Right cerebral hemisphere and central auditory processing in children with developmental dyslexia

Abstract

Objective We hypothesized that if the right hemisphere auditory processing abilities can be altered in children with developmental dyslexia (DD), we can detect dysfunction using specific tests. Method We performed an analytical comparative cross-sectional study. We studied 20 right-handed children with DD and 20 healthy right-handed control subjects (CS). Children in both groups were age, gender, and school-grade matched. Focusing on the right hemisphere’s contribution, we utilized tests to measure alterations in central auditory processing (CAP), such as determination of frequency patterns; sound duration; music pitch recognition; and identification of environmental sounds. We compared results among the two groups. Results Children with DD showed lower performance than CS in all CAP subtests, including those that preferentially engaged the cerebral right hemisphere. Conclusion Our data suggests a significant contribution of the right hemisphere in alterations of CAP in children with DD. Thus, right hemisphere CAP must be considered for examination and rehabilitation of children with DD.

Sound localization and word discrimination in reverberant environment in children with developmental dyslexia

“…Alteration for sound localization found at -45 o may results from right Parietal lobe dysfunction, as suggested from data from other researchers 23,24 . Difficulties for localization were also found in positive angles which suggests a link with a left-hemisphere temporo-parietal alteration 25,26 .…”

“…This was one of the most significant finding of our research, to show the increased difficulties of children with DD, when they have to face a task, that challenge a higher order perceptual network, with a predominance of participation of the neurons decoding stimuli in right cerebral hemisphere. In one study carried-out by Murphy-Ruiz et al, authors observed that although all psychoacoustics tests engaged both cerebral hemispheres, some abnormal tests were linked to right hemisphere processing 24 . Ligges et al observed by means of fMRI and electroencephalography that children with DD used the right-hemisphere analogues areas to the posterior left-hemisphere language areas, to compensate the processing deficits 31 .…”

Processamento auditivo central e processos de leitura em crianças e adolescentes: revisão integrativa

“…In other words, these studies were carried out with children regularly enrolled in educational institutions (19)(20)(21)23,24) , or with children suspected of central auditory processing disorder (22) . The other studies compared 2 (26)(27)(28)(29)(30)(31)(32)34,(36)(37)(38)(39)(40)(41)(42)(43)45,49,51,(54)(55)(56)(57)(58)61) , 3 (25,33,44,(46)(47)(48)50,52,53,59,60) or 5 (62) study groups. It was also found that in 4 studies (26,35,62,63) auditory training was carried out in groups with alterations: participants with reading difficulties (26) and with learning disorders (35...…”

“…Regarding the design of studies, it was observed that most of them presented cross-sectional designs (10,19,20,22,24,25,(27)(28)(29)(30)(31)(32)(33)(34)37,38,49), followed by studies with case-control designs (39,(43)(44)(45)50,51,(53)(54)(55)(56)(58)(59)(60)(61) .…”

Alterações de linguagem e processamento auditivo: revisão de literatura

“…Loo JHY, Bamiou DE, Campbell N et al (21) The study of Murphy-Ruiz, Penaloza-López et. al 12 showed that children with developmental dyslexia presented lower performance than children with typical development in all auditory processing tests. Such evidence corroborates the literature, as children with language disorders present alterations in the phonological processing related to an auditory processing disorder, in other words, children with dyslexia present changes in auditory skills 29 .…”