Anna Maria Chilosi

Plasticity and Reorganization During Language Development in Children with Early Brain Injury

Although some studies have reported subtle language deficits following early focal brain lesions (EFBL), most studies find no evidence for differential language outcomes as a function of lesion side or lesion type in children with congenital injuries to one side of the brain. However, recent prospective studies of the first stages of language development in English-speaking children with EFBL have reported greater delays in expressive vocabulary in children with left-hemisphere damage, particularly if the lesion involves left temporal cortex. In the present study, first stages in the development of word production were studied in 43 Italian children with congenital EFBL, between 13 and 46 months of age. As a group, the EFBL children were markedly delayed in expressive vocabulary. Among children who were in the first stage of language learning, delays were significantly greater with left-hemisphere injury. However, this left-right difference was not evident in children who had moved on to the next stage of language development, producing at least some sentences. Discussion centers on the role of developmental plasticity in determining the outcomes of early focal brain injury, suggesting that recovery from initial delays may take place in the early stages of language development, at least for some children.

Cochlear implantation in deaf children with associated disabilities: Challenges and outcomes

The issue of cochlear implantation in deaf children with associated disabilities is an emerging subject. Currently, there is no consensus on whether to implant children with multiple impairments; moreover, it may be difficult to evaluate these children with standard tests pre- or post-implantation. In addition, these children often have poor speech perception and language skills, making assessment more difficult. Despite these factors, these children often receive important benefits in daily life, with an overall improvement in quality of life. In the present study, post-implant outcomes of 23 profoundly deaf children with neuropsychiatric disorders were analysed, using objective measures of speech perception, and a questionnaire administered to the parents, aimed at evaluating the benefits in daily life after implantation. The results were quite variable, but overall positive, in terms of speech perception, communication abilities, and improvement in quality of life. The findings add an additional piece of evidence to support the effectiveness of cochlear implantation in these special cases.

Rapid naming, not cancellation speed or articulation rate, predicts reading in an orthographically regular language (Italian)

This study examined the influence of rapid automatization naming (RAN) measures on various parameters of reading performance in children who were native speakers of a language with a shallow orthography (Italian). Participants included 281 children enrolled in first-to-sixth grade. They were given a Naming test, in which they had to name rapidly matrices of colors, objects, or digits, a Cancellation test, using the same stimulus materials, and an oral Articulation test. Performance on all tests improved steadily across ages tested. Performance on the Naming test, but not on the Cancellation and Articulation tests, predicted speed and accuracy in reading; none of these measures reliably predicted the reading comprehension measure. Data on a Blending test were also available for a subsample of first- and third-graders. Both RAN and phonological ability contributed independently to the prediction of reading ability (accuracy and speed) in these participants. The results extend observations on RAN to an orthographically shallow language (Italian) and suggest an element of continuity between languages with opaque and transparent orthographies.

Do phonologic and rapid automatized naming deficits differentially affect dyslexic children with and without a history of language delay? A study of Italian dyslexic children.

ObjectiveThe study aims to verify whether phonologic and rapid automatized naming (RAN) deficits are present and associated in Italian dyslexic children and whether they differentially affect dyslexics with and without a history of previous language delay (LD). BackgroundAccording to the phonologic core deficit hypothesis, dyslexia may stem from impairment of the representation and manipulation of phonemes and may be closely associated with oral language deficits. However, deficits in tasks not requiring fine-grained phonologic representations, such as RAN, have also been described in dyslexic children. MethodsThirty-seven children were selected on the basis of a reading deficit and were assigned to 2 groups according to whether or not they had a history of early LD as determined retrospectively by parental report. A battery of reading and writing, verbal working memory, metaphonologic, RAN, and visual search tests were administered. ResultsRAN deficits were shared by most dyslexics (with and without a history of LD), whereas phonologic deficits were mainly associated with a previous LD. This last condition did not result in a more profound impairment of reading and writing decoding skills. ConclusionIn a shallow orthography such as Italian, RAN, not phonologic deficits, may represent the main cognitive marker of developmental dyslexia.

Early Cognitive and Communication Development in Children With Focal Brain Lesions

Early cognitive and language development of children with congenital focal brain lesions, documented by magnetic resonance imaging, was studied in 18 cases, 9 with left-hemisphere damage and 9 with right-hemisphere damage, at about 2 (Time 1) and 4 years of age (Time 2). All of the children showed normal cognitive development, but their global Griffiths Developmental Scales scores were lower at Time 2, and developmental profiles across individual subscales revealed side-specific effects, resembling the adult left/right cerebral hemisphere lesion model. Expressive lexicon and grammar were delayed, more often in left-hemisphere-damaged than in right-hemisphere-damaged children, at Time 1 and Time 2. Functional findings were not related to the size and location of the brain lesion, whereas the presence of epilepsy was a highly significant predictor of cognitive and language outcome, irrespective of the side of the lesion. The stable disadvantage in the verbal domain shown by left-hemisphere-damaged children within the age range of this study might suggest that the left hemisphere has some initial bias for language learning. The effects of right-hemisphere damage were more variable and emerged at a later stage of language development. (J Child Neurol 2001;16:309-316).

Atypical language lateralization and early linguistic development in children with focal brain lesions.

The effects of congenital, unilateral, focal brain lesions on early linguistic development and hemispheric lateralization for language were investigated longitudinally in 24 preschool children with hemiplegia (14 males, 10 females), 12 with left hemisphere damage (LHD) and 12 with right hemisphere damage (RHD). A comprehensive linguistic assessment was performed at 2 and 3 years of life; cerebral lateralization for language was measured by the Fused Dichotic Words Listening Test. An early left-side specificity for language was indicated by the presence of lexical and grammatical delay in most children with LHD. In the dichotic listening test all 12 children with LHD showed a shift of language lateralization from the left to the right hemisphere. Atypical lateralization coefficients (lambda), i.e. values falling more than two standard deviations from the mean of a normative sample, were associated with a delay in lexical and grammatical development, especially after LHD. In addition, cortical-subcortical-periventricular lesions rather than solely periventricular damage, and larger lesions rather than small, were associated with the most atypical lateralization coefficients, irrespective of lesion side. Results of this study suggest that language and lateralization data are closely related and that reallocation of language functions in alternative regions of the brain has a cost in terms of a slow rate of language acquisition.

Treatment with l-Arginine improves neuropsychological disorders in a child with Creatine transporter defect

Creatine transporter deficit (CT1) is an inherited metabolic disorder that causes mental retardation, epilepsy, speech, language and behavioral deficits. Until now, no treatment has been proven to be successful for this condition. We describe 1-year follow-up study of a child, aged 9.6 years, with CT1 defect, on oral supplementation with l-arginine, a precursor of creatine synthesis. Under supplementation, he showed a noticeable improvement of neurological, language and behavioral status and an increase of brain creatine and phosphocreatine documented with magnetic resonance spectroscopy. The results suggest that children with CT1 disorder show some residual adaptive plasticity for certain functions even at quite an advanced age. Further trials with higher l-arginine dosages and more protracted treatment are encouraged.

Language organisation in left perinatal stroke.

Right-hemispheric organisation of language has been observed following early left-sided brain lesions. The role of the site of damage is still controversial, as other aspects influence the pattern of speech organisation including timing of the lesion and the presence of epilepsy. We studied a group of 10 term-born children homogeneous for timing/type of lesion and clinical picture. All subjects had left perinatal arterial stroke, right hemiplegia, normal cognitive functions and no or easily controlled epileptic seizures. In half the patients, the lesion clearly involved Brocas area, in the other half it was remote from it. Language lateralization was explored by an fMRI covert rhyme generation task. Eight of 10 subjects showed a right lateralisation of language, including all five patients with a damaged left Broca and 3/5 of those without it. Group analysis in patients with right hemispheric organisation showed brain activations homotopic to those found in the left hemisphere of a matched control group. Our findings confirm that, at the end of gestation, the human brain exhibits extraordinary (re-)organisational capabilities. Language organisation in the right hemisphere is favoured by the presence of destructive lesions of the left Brocas area at birth, and occurs in brain regions homotopic to those usually involved in language processing.

Neurodevelopmental disorders in children with severe to profound sensorineural hearing loss: a clinical study

Aim  The effects of sensorineural hearing loss (SNHL) are often complicated by additional disabilities, but the epidemiology of associated disorders is not clearly defined. The aim of this study was to evaluate the frequency and type of additional neurodevelopmental disabilities in a sample of children with SNHL and to investigate the relation between these additional disabilities and the aetiology of deafness.

Acquired focal brain lesions in childhood: Effects on development and reorganization of language

In the present paper, we address brain-behaviour relationships in children with acquired aphasia, by reviewing some recent studies on the effects of focal brain lesions on language development. Timing of the lesion, in terms of its occurrence, before or after the onset of speech and language acquisition, may be a major factor determining language outcome. However, it is still unclear which are the effects of aphasia occurring between 2 and 5 years of age, a time window which is crucial for acquiring and automatizing the basic rules of native language. A comprehensive review of the literature on acquired childhood aphasia precedes the description of long-term follow-up (20 years) of two identical twins, one of whom became aphasic at 3 years and 4 months after infarction of the left sylvian artery. Psycholinguistic analysis and fMRI data show a slow and incomplete recovery from non-fluent aphasia associated to an intra-hemispheric organization of language. These data, which support the potential but also the limits of neural plasticity during language development, are discussed in the light of the literature on the time-course and neural bases of acquired childhood aphasia.