51
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Serrallach B, Groß C, Bernhofs V, Engelmann D, Benner J, Gündert N, Blatow M, Wengenroth M, Seitz A, Brunner M, Seither S, Parncutt R, Schneider P, Seither-Preisler A. Neural Biomarkers for Dyslexia, ADHD, and ADD in the Auditory Cortex of Children. Front Neurosci 2016; 10:324. [PMID: 27471442 PMCID: PMC4945653 DOI: 10.3389/fnins.2016.00324] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 06/27/2016] [Indexed: 11/13/2022] Open
Abstract
Dyslexia, attention deficit hyperactivity disorder (ADHD), and attention deficit disorder (ADD) show distinct clinical profiles that may include auditory and language-related impairments. Currently, an objective brain-based diagnosis of these developmental disorders is still unavailable. We investigated the neuro-auditory systems of dyslexic, ADHD, ADD, and age-matched control children (N = 147) using neuroimaging, magnetencephalography and psychoacoustics. All disorder subgroups exhibited an oversized left planum temporale and an abnormal interhemispheric asynchrony (10–40 ms) of the primary auditory evoked P1-response. Considering right auditory cortex morphology, bilateral P1 source waveform shapes, and auditory performance, the three disorder subgroups could be reliably differentiated with outstanding accuracies of 89–98%. We therefore for the first time provide differential biomarkers for a brain-based diagnosis of dyslexia, ADHD, and ADD. The method allowed not only allowed for clear discrimination between two subtypes of attentional disorders (ADHD and ADD), a topic controversially discussed for decades in the scientific community, but also revealed the potential for objectively identifying comorbid cases. Noteworthy, in children playing a musical instrument, after three and a half years of training the observed interhemispheric asynchronies were reduced by about 2/3, thus suggesting a strong beneficial influence of music experience on brain development. These findings might have far-reaching implications for both research and practice and enable a profound understanding of the brain-related etiology, diagnosis, and musically based therapy of common auditory-related developmental disorders and learning disabilities.
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Affiliation(s)
- Bettina Serrallach
- Department of Neurology, Section of Biomagnetism, University Hospital HeidelbergHeidelberg, Germany; Division of Neuroradiology, University Hospital HeidelbergHeidelberg, Germany; Division of Radiology and Nuclear Medicine, Kantonsspital St. GallenSt. Gallen, Switzerland
| | - Christine Groß
- Department of Neurology, Section of Biomagnetism, University Hospital Heidelberg Heidelberg, Germany
| | | | - Dorte Engelmann
- Department of Neurology, Section of Biomagnetism, University Hospital Heidelberg Heidelberg, Germany
| | - Jan Benner
- Department of Neurology, Section of Biomagnetism, University Hospital HeidelbergHeidelberg, Germany; Division of Neuroradiology, Department of Radiology, University of Basel HospitalBasel, Switzerland
| | - Nadine Gündert
- Department of Neurology, Section of Biomagnetism, University Hospital Heidelberg Heidelberg, Germany
| | - Maria Blatow
- Division of Neuroradiology, Department of Radiology, University of Basel Hospital Basel, Switzerland
| | - Martina Wengenroth
- Department of Neuroradiology, University Hospital Lübeck Lübeck, Germany
| | - Angelika Seitz
- Department of Pediatric Neurology, University Hospital Heidelberg Heidelberg, Germany
| | - Monika Brunner
- Phoniatrics and Pedaudiology, University Hospital Heidelberg Heidelberg, Germany
| | - Stefan Seither
- Institute of Psychology, University of GrazGraz, Austria; BioTechMed GrazGraz, Austria
| | - Richard Parncutt
- Centre for Systematic Musicology, University of Graz Graz, Austria
| | - Peter Schneider
- Department of Neurology, Section of Biomagnetism, University Hospital HeidelbergHeidelberg, Germany; Division of Neuroradiology, University Hospital HeidelbergHeidelberg, Germany
| | - Annemarie Seither-Preisler
- Department of Neurology, Section of Biomagnetism, University Hospital HeidelbergHeidelberg, Germany; Division of Neuroradiology, University Hospital HeidelbergHeidelberg, Germany; Institute of Psychology, University of GrazGraz, Austria; BioTechMed GrazGraz, Austria; Centre for Systematic Musicology, University of GrazGraz, Austria
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52
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Molinaro N, Lizarazu M, Lallier M, Bourguignon M, Carreiras M. Out-of-synchrony speech entrainment in developmental dyslexia. Hum Brain Mapp 2016; 37:2767-83. [PMID: 27061643 DOI: 10.1002/hbm.23206] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 03/07/2016] [Accepted: 03/24/2016] [Indexed: 11/09/2022] Open
Abstract
Developmental dyslexia is a reading disorder often characterized by reduced awareness of speech units. Whether the neural source of this phonological disorder in dyslexic readers results from the malfunctioning of the primary auditory system or damaged feedback communication between higher-order phonological regions (i.e., left inferior frontal regions) and the auditory cortex is still under dispute. Here we recorded magnetoencephalographic (MEG) signals from 20 dyslexic readers and 20 age-matched controls while they were listening to ∼10-s-long spoken sentences. Compared to controls, dyslexic readers had (1) an impaired neural entrainment to speech in the delta band (0.5-1 Hz); (2) a reduced delta synchronization in both the right auditory cortex and the left inferior frontal gyrus; and (3) an impaired feedforward functional coupling between neural oscillations in the right auditory cortex and the left inferior frontal regions. This shows that during speech listening, individuals with developmental dyslexia present reduced neural synchrony to low-frequency speech oscillations in primary auditory regions that hinders higher-order speech processing steps. The present findings, thus, strengthen proposals assuming that improper low-frequency acoustic entrainment affects speech sampling. This low speech-brain synchronization has the strong potential to cause severe consequences for both phonological and reading skills. Interestingly, the reduced speech-brain synchronization in dyslexic readers compared to normal readers (and its higher-order consequences across the speech processing network) appears preserved through the development from childhood to adulthood. Thus, the evaluation of speech-brain synchronization could possibly serve as a diagnostic tool for early detection of children at risk of dyslexia. Hum Brain Mapp 37:2767-2783, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Nicola Molinaro
- BCBL, Basque Center on Cognition, Brain and Language, San Sebastian, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Mikel Lizarazu
- BCBL, Basque Center on Cognition, Brain and Language, San Sebastian, Spain
| | - Marie Lallier
- BCBL, Basque Center on Cognition, Brain and Language, San Sebastian, Spain
| | - Mathieu Bourguignon
- BCBL, Basque Center on Cognition, Brain and Language, San Sebastian, Spain.,Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, Finland
| | - Manuel Carreiras
- BCBL, Basque Center on Cognition, Brain and Language, San Sebastian, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
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53
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Altered hemispheric lateralization of white matter pathways in developmental dyslexia: Evidence from spherical deconvolution tractography. Cortex 2016; 76:51-62. [DOI: 10.1016/j.cortex.2015.12.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 05/13/2015] [Accepted: 12/22/2015] [Indexed: 01/18/2023]
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54
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Kong R, Shao S, Wang J, Zhang X, Guo S, Zou L, Zhong R, Lou J, Zhou J, Zhang J, Song R. Genetic variant in DIP2A gene is associated with developmental dyslexia in Chinese population. Am J Med Genet B Neuropsychiatr Genet 2016; 171B:203-8. [PMID: 26452339 DOI: 10.1002/ajmg.b.32392] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/02/2015] [Indexed: 11/07/2022]
Abstract
Increasing evidence suggests that there is a substantial heritable component including several risk loci and candidate genes for developmental dyslexia (DD). DIP2A has been identified to be partially deleted on chromosome region 21q22.3, which cosegregates with DD. And it fits into a theoretical molecular network of DD implicated in the development of DD. Compared with some DD candidate genes that have been extensively studied (e.g., DYX1C1, DCDC2, KIAA0319, and ROBO1), very little is known about the association between candidate gene DIP2A and DD susceptibility. And given the linguistic and genetic differences between Chinese and other Western populations, it is worthwhile validating the association of DIP2A in Chinese dyslexic children. Here, we investigated two genetic variants, selected by bioinformatics analysis, in DIP2A in a Chinese population with 409 dyslexic cases and 410 healthy controls. We observed a significantly increased DD risk associated with rs2255526 G allele (OR = 1.297, 95% CI = 1.036-1.623, Padjusted = 0.023) and GG genotypes (OR = 1.833, 95% CI = 1.043-3.223, Padjusted = 0.035), compared with their wild-type counterparts. In addition, it was marginally significantly associated with DD under the recessive model (OR = 1.677, 95% CI = 0.967-2.908, Padjusted = 0.066) and the dominant model (OR = 1.314, 95% CI = 0.992-1.741, Padjusted = 0.057). However, we found no evidence of an association of SNP rs16979358 with DD. In conclusion, this study showed that a genetic variant in the DIP2A gene was associated with increased DD risk in China.
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Affiliation(s)
- Rui Kong
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shanshan Shao
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jia Wang
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaohui Zhang
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shengnan Guo
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Zou
- Department of Health Care, Baoan Maternal and Child Health Hospital, Shenzhen, China
| | - Rong Zhong
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiao Lou
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jie Zhou
- Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, District of Columbia
| | - Jiajia Zhang
- Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, District of Columbia
| | - Ranran Song
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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55
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Representation of spectro-temporal features of spoken words within the P1-N1-P2 and T-complex of the auditory evoked potentials (AEP). Neurosci Lett 2015; 614:119-26. [PMID: 26700876 DOI: 10.1016/j.neulet.2015.12.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 10/22/2015] [Accepted: 12/10/2015] [Indexed: 01/10/2023]
Abstract
The purpose of the study was to determine whether P1-N1-P2 and T-complex morphology reflect spectro-temporal features within spoken words that approximate the natural variation of a speaker and whether waveform morphology is reliable at group and individual levels, necessary for probing auditory deficits. The P1-N1-P2 and T-complex to the syllables /pət/ and /sət/ within 70 natural word productions each were examined. EEG was recorded while participants heard nonsense word pairs and performed a syllable identification task to the second word in the pairs. Single trial auditory evoked potentials (AEP) to the first words were analyzed. Results found P1-N1-P2 and T-complex to reflect spectral and temporal feature processing. Also, results identified preliminary benchmarks for single trial response variability for individual subjects for sensory processing between 50 and 600ms. P1-N1-P2 and T-complex, at least at group level, may serve as phenotypic signatures to identify deficits in spectro-temporal feature recognition and to determine area of deficit, the superior temporal plane or lateral superior temporal gyrus.
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56
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Xia Z, Hoeft F, Zhang L, Shu H. Neuroanatomical anomalies of dyslexia: Disambiguating the effects of disorder, performance, and maturation. Neuropsychologia 2015; 81:68-78. [PMID: 26679527 DOI: 10.1016/j.neuropsychologia.2015.12.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 09/17/2015] [Accepted: 12/06/2015] [Indexed: 12/26/2022]
Abstract
An increasing body of studies has revealed neuroanatomical impairments in developmental dyslexia. However, whether these structural anomalies are driven by dyslexia (disorder-specific effects), absolute reading performance (performance-dependent effects), and/or further influenced by age (maturation-sensitive effects) remains elusive. To help disentangle these sources, the current study used a novel disorder (dyslexia vs. control) by maturation (younger vs. older) factorial design in 48 Chinese children who were carefully matched. This design not only allows for direct comparison between dyslexics versus controls matched for chronological age and reading ability, but also enables examination of the influence of maturation and its interaction with dyslexia. Voxel-based morphometry (VBM) showed that dyslexic children had reduced regional gray matter volume in the left temporo-parietal cortex (spanning over Heschl's gyrus, planum temporale and supramarginal gyrus), middle frontal gyrus, superior occipital gyrus, and reduced regional white matter in bilateral parieto-occipital regions (left cuneus and right precuneus) compared with both age-matched and reading-level matched controls. Therefore, maturational stage-invariant neurobiological signatures of dyslexia were found in brain regions that have been associated with impairments in the auditory/phonological and attentional systems. On the other hand, maturational stage-dependent effects on dyslexia were observed in three regions (left ventral occipito-temporal cortex, left dorsal pars opercularis and genu of the corpus callosum), all of which were previously reported to be involved in fluent reading and its development. These striking dissociations collectively suggest potential atypical developmental trajectories of dyslexia, where underlying mechanisms are currently unknown but may be driven by interactions between genetic and/or environmental factors. In summary, this is the first study to disambiguate maturational stage on neuroanatomical anomalies of dyslexia in addition to the effects of disorder, reading performance and maturational stage on neuroanatomical anomalies of dyslexia, despite the limitation of a relatively small sample-size. These results will hopefully encourage future research to place greater emphasis on taking a developmental perspective to dyslexia, which may, in turn, further our understanding of the etiological basis of this neurodevelopmental disorder, and ultimately optimize early identification and remediation.
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Affiliation(s)
- Zhichao Xia
- State Key Lab of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China; Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing 100875, China; Division of Child and Adolescent Psychiatry, Department of Psychiatry, UCSF, 401 Parnassus Ave, San Francisco, CA 94143, USA
| | - Fumiko Hoeft
- Division of Child and Adolescent Psychiatry, Department of Psychiatry, UCSF, 401 Parnassus Ave, San Francisco, CA 94143, USA; Haskins Laboratories, 300 George St #900, New Haven, CT 06511, USA; Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi Shinjuku Tokyo, 160-8582, Japan
| | - Linjun Zhang
- College of Chinese Studies, Beijing Language and Culture University, Beijing 100083, China
| | - Hua Shu
- State Key Lab of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China; Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing 100875, China.
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57
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A prolonged maturational time course in brain development for cortical processing of temporal modulations. Clin Neurophysiol 2015; 127:994-998. [PMID: 26480832 DOI: 10.1016/j.clinph.2015.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 08/27/2015] [Accepted: 09/01/2015] [Indexed: 11/21/2022]
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58
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Lizarazu M, Lallier M, Molinaro N, Bourguignon M, Paz-Alonso PM, Lerma-Usabiaga G, Carreiras M. Developmental evaluation of atypical auditory sampling in dyslexia: Functional and structural evidence. Hum Brain Mapp 2015; 36:4986-5002. [PMID: 26356682 DOI: 10.1002/hbm.22986] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 08/21/2015] [Accepted: 08/25/2015] [Indexed: 11/07/2022] Open
Abstract
Whether phonological deficits in developmental dyslexia are associated with impaired neural sampling of auditory information at either syllabic- or phonemic-rates is still under debate. In addition, whereas neuroanatomical alterations in auditory regions have been documented in dyslexic readers, whether and how these structural anomalies are linked to auditory sampling and reading deficits remains poorly understood. In this study, we measured auditory neural synchronization at different frequencies corresponding to relevant phonological spectral components of speech in children and adults with and without dyslexia, using magnetoencephalography. Furthermore, structural MRI was used to estimate cortical thickness of the auditory cortex of participants. Dyslexics showed atypical brain synchronization at both syllabic (slow) and phonemic (fast) rates. Interestingly, while a left hemispheric asymmetry in cortical thickness was functionally related to a stronger left hemispheric lateralization of neural synchronization to stimuli presented at the phonemic rate in skilled readers, the same anatomical index in dyslexics was related to a stronger right hemispheric dominance for neural synchronization to syllabic-rate auditory stimuli. These data suggest that the acoustic sampling deficit in development dyslexia might be linked to an atypical specialization of the auditory cortex to both low and high frequency amplitude modulations.
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Affiliation(s)
- Mikel Lizarazu
- Basque Center on Cognition, Brain and Language (BCBL), Donostia/San Sebastian, Spain
| | - Marie Lallier
- Basque Center on Cognition, Brain and Language (BCBL), Donostia/San Sebastian, Spain
| | - Nicola Molinaro
- Basque Center on Cognition, Brain and Language (BCBL), Donostia/San Sebastian, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Mathieu Bourguignon
- Basque Center on Cognition, Brain and Language (BCBL), Donostia/San Sebastian, Spain.,Department of Neuroscience and Biomedical Engineering, Aalto University, Espoo, Finland
| | - Pedro M Paz-Alonso
- Basque Center on Cognition, Brain and Language (BCBL), Donostia/San Sebastian, Spain
| | | | - Manuel Carreiras
- Basque Center on Cognition, Brain and Language (BCBL), Donostia/San Sebastian, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
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59
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The Roles of Genes in the Neuronal Migration and Neurite Outgrowth Network in Developmental Dyslexia: Single- and Multiple-Risk Genetic Variants. Mol Neurobiol 2015; 53:3967-3975. [PMID: 26184631 DOI: 10.1007/s12035-015-9334-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 07/01/2015] [Indexed: 01/21/2023]
Abstract
Abnormal regulation of neural migration and neurite growth is thought to be an important feature of developmental dyslexia (DD). We investigated 16 genetic variants, selected by bioinformatics analyses, in six key genes in the neuronal migration and neurite outgrowth network in a Chinese population. We first observed that KIAA0319L rs28366021, KIAA0319 rs4504469, and DOCK4 rs2074130 were significantly associated with DD risk after false discovery rate (FDR) adjustment for multiple comparisons (odds ratio (OR) = 0.672, 95 % confidence interval (CI) = 0.505-0.894, P = 0.006; OR = 1.608, 95 % CI = 1.174-2.203, P = 0.003; OR = 1.681, 95 % CI = 1.203-2.348, P = 0.002). The following classification and regression tree (CART) analysis revealed a prediction value of gene-gene interactions among DOCK4 rs2074130, KIAA0319 rs4504469, DCDC2 rs2274305, and KIAA0319L rs28366021 variants. Compared with the lowest risk carriers of the combination of rs2074130 CC, rs4504469 CC, and rs2274305 GG genotype, individuals carrying the combined genotypes of rs2074130 CC, rs4504469 CT or TT, and rs28366021 GG had a significantly increased risk for DD (OR = 2.492, 95 % CI = 1.447-4.290, P = 0.001); individuals with the combination of rs2074130 CT or TT and rs28366021 GG genotype exhibited the highest risk for DD (OR = 2.770, 95 % CI = 2.265-6.276, P = 0.000). A significant dose effect was observed among these four variants (P for trend = 0.000). In summary, this study supports the importance of single- and multiple-risk variants in this network in DD susceptibility in China.
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60
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Skeide MA, Kirsten H, Kraft I, Schaadt G, Müller B, Neef N, Brauer J, Wilcke A, Emmrich F, Boltze J, Friederici AD. Genetic dyslexia risk variant is related to neural connectivity patterns underlying phonological awareness in children. Neuroimage 2015; 118:414-21. [PMID: 26080313 DOI: 10.1016/j.neuroimage.2015.06.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 04/29/2015] [Accepted: 06/06/2015] [Indexed: 11/30/2022] Open
Abstract
Phonological awareness is the best-validated predictor of reading and spelling skill and therefore highly relevant for developmental dyslexia. Prior imaging genetics studies link several dyslexia risk genes to either brain-functional or brain-structural factors of phonological deficits. However, coherent evidence for genetic associations with both functional and structural neural phenotypes underlying variation in phonological awareness has not yet been provided. Here we demonstrate that rs11100040, a reported modifier of SLC2A3, is related to the functional connectivity of left fronto-temporal phonological processing areas at resting state in a sample of 9- to 12-year-old children. Furthermore, we provide evidence that rs11100040 is related to the fractional anisotropy of the arcuate fasciculus, which forms the structural connection between these areas. This structural connectivity phenotype is associated with phonological awareness, which is in turn associated with the individual retrospective risk scores in an early dyslexia screening as well as to spelling. These results suggest a link between a dyslexia risk genotype and a functional as well as a structural neural phenotype, which is associated with a phonological awareness phenotype. The present study goes beyond previous work by integrating genetic, brain-functional and brain-structural aspects of phonological awareness within a single approach. These combined findings might be another step towards a multimodal biomarker for developmental dyslexia.
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Affiliation(s)
- Michael A Skeide
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103 Leipzig, Germany.
| | - Holger Kirsten
- Fraunhofer Institute for Cell Therapy and Immunology, Perlickstraße 1, 04103 Leipzig, Germany; Institute for Medical Informatics, Statistics and Epidemiology and LIFE-Leipzig Research Center for Civilization Diseases, Universität Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany
| | - Indra Kraft
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103 Leipzig, Germany
| | - Gesa Schaadt
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103 Leipzig, Germany; Department of Psychology, Humboldt-Universität zu Berlin, Rudower Chaussee 18, 12489 Berlin, Germany
| | - Bent Müller
- Fraunhofer Institute for Cell Therapy and Immunology, Perlickstraße 1, 04103 Leipzig, Germany
| | - Nicole Neef
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103 Leipzig, Germany
| | - Jens Brauer
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103 Leipzig, Germany
| | - Arndt Wilcke
- Fraunhofer Institute for Cell Therapy and Immunology, Perlickstraße 1, 04103 Leipzig, Germany
| | - Frank Emmrich
- Fraunhofer Institute for Cell Therapy and Immunology, Perlickstraße 1, 04103 Leipzig, Germany; Translational Center for Regenerative Medicine, Philipp-Rosenthal-Straße 55, 04103 Leipzig, Germany
| | - Johannes Boltze
- Fraunhofer Institute for Cell Therapy and Immunology, Perlickstraße 1, 04103 Leipzig, Germany; Translational Center for Regenerative Medicine, Philipp-Rosenthal-Straße 55, 04103 Leipzig, Germany; Massachusetts General Hospital and Harvard Medical School, Neurovascular Regulation Laboratory, 149 13th Street, Charlestown, MA 02129, USA
| | - Angela D Friederici
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103 Leipzig, Germany
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61
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Dalrymple KA, Duchaine B. Impaired face detection may explain some but not all cases of developmental prosopagnosia. Dev Sci 2015; 19:440-51. [DOI: 10.1111/desc.12311] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 03/04/2015] [Indexed: 11/29/2022]
Affiliation(s)
| | - Brad Duchaine
- Department of Psychological and Brain Sciences; Dartmouth College; USA
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62
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Kraft I, Cafiero R, Schaadt G, Brauer J, Neef NE, Müller B, Kirsten H, Wilcke A, Boltze J, Friederici AD, Skeide MA. Cortical differences in preliterate children at familiar risk of dyslexia are similar to those observed in dyslexic readers. Brain 2015; 138:e378. [DOI: 10.1093/brain/awv036] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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63
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Goswami U. Sensory theories of developmental dyslexia: three challenges for research. Nat Rev Neurosci 2014; 16:43-54. [PMID: 25370786 DOI: 10.1038/nrn3836] [Citation(s) in RCA: 236] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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64
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Norton ES, Beach SD, Gabrieli JDE. Neurobiology of dyslexia. Curr Opin Neurobiol 2014; 30:73-8. [PMID: 25290881 DOI: 10.1016/j.conb.2014.09.007] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/15/2014] [Accepted: 09/18/2014] [Indexed: 10/24/2022]
Abstract
Dyslexia is one of the most common learning disabilities, yet its brain basis and core causes are not yet fully understood. Neuroimaging methods, including structural and functional magnetic resonance imaging, diffusion tensor imaging, and electrophysiology, have significantly contributed to knowledge about the neurobiology of dyslexia. Recent studies have discovered brain differences before formal instruction that likely encourage or discourage learning to read effectively, distinguished between brain differences that likely reflect the etiology of dyslexia versus brain differences that are the consequences of variation in reading experience, and identified distinct neural networks associated with specific psychological factors that are associated with dyslexia.
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Affiliation(s)
- Elizabeth S Norton
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, United States.
| | - Sara D Beach
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, United States
| | - John D E Gabrieli
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, United States; Institute for Medical Engineering & Science, Cambridge, MA 02139, United States
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65
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Halliday LF, Barry JG, Hardiman MJ, Bishop DVM. Late, not early mismatch responses to changes in frequency are reduced or deviant in children with dyslexia: an event-related potential study. J Neurodev Disord 2014; 6:21. [PMID: 25110526 PMCID: PMC4126817 DOI: 10.1186/1866-1955-6-21] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 07/11/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Developmental disorders of oral and written language have been linked to deficits in the processing of auditory information. However, findings have been inconsistent, both for behavioural and electrophysiological measures. METHODS In this study, we examined event-related potentials (ERPs) in 20 6- to 14-year-old children with developmental dyslexia and 20 age-matched controls, divided into younger (6-11 years, n = 10) and older (11-14 years, n = 10) age bands. We focused on early (mismatch negativity; MMN) and late (late discriminative negativity; LDN) conventional mismatch responses and associated measures derived from time-frequency analysis (inter-trial coherence and event-related spectral perturbation). Responses were elicited using an auditory oddball task, whereby a stream of 1000-Hz standards was interspersed with rare large (1,200 Hz) and small (1,030 Hz) frequency deviants. RESULTS Conventional analyses revealed no significant differences between groups in the size of the MMN to either large or small frequency deviants. However, the younger age band of children with dyslexia showed an enhanced inter-trial coherence in the theta frequency band over the time window corresponding to the MMN to small deviants. By contrast, these same children showed a reduced-amplitude LDN for the small deviants relative to their age-matched controls, whilst the older children with dyslexia showed a shorter and less intense period of event-related desynchronization over this time window. CONCLUSIONS Initial detection and discrimination of auditory frequency change appears normal or even enhanced in children with dyslexia. Rather, deficits in late-stage auditory processing appear to be a feature of this population.
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Affiliation(s)
- Lorna F Halliday
- Division of Psychology and Language Sciences, University College London, 2 Wakefield Street, London WC1N 1PF, UK
- Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, UK
| | - Johanna G Barry
- MRC Institute of Hearing Research Nottingham Clinical Section, Eye, Ear Nose & Throat Centre, Queens Medical Centre, Nottingham NG7 2UH, UK
- Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, UK
| | - Mervyn J Hardiman
- Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, UK
| | - Dorothy VM Bishop
- Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, UK
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66
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van Bergen E, van der Leij A, de Jong PF. The intergenerational multiple deficit model and the case of dyslexia. Front Hum Neurosci 2014; 8:346. [PMID: 24920944 PMCID: PMC4041008 DOI: 10.3389/fnhum.2014.00346] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 05/07/2014] [Indexed: 12/20/2022] Open
Abstract
Which children go on to develop dyslexia? Since dyslexia has a multifactorial etiology, this question can be restated as: what are the factors that put children at high risk for developing dyslexia? It is argued that a useful theoretical framework to address this question is Pennington’s (2006) multiple deficit model (MDM). This model replaces models that attribute dyslexia to a single underlying cause. Subsequently, the generalist genes hypothesis for learning (dis)abilities (Plomin and Kovas, 2005) is described and integrated with the MDM. Next, findings are presented from a longitudinal study with children at family risk for dyslexia. Such studies can contribute to testing and specifying the MDM. In this study, risk factors at both the child and family level were investigated. This led to the proposed intergenerational MDM, in which both parents confer liability via intertwined genetic and environmental pathways. Future scientific directions are discussed to investigate parent-offspring resemblance and transmission patterns, which will shed new light on disorder etiology.
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Affiliation(s)
- Elsje van Bergen
- Department of Experimental Psychology, University of Oxford Oxford, UK
| | - Aryan van der Leij
- Research Institute of Child Development and Education, University of Amsterdam Amsterdam, Netherlands
| | - Peter F de Jong
- Research Institute of Child Development and Education, University of Amsterdam Amsterdam, Netherlands
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67
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Margari L, Buttiglione M, Craig F, Cristella A, de Giambattista C, Matera E, Operto F, Simone M. Neuropsychopathological comorbidities in learning disorders. BMC Neurol 2013; 13:198. [PMID: 24330722 PMCID: PMC3878726 DOI: 10.1186/1471-2377-13-198] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 12/04/2013] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Learning Disorders (LD) are complex diseases that affect about 2-10% of the school-age population. We performed neuropsychological and psychopathological evaluation, in order to investigate comorbidity in children with LD. METHODS Our sample consisted of 448 patients from 7 to 16 years of age with a diagnosis of LD, divided in two subgroups: Specific Learning Disorders (SLD), including reading, writing, mathematics disorders, and Learning Disorders Not Otherwise Specified (LD NOS). RESULTS Comorbidity with neuropsychopathologies was found in 62.2% of the total sample. In the LSD subgroup, ADHD was present in 33%, Anxiety Disorder in 28.8%, Developmental Coordination Disorder in 17.8%, Language Disorder in 11% and Mood Disorder in 9.4% of patients. In LD NOS subgroup, Language Disorder was present in 28.6%, Developmental Coordination Disorder in 27.5%, ADHD in 25.4%, Anxiety Disorder in 16.4%, Mood Disorder in 2.1% of patients. A statistically significant presence was respectively found for Language and Developmental Coordination Disorder comorbidity in LD NOS and for ADHD, mood and anxiety disorder comorbidity in SLD subgroup. CONCLUSIONS The different findings emerging in this study suggested to promote further investigations to better define the difference between SLD and LD NOS, in order to improve specific interventions to reduce the long range consequences.
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Affiliation(s)
- Lucia Margari
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
| | - Maura Buttiglione
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
| | - Francesco Craig
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
| | - Arcangelo Cristella
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
| | - Concetta de Giambattista
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
| | - Emilia Matera
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
| | - Francesca Operto
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
| | - Marta Simone
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neurosciences and Sense Organs of the “Aldo Moro” University of Bari, Piazza Giulio Cesare 1, Bari, Italy
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68
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Protopapas A. From temporal processing to developmental language disorders: mind the gap. Philos Trans R Soc Lond B Biol Sci 2013; 369:20130090. [PMID: 24324245 PMCID: PMC3866431 DOI: 10.1098/rstb.2013.0090] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The 'rapid temporal processing' and the 'temporal sampling framework' hypotheses have been proposed to account for the deficits in language and literacy development seen in specific language impairment and dyslexia. This paper reviews these hypotheses and concludes that the proposed causal chains between the presumed auditory processing deficits and the observed behavioural manifestation of the disorders are vague and not well established empirically. Several problems and limitations are identified. Most data concern correlations between distantly related tasks, and there is considerable heterogeneity and variability in performance as well as concerns about reliability and validity. Little attention is paid to the distinction between ostensibly perceptual and metalinguistic tasks or between implicit and explicit modes of performance, yet measures are assumed to be pure indicators of underlying processes or representations. The possibility that diagnostic categories do not refer to causally and behaviourally homogeneous groups needs to be taken seriously, taking into account genetic and neurodevelopmental studies to construct multiple-risk models. To make progress in the field, cognitive models of each task must be specified, including performance domains that are predicted to be deficient versus intact, testing multiple indicators of latent constructs and demonstrating construct reliability and validity.
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Affiliation(s)
- Athanassios Protopapas
- Department of Philosophy and History of Science, University of Athens, Ano Ilissia Campus, Zografos 157 71, Greece
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69
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A functionally guided approach to the morphometry of occipitotemporal regions in developmental dyslexia: evidence for differential effects in boys and girls. J Neurosci 2013; 33:11296-301. [PMID: 23825432 DOI: 10.1523/jneurosci.5854-12.2013] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Developmental dyslexia is a learning disability that specifically affects reading acquisition. Cortical anomalies and gray matter volume differences in various temporal regions have been reported in dyslexic subjects compared with controls. However, consistency between studies is lacking. In the present experiments, we focused our structural analyses on the ventral occipitotemporal regions, defined by their functional response to visual categories. We applied a subject-by-subject functionally guided approach on a total of 76 participants (31 dyslexic children). Cortical thickness was estimated for each participant around his/her peak of specific functional activation to visual words, faces, or places. Results from two independent datasets showed a reduction in thickness in dyslexic children compared with controls in the region responsive to words, in the left hemisphere. Additionally, a gender-by-diagnosis interaction was observed at the same location, due to differences in girls only. To avoid the potential confound of reading level, we also contrasted dyslexic and control children matched for reading performance, and we observed a similar difference, although in a smaller extent of cortex. The present study thus provides the first account of a focal cortical thickness reduction in dyslexia in the subregion of ventral occipitotemporal cortex specifically responsive to visual words, when age, gender, and reading performance are taken into account.
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Lehongre K, Morillon B, Giraud AL, Ramus F. Impaired auditory sampling in dyslexia: further evidence from combined fMRI and EEG. Front Hum Neurosci 2013; 7:454. [PMID: 23950742 PMCID: PMC3738857 DOI: 10.3389/fnhum.2013.00454] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 07/22/2013] [Indexed: 12/19/2022] Open
Abstract
The aim of the present study was to explore auditory cortical oscillation properties in developmental dyslexia. We recorded cortical activity in 17 dyslexic participants and 15 matched controls using simultaneous EEG and fMRI during passive viewing of an audiovisual movie. We compared the distribution of brain oscillations in the delta, theta and gamma ranges over left and right auditory cortices. In controls, our results are consistent with the hypothesis that there is a dominance of gamma oscillations in the left hemisphere and a dominance of delta-theta oscillations in the right hemisphere. In dyslexics, we did not find such an interaction, but similar oscillations in both hemispheres. Thus, our results confirm that the primary cortical disruption in dyslexia lies in a lack of hemispheric specialization for gamma oscillations, which might disrupt the representation of or the access to phonemic units.
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Affiliation(s)
- Katia Lehongre
- Research Center of the Brain and Spine Institute (CRICM), Hôpital de la Pitié-Salpêtrière Paris, France
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71
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Ciriaco A, Russo A, Monzani D, Genovese E, Benincasa P, Caffo E, Pini LA. A preliminary study on the relationship between central auditory processing and childhood primary headaches in the intercritical phase. J Headache Pain 2013; 14:69. [PMID: 23937666 PMCID: PMC3751182 DOI: 10.1186/1129-2377-14-69] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Accepted: 06/20/2013] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Recently, an increasing number of articles have appeared on central auditory processing disorders, but in the literature there is only one study that evaluated the possible correlation between migraine in the critical phase and central auditory processing. The aim of our study was to assess the correlation between auditory processing information and childhood primary headaches in the intercritical phase. METHODS This is an observational study. We enrolled 54 patients, 30 with primary headache (migraine and tension headache) and 24 normal controls, matched for sex and age. The mean age at first observation was 9 years 10 months; the duration of observational follow-up was 2 years. Both groups had normal audiological and neurological profiles, normal peripheral hearing acuity and normal cognitive and behavioral skills. We excluded patients who had undergone pharmacological prophylactic treatment for headaches in the 6 months preceding the study and subjects with a frequency of headache lower than one every two months. After enrolment, both groups were analyzed with a computerized test battery for Speech Perception Tests in silence and in noise background to assess speech perception disabilities. In addition, with a test battery of Speech Perception Tests, we compared patients with migraines and tension-type headaches. The non-parametric χ2 test, the Mann-Whitney U-test and the Wilcoxon signed ranks test were used for statistical analysis. P-values <0.05 were considered significant and STATA 10 software was used for statistical analyses. RESULTS Our results showed that patients with primary headache (migraine and tension-type headache), had a deficit of auditory processing in noisy background compared to control cases, but we found no significant differences when we compared patients with migraine and tension-type headache. CONCLUSIONS This is a work in progress and further studies are needed to assess the relationship between the impairment of auditory processing and primary headache, not only to improve the diagnostic approach to primary headache, but also to improve therapeutic intervention.
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Affiliation(s)
- Antonella Ciriaco
- Headache and Drug Abuse Inter-Dep Research Centre, University of Modena and Reggio Emilia, via del Pozzo 71, Modena, Italy
| | - Angelo Russo
- Child Neurology and Psychiatry Unit, University of Modena and Reggio Emilia, via del Pozzo 71, 41124 Modena, Italy
| | - Daniele Monzani
- Audiology Unit, Department of Diagnostic Medicine, Clinical and Public Health, University of Modena and Reggio Emilia, via del Pozzo 71, Modena, Italy
| | - Elisabetta Genovese
- Audiology Unit, Department of Diagnostic Medicine, Clinical and Public Health, University of Modena and Reggio Emilia, via del Pozzo 71, Modena, Italy
| | - Paola Benincasa
- Otolaryngology Department, Hospital of Carpi, Via Guido Molinari 2, Carpi, Italy
| | - Ernesto Caffo
- Child Neurology and Psychiatry Unit, University of Modena and Reggio Emilia, via del Pozzo 71, 41124 Modena, Italy
| | - Luigi Alberto Pini
- Headache and Drug Abuse Inter-Dep Research Centre, University of Modena and Reggio Emilia, via del Pozzo 71, Modena, Italy
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Butterworth B, Kovas Y. Understanding Neurocognitive Developmental Disorders Can Improve Education for All. Science 2013; 340:300-5. [PMID: 23599478 DOI: 10.1126/science.1231022] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Brian Butterworth
- Institute of Cognitive Neuroscience, University College London, Alexandra House, 17 Queen Square, London WC1N 3AR, UK.
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Susilo T, Duchaine B. Advances in developmental prosopagnosia research. Curr Opin Neurobiol 2013; 23:423-9. [PMID: 23391526 DOI: 10.1016/j.conb.2012.12.011] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 12/31/2012] [Indexed: 10/27/2022]
Abstract
Developmental prosopagnosia (DP) refers to face recognition deficits in the absence of brain damage. DP affects ∼2% of the population, and it often runs in families. DP studies have made considerable progress in identifying the cognitive and neural characteristics of the disorder. A key challenge is to develop a valid taxonomy of DP that will facilitate many aspects of research.
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Affiliation(s)
- Tirta Susilo
- Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH 03755, USA.
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