A comparison between linguistic skills and socio-communicative abilities in Williams syndrome.

BACKGROUND: Individuals with Williams syndrome (WS) show a disharmonic linguistic profile with a clear pattern of strengths and weaknesses. Despite their sociable nature, atypical socio-communicative abilities and deficits in communication and relationship with others have been found. AIM: The aim of the present study was to investigate whether linguistic skills (LS) were in line with the pragmatic and social use of language and the cognitive development of 32 individuals with WS (18 boys and 14 girls) with a mean chronological age of 12.3 (±4.4) years. To examine the relationship between language and mental age (MA) at different ages, the issue was investigated in children and adolescents/young adults with WS. METHOD: Measures of LS, including lexical and morphosyntactic competences, and adaptive socio-communicative abilities (ASCA), pertaining to the use of language in daily living social context, were compared with the MA of participants. In a second step, participants with WS were split into two subgroups based on age, and the relationship between LS, ASCA and MA was studied. RESULTS: Although expressive and receptive LS were generally found to be in line with or better than would be expected for MA, specific deficits in receptive ASCA were documented. LS and ASCA appeared to have a different evolution during the different time windows considered. CONCLUSIONS: Our results underlined the importance of assessing linguistic abilities in the context of adaptive functioning, to guide educational and rehabilitative strategies for individuals with WS.

Do children with developmental dyslexia have an implicit learning deficit?

OBJECTIVE: The purpose of this study was to investigate the effects of specific types of tasks on the efficiency of implicit procedural learning in the presence of developmental dyslexia (DD). METHODS: Sixteen children with DD (mean (SD) age 11.6 (1.4) years) and 16 matched normal reader controls (mean age 11.4 (1.9) years) were administered two tests (the Serial Reaction Time test and the Mirror Drawing test) in which implicit knowledge was gradually acquired across multiple trials. Although both tests analyse implicit learning abilities, they tap different competencies. The Serial Reaction Time test requires the development of sequential learning and little (if any) procedural learning, whereas the Mirror Drawing test involves fast and repetitive processing of visuospatial stimuli but no acquisition of sequences. RESULTS: The children with DD were impaired on both implicit learning tasks, suggesting that the learning deficit observed in dyslexia does not depend on the material to be learned (with or without motor sequence of response action) but on the implicit nature of the learning that characterises the tasks. CONCLUSION: Individuals with DD have impaired implicit procedural learning.

Verbal short-term memory in Down's syndrome: an articulatory loop deficit?

BACKGROUND: Verbal short-term memory, as measured by digit or word span, is generally impaired in individuals with Down's syndrome (DS) compared to mental age-matched controls. Moving from the working memory model, the present authors investigated the hypothesis that impairment in some of the articulatory loop sub-components is at the base of the deficient maintenance and recall of phonological representations in individuals with DS. METHODS: Two experiments were carried out in a group of adolescents with DS and in typically developing children matched for mental age. In the first experiment, the authors explored the reliance of these subjects on the subvocal rehearsal mechanism during a word-span task and the effects produced by varying the frequency of occurrence of the words on the extension of the word span. In the second experiment, they investigated the functioning of the phonological store component of the articulatory loop in more detail. RESULTS: A reduced verbal span in DS was confirmed. Neither individuals with DS nor controls engaged in spontaneous subvocal rehearsal. Moreover, the data provide little support for defective functioning of the phonological store in DS. CONCLUSIONS: No evidence was found suggesting that a dysfunction of the articulatory loop and lexical-semantic competence significantly contributed to verbal span reduction in subjects with DS. Alternative explanations of defective verbal short-term memory in DS, such as a central executive system impairment, must be considered.

A multifunctional, provisional, implant-retained fixed partial denture.

This article describes the modification of a procedure for fabricating a laboratory-processed, metal-reinforced, acrylic resin provisional restoration that becomes an implant-retained fixed partial denture. The modification involves the incorporation of patrix and matrix components into a cast metal framework. The prosthesis can be used as an alternative to a removable radiologic stent and surgical guide. It can function as a surgical guide during implant placement and help retract the buccal mucogingival flap during implant placement. The prosthesis also can be used as an aid in locating the implant during stage II surgery. Finally, the pontics can be converted into an implant-supported provisional restoration immediately after the implant prosthetic components are attached to the uncovered implants.

Word-list learning in normally developing children: effects of semantic organization and retention interval.

Immediate and 15-min delayed recall of semantically related or unrelated word lists was investigated in 144 normally developing children ranging from 5 to 10 years of age. Immediate recall for the related and unrelated lists increased in a parallel fashion as a function of age. The ability to cluster semantically related items during immediate recall also improved with age. However, in no age class recall scores and clustering indexes were significantly associated. Forgetting rate passing from the last immediate to the delayed recall trial increased for the unrelated list but decreased for the related list of words as a function of age. Results of regression analyses revealed that a developmental increase in forgetting on the unrelated list was actually due to the higher number of words recalled in the last immediate trial by older children. As for the related list, instead, the larger reliance on the clustering strategy of recall by older children was responsible for the progressive reduction of forgetting.

Long-term memory in mental retardation: evidence for a specific impairment in subjects with Down's syndrome.

This study aimed at investigating long-term memory functioning in Down's syndrome subjects (DS) as compared to individuals with mental retardation of different etiology (MR) and mental-age matched normal children (MA). For this purpose, tests of verbal and visuo-perceptual explicit memory and a verbal repetition priming task were administered to 15 DS, 15 MR and 30 MA subjects. Our results document comparable verbal priming in the three groups. As for explicit memory, normal children performed better than MR individuals, and these, in turn, better than DS subjects. Compared to MR subjects, DS subjects were particularly deficient in organizing verbal material according to its categorical structure and in actively retrieving stored information. These results support a view positing heterogeneity of neuropsychological deficits across distinct etiology MR groups.

[Incidence of wheezing asthma, rhinitis, urticaria and conjunctivitis in a pediatric emergency department]. / L'incidenza di wheezing-asma, tosse, rinite, orticaria, congiuntiviti in un dipartimento di emergenza pediatrica.

The Authors considered the incidences of the urgencies for allergic pathology arrived at Santobon Hospital during January-December 1992. In the period of twelve months a whole of 42.702 children came to Hospital; among them 4.359 showed an allergic pathology with a clear prevalence for wheezing and asthma. In addition it was observed too that an allergic mainly affected male children.

Neurotransmitter-related markers in the normal and experimentally lesioned telencephalon of the goldfish.

The telencephalon of teleost fish shows high affinity uptake for D-[3H]aspartate, intermediate levels of GABAergic markers and low levels of cholinergic enzymes. Experimental results (resection of the olfactory tracts or unilateral kainic acid administration in the telencephalon) suggest that: the projection from the olfactory bulbs to telencephalic targets is mediated by aspartate and/or glutamate; and a population of GABAergic neurons is present in a telencephalic area which is considered homologous to part of the striatal complex of land vertebrates. From the present results, it appears that the neurochemical approach can be used, in conjunction with neuroanatomical methods, to study evolutionary problems of telencephalic function.

Radio frequency glow discharge and solid-phase lactoperoxidase-glucose oxidase beads as methods for etching ultra-thin plastic sections for immunoelectron microscopy.

Etching techniques to prepare ultra-thin sections for immunoelectron microscopy have incorporated a variety of reagents to expose antigenic sites. In this paper involving 2 techniques for surface etching prior to immunoelectron microscopy, radio frequency glow discharge ( RFGD ) and solid-phase lactoperoxidase-glucose oxidase beads ( Enzymobeads ) are compared to conventional peroxide etching techniques. Measuring such parameters as intensity of granule disposition and titers of antibody resulting in detectable staining. RFGD and Enzymobeads were both superior to the conventional peroxide methodology. Non-specific absorption by ferritin under the conditions utilized was not a problem with Enzymobeads or RFGD method. In addition, RFGD may be useful in situations where peroxide susceptible antigens are under study.