Cochlear implant performance in a deaf child of deaf parents: a case study.

Marie represents a unique case in the population of cochlear implant users, in that she is from a family of deaf individuals. Her auditory perceptual performance after 2 years of implant use is commensurate with that of other children of similar ages and durations of deafness. Although her speech production performance is also not atypical, the special circumstances in the home might cause additional delay. Studies have traditionally shown that deaf children of deaf adults exhibit superior ability in both social and academic domains when compared to deaf children of hearing parents. The cochlear implant provides yet another tool to add to the already-identified advantage extended this group by their family circumstance. It is unfortunate that these children for whom the device can offer enhanced abilities may be the very children that are denied access to it by the deaf community.

The development of a Children's Implant Profile.

The decision to provide a child with a cochlear implant is quite complex, as it must include consideration not only of the implant itself but also of the habilitative services necessary following the surgical procedure. To provide a systematic means of selecting hearing-impaired children for cochlear implants, a team at Children's Hearing Institute, Manhattan Eye, Ear and Throat Hospital, developed the Children's Implant Profile (ChIP). There is no one profile of a successful implant user--at least 11 factors appear to contribute to successful implantation. In the ChIP, each factor is evaluated on a three-point scale: (1) no concern, (2) mild-to-moderate concern, and (3) great concern. A profile showing "no concern" on all 11 factors denotes clear acceptability of the child as an implant candidate. A profile including several ratings in the "mild-to-moderate concern" category suggests a need for further study to determine if improvements could be made in projected outcomes before initiating surgical procedures. Finally, ratings of "great concern," especially on more than one factor, indicate a very limited probability of successful implant outcomes, at least at the time of evaluation. A case study is presented to demonstrate the relationship between the evaluated factors and to show how the profile is used to address and remedy areas of concern.

Methylcitric acid determination in amniotic fluid by electron-impact mass fragmentography.

Methylcitric acid, a metabolite of abnormal propionyl-CoA metabolism, is elevated in amniotic fluid when the fetus is affected with propionic acidaemia or methylmalonic aciduria. We developed a method for quantifying methylcitric acid in amniotic fluid by solid-phase extraction, derivatisation to the t-butyl-dimethylsilylester, and gas chromatography-mass spectrometry with electron-impact ionisation, using the deuterated analogue of methylcitric acid as an internal standard. The main advantages are a good sensitivity, simple sample preparation, and feasibility on instruments equipped with mass specific detectors.

The instantiation of general terms by deaf adolescents/adults.

Two studies were conducted using severely and profoundly deaf high school students to determine their ability to instantiate particular exemplars of general nouns and to use those instantiations as retrieval cues. The results indicated that the deaf adolescents/adults could instantiate when asked to do so but did not do so spontaneously; sentence recall was best when the retrieval cue matched the word used in the original sentence; and recall of sentences in which all information was explicit was better than of sentences in which some information had to be inferred. Impoverished semantic representations, difficulty in integrating semantic representations, and insufficient strategy use were suggested as possible alternative and competing explanations for the obtained results.