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Increase in the auditory abilities of children with cochlear implants (CIs) has led to an improvement in naming tasks, although divergent results are still being reported; this strongly suggests that further studies are needed. The study aims to compare the responses in a picture-naming activity between the complete population of children aged 5 to 7 with cochlear implants in Catalonia -Spain- (N = 31), without developmental problems, and a matched sample of 31 children with typical hearing. A picture-naming task was used to assess their lexical naming abilities. The results show that children with CIs provide more non-responses, they produce fewer words correctly, they require a longer reaction time and they commit more picture-naming errors than children with typical hearing. The auditory age does significantly affect the results, but not the type of implant. In spite of the hearing gain achieved with the cochlear implant and the listening experience progressively achieved in distinct contexts, further explicit work on lexical naming in speech-therapy intervention is clearly required.

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BACKGROUND: The rapid development of language abilities in early childhood coincides with a similarly accelerated progression in brain maturation. OBJECTIVE: To quantitate myelination in the lateral part of the verbal left hemisphere from birth to 3 years in the living human brain. METHODS: One hundred children (mean age 16.6 months) were examined using three-dimensional MRI, and a subgroup of 40 children were also evaluated behaviorally. The volume of myelinated white matter was measured in language-related temporal and frontal regions and in the central sensorimotor region. A method was developed to compose a movie sequence for all the myelination process using volumetric data. RESULTS: A plot of age against relative volume of myelinated white matter graphically detailed the myelination progress in the lateral brain. The changes started in sensorimotor white matter and the Heschl gyrus and ultimately extended to the language-related areas. Both comprehension and production regions showed a very similar myelination course, suggesting simultaneous maturation of the temporofrontal language network. The movie sequence of white matter images dynamically displayed the anatomic details of myelin deposition in this part of the brain. The analysis of language performance showed acceleration in children's vocabulary after 18 months, once a rapid myelination phase was attained in the language brain. CONCLUSIONS: This volumetric study may contribute to further characterize the early stages of brain maturation by showing the fine progression of myelin deposition in the language domains and illustrating its relationship to children's vocabulary acquisition.

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OBJECTIVE: To use functional MRI (fMRI) to further define the occurrence of left-hemisphere, bilateral, and right-hemisphere language in a normal left-handed population. METHODS: A total of 100 healthy volunteers, consisting of 50 left-handed subjects and a reference group of 50 right-handed subjects, were studied by fMRI of the frontal cortex during silent word generation. RESULTS: Ninety-six percent of right-handed subjects showed fMRI changes lateralized to the left hemisphere, whereas 4% showed a bilateral activation pattern. In contrast, left-hemisphere lateralization occurred in 76% of left-handers, bilateral activation in 14%, and right-hemisphere lateralization in the remaining 10%. The predominance of right-hemisphere activation, however, was weak in these cases; only a single left-handed subject (2%) showed complete right-hemisphere lateralization. CONCLUSIONS: Silent word generation lateralizes to the left cerebral hemisphere in both handedness groups, but right-hemisphere participation is frequent in normal left-handed subjects. Exclusive right-hemisphere activation rarely occurred in the frontal lobe region studied.

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The paper examines the diagnostic agreement between clinicians and the Diagnostic Interview for Children and Adolescents. One hundred and thirty-seven outpatients-children and adolescents, and their parents-were diagnosed independently following DSM-III-R criteria by clinicians and by the DICA-R. The diagnostic concordance between clinicians and DICA-R ranged from low to moderate in the majority of the categories. The only exception was Conduct Disorder. Differences depending on the informant and the quality of the information (cognitive vs. observable) were observed. Combining the information from the child/adolescent and their parents ameliorates the concordance. The reasons for the scanty agreement found could be due to the fact that clinicians and structured interviews differ in what they evaluate (conditions on which they focus), how they evaluate (strictness in the criteria application, use of different informants and different information etc.), and when they evaluate (present condition vs. lifespan). After analysing the pros and cons of both, the use of structured interviews is advisable for research purposes. There is a clear need for a variety of informants, and the combination of information from different sources is recommended, depending on the age of the children and the type of disorder.

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