A comparison of audiometric and objective methods in hearing screening of school children. A preliminary study.

OBJECTIVE: In newborn hearing screening, one exclusively applies objective hearing testing methods--based on evoked potentials and/or on otoacoustic emissions. However, when testing school children, one can consider both audiometric and electrophysiological methods. The choice of methods is determined by the aims of the program. If one wants to detect conductive hearing losses, impedance audiometry seems to be the method of choice. METHODS: The aim of this study was to compare test performance measures from audiometric and objective methods (OAEs and impedance audiometry), in the hearing screening of school children. Screening protocols were applied on a group of 190 children of about 12 years of age (6th grade of primary school). RESULTS: For a single application of a screening procedure, the best performance was observed in the automated four-tone audiometry, followed by the tympanometry and the TEOAE-based procedures. Screening performance was enhanced using a combination of automated and impedance audiometry. A four-tone audiometry test combined with tympanometry gives a sensitivity of 65%, and the PPV of 46%, which are reasonable values, acceptable for practical use. The use of a TEOAE protocol degrades the overall performance of screening. CONCLUSIONS: Screening of school children is feasible with a combination of automated audiometry and tympanometry with time requirements equal to 3 min per subject.

[Event-related potentials - an objective tool for assessment of the speech understanding process. II. Syntactic potentials (ELAN, P600)].

Investigations into electrophysiological potentials reflecting the process of grammatical analysis of the speech structure revealed a positive wave with the latency of 600 ms and maximum amplitude within the parietal region (P 600 wave). Presumably, this wave can reflect some consciously controlled processes of re-analysis and correction of grammatical and syntactic inconsistencies. It can be used for the diagnosis of speech disorders.

Deficits of non-verbal auditory perception in postlingually deaf humans using cochlear implants.

Temporal integration in the time domain of a few seconds was investigated with a subjective accentuation paradigm in 11 monochannel cochlear implant users, who showed auditory comprehension deficits. While listening to metronome beats generated at various frequencies, patients were asked to accentuate mentally every n-th beat and create an individual rhythmic pattern. The extent of temporal integration was defined as the duration of perceptual units consisting of subjectively grouped beats at particular metronome frequencies. The results indicate that there is reduced capacity for temporal integration in implant recipients, particularly for lower metronome frequencies, in comparison to normally hearing. These observations point to the coincidence of specific temporal processing disorders and deficits in auditory comprehension after cochlear implantation.