditory, language, and speech skills assessed using the CAP, SELSI, and K-Ling improved continuously for 12 months in young children following CI. Strong correlations were obtained among K-Ling's level, CAP scores, and the equivalent age of SELSI; correlation indices ranged from 0.540 to 0.800. CONCLUSIONS The K-Ling was a valid evaluation tool regarding speech development in young children who are using CI and who are in the early stages of speech development. Longitudinal assessments of phonetic and phonologic developments may be attainable in young children using the K-Ling.
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Affiliation(s)
- Il Joon Moon
- Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Sungkyunkwan University, School of Medicine, 50 Irwon-dong, Gangnam-gu, 135-710 Seoul, Republic of Korea
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Paul LK. Developmental malformation of the corpus callosum: a review of typical callosal development and examples of developmental disorders with callosal involvement. J Neurodev Disord 2011; 3:3-27. [PMID: 21484594 PMCID: PMC3163989 DOI: 10.1007/s11689-010-9059-y] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 08/13/2010] [Indexed: 12/11/2022] Open
Abstract
This review provides an overview of the involvement of the corpus callosum (CC) in a variety of developmental disorders that are currently defined exclusively by genetics, developmental insult, and/or behavior. I begin with a general review of CC development, connectivity, and function, followed by discussion of the research methods typically utilized to study the callosum. The bulk of the review concentrates on specific developmental disorders, beginning with agenesis of the corpus callosum (AgCC)-the only condition diagnosed exclusively by callosal anatomy. This is followed by a review of several genetic disorders that commonly result in social impairments and/or psychopathology similar to AgCC (neurofibromatosis-1, Turner syndrome, 22q11.2 deletion syndrome, Williams yndrome, and fragile X) and two forms of prenatal injury (premature birth, fetal alcohol syndrome) known to impact callosal development. Finally, I examine callosal involvement in several common developmental disorders defined exclusively by behavioral patterns (developmental language delay, dyslexia, attention-deficit hyperactive disorder, autism spectrum disorders, and Tourette syndrome).
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Affiliation(s)
- Lynn K Paul
- Division of Humanities and Social Sciences, California Institute of Technology, HSS 228-77, Caltech, Pasadena, CA, 91125, USA,
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Sabbah N, Gelbert F, Nioche C, Moroni C, Goasdoué P, Belin C, Sabbah P. Modern concepts of normal language and impairments. Clin Imaging 2008; 32:425-30. [PMID: 19006769 DOI: 10.1016/j.clinimag.2008.02.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Accepted: 02/20/2008] [Indexed: 10/21/2022]
Abstract
Language is a primary factor in comprehending the functional organization of the brain. Starting with the static anatomoclinical model, followed by the limited aphasiological model, functional imaging techniques have allowed a more dynamic approach that adds complexity to the study of the interaction between brain and language, and bespeak the influence of parameters such as age, sex, motivation, and stress.
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Lee A, Kannan V, Hillis AE. The contribution of neuroimaging to the study of language and aphasia. Neuropsychol Rev 2007; 16:171-83. [PMID: 17160697 DOI: 10.1007/s11065-006-9014-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
New structural and functional imaging methods continue to be developed at a rapid pace. In the last 25 years, advanced imaging techniques have provided insights into how language is represented and processed in the brain and how it can be disrupted by damage to, or dysfunction of, various parts of the brain. Imaging studies have also yielded new information regarding how individuals recover language after stroke. We briefly review the strengths and weaknesses of the various radiological methods currently used to study language and aphasia.
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Affiliation(s)
- Andrew Lee
- Department of Neurology, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Phipps 126, Baltimore, MD 21287, USA
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