A Magnetic Resonance Imaging Study of Planum Temporale Asymmetry in Men With Developmental Dyslexia

Rumsey, Judith M.; Donohue, Brian C.; Brady, Daniel R.; Nace, Kristy; Giedd, Jay N.; Andreason, Paul

doi:10.1001/archneur.1997.00550240035010

Cited by 123 publications

(63 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Functional neuroimaging studies including PET and fMRI have also shown decreased physiological activation in similar regions to both phonological and non-linguistic transient auditory stimuli (e.g. Hagman et al, 1992;Paulesu et al, 1996;Rumsey et al, 1992Rumsey et al, , 1997Shaywitz et al, 1998;Temple et al, 2000). Identification and exploration of the possible etiology and developmental trajectory of such atypical brain organization is of much interest and could be examined within a prospective longitudinal study of infants.…”

Section: Discussionmentioning

confidence: 99%

The infant as a prelinguistic model for language learning impairments: Predicting from event-related potentials to behavior

et al. 2006

View full text Add to dashboard Cite

Associations between efficient processing of brief, rapidly presented, successive stimuli and language learning impairments (LLI) in older children and adults have been well documented. In this paper we examine the role that impaired rapid auditory processing (RAP) might play during early language acquisition. Using behavioral measures we have demonstrated that RAP abilities in infancy are critically linked to later language abilities for both non-speech and speech stimuli. Variance in infant RAP thresholds reliably predict language outcome at 3 years-of-age for infants at risk for LLI and control infants. We present data here describing patterns of electrocortical (EEG/ ERP) activation at 6 month-of-age to the same non-verbal stimuli used in our behavioral studies. Well-defined differences were seen between infants from families with a history of LLI (FH+) and FH− controls in the amplitude of the mismatch response (MMR) as well as the latency of the N 250 component in the 70 ms ISI condition only. Smaller mismatch responses and delayed onsets of the N 250 component were seen in the FH+ group. The latency differences in the N 250 component, but not the MMR amplitude variation, were significantly related to 24-month language outcome. Such converging tasks provide the opportunity to examine early precursors of LLI and allow the opportunity for earlier identification and intervention.

show abstract

Section: Discussionmentioning

confidence: 99%

The infant as a prelinguistic model for language learning impairments: Predicting from event-related potentials to behavior

et al. 2006

View full text Add to dashboard Cite

show abstract

“…Utilizando exames como a ressonância magnética vários autores encontraram em grupos de disléxicos ectopias e microgirias, entre outras alterações corticais em áreas importantes para a audição como a fissura peri-sylviana, áreas de associação do lobo temporal esquerdo, giro angular, giro supramarginal e córtex temporal posterior [21][22][23][24][25][26][27] . P e s t u n 3 re f e re que para a realização de uma leitura com compreensão adequada é necessária a integridade do sistema nervoso periférico e central, bem como certos pré-requisitos fundamentais como atenção seletiva e sustentada, discriminação e perc e p ç ã o auditiva, memória de curto e longo prazo e consciên-cia fonológica, habilidades essas avaliadas no conjunto de testes especiais do PA.…”

Section: Discussionunclassified

Processamento auditivo e SPECT em crianças com dislexia

Sauer

Pereira

Ciasca

et al. 2006

Arq. Neuro-Psiquiatr.

View full text Add to dashboard Cite

RESUMO -Aplicamos em um grupo de 36 crianças os testes dicótico de dígitos, dicótico de dissílabos altern ados e dicótico não-verbal, os quais fazem parte do conjunto de avaliação do processamento auditivo. As crianças foram divididas em dois grupos que foram correlacionados: grupo experimental (GE) formado por 18 crianças com diagnóstico de dislexia e 18 crianças normais compondo o grupo comparação (GC), sem queixa de aprendizagem e pareadas em relação a sexo, lateralidade e nível sócio-econômico ao GE. Realizamos o exame de imagem (SPECT) no GE. Encontramos em nosso estudo diferença estatisticamente significante e n t re os grupos (GE e GC) em todos os testes avaliados. Em relação ao SPECT, apesar de não encontrarm o s d i f e rença estatisticamente significante entre os resultados, pudemos observar que 50% dos sujeitos avaliados a p resentaram alteração, sendo a maior parte em áreas do lobo temporal esquerdo. Concluímos que crianças com dislexia apresentam alterações do processamento neurológico central que podem ser detectadas tanto em testes específicos de processamento auditivo, quanto em exames funcionais de imagem como SPECT.PALAVRAS-CHAVE: dislexia, processamento auditivo, neuroimagem, teste dicótico. Dichotic listening and SPECT in dyslexic childrenABSTRACT -Dichotic listening (DL) was evaluated in 36 children with: verbal dichotic listening test, altern a t i n g dissilable dichotic test and non-verbal dichotic listening test. Children were separated into two gro u p s : experimental group with 18 dyslexic children and control group with 18 normal children. Both groups were comparable in gender, laterality and social-economic level. All dyslexic children underwent neuro i m a g i n g exam (SPECT). Our data showed that there was a statistical diff e rence between both groups in all DL tests. A b n o rmal SPECT findings were seen in 50% of the dyslexic children, hypoperfusion of the left temporal lobe being the most frequent abnorm a l i t y. We conclude that dyslexic children present an impairment of central neurologic processing that may be detected by DL tests, and by functional imaging exam, such as SPECT, as well.KEY WORDS: dyslexia, imaging, dichotic listening test.Todos os animais se comunicam, mas só o homem é capaz de falar, ler e escre v e r. A leitura e escrita são as formas mais elevadas da linguagem, que exigem um processo linguístico anatômico e neuro p s i c o l ó g i c o altamente complexo. A dificuldade de apre n d i z a g e m para as habilidades de leitura e escrita são denominadas de dislexia do desenvolvimento ou, segundo o DMS-IV, transtorno de leitura, que pode também coexistir com dificuldades na linguagem oral, cálculo, atenção, memória e integração perc e p t i v o -m o t o r a 1 . A dislexia do desenvolvimento parece ser um distúr-bio neurológico congênito, acometendo estru t u r a s s u b c o rticais e cort i c a i s 1 , 2 . SPECT (Single Photon Emission Computed Tomography) é uma modalidade de imagem que permite avaliação funcional do cére b ro , ou seja, fornece informações ...

show abstract

“…Generalizing this finding Galaburda et al proposed that symmetrical brains of dyslexics result from a diminished neural loss in the right hemisphere during prenatal development. It deserves mention, however, that more recent MRI techniques have failed to find significant changes in normal planum temporale asymmetry in people with dyslexia [21,39,41]. Variations in subject characteristics (i.e.…”

Section: Introductionmentioning

confidence: 99%

Atypical organisation of the auditory cortex in dyslexia as revealed by MEG

et al. 2000

View full text Add to dashboard Cite

Neuroanatomical and -radiological studies have converged to suggest an atypical organisation in the temporal bank of the left-hemispheric Sylvian fissure for dyslexia. Against the background of this finding, we applied high temporal resolution magnetoencephalography (MEG) to investigate functional aspects of the left-hemispheric auditory cortex in 11 right-handed dyslexic children (aged 8-13 years) and nine matched normal subjects (aged 8 -14 years). Event-related field components during a passive oddball paradigm with pure tones and consonant -vowel syllables were evaluated. The first major peak of the auditory evoked response, the M80, showed identical topographical distributions in both groups. In contrast, the generating brain structures of the later M210 component were located more anterior to the earlier response in children with dyslexia only. Control children exhibited the expected activation of more posterior source locations of the component that appeared later in the processing stream. Since the group difference in the relative location of the M210 source seemed to be independent of stimulus category, it is concluded that dyslexics and normally literate children differ as to the organisation of their left-hemispheric auditory cortex.

show abstract

A Magnetic Resonance Imaging Study of Planum Temporale Asymmetry in Men With Developmental Dyslexia

Cited by 123 publications

References 53 publications

The infant as a prelinguistic model for language learning impairments: Predicting from event-related potentials to behavior

The infant as a prelinguistic model for language learning impairments: Predicting from event-related potentials to behavior

Processamento auditivo e SPECT em crianças com dislexia

Atypical organisation of the auditory cortex in dyslexia as revealed by MEG

Contact Info

Product

Resources

About