B Maassen — Page 2 | PubMed Health

PubMed1984

The effect of correcting fundamental frequency on the intelligibility of deaf speech and its interaction with temporal aspects.

This study investigates the role of intonation for the intelligibility of deaf speech. The intonation contours of Dutch sentences spoken by deaf children were manipulated using digital signal processing techniques, including LPC analysis. Sentence intonation was corrected by replacing the original F0 contour of the deaf utterance with an artificial contour derived from a formalized intonation grammar. Three types of intonation corrections were produced, differing with respect to the underlying accent structure and the type of F0 movements used. The overall results show that intonation correction yields a small but significant improvement in intelligibility of 7% (from 20% to 27% words correctly identified). The largest gain is obtained after removal of over-accentuations. To evaluate the interaction with temporal aspects, intonation corrections were also implemented on temporally corrected sentences. Total growth in intelligibility due to these combined corrections amounts to 13%. Thus it is concluded that no dramatic gain in intelligibility may be expected if speech pathologists succeed in teaching their deaf pupils to have better control over the suprasegmental aspects of their speech.

Adolescent↗

PubMedDate not supplied

Detectability of auditory evoked response components in preterm infants.

In determining the detectability of brainstem, middle latency and cortical auditory evoked responses in preterm newborns, one has to deal with the ongoing maturation of the auditory system. In the preterm period the detectability of evoked responses is closely related to the appearance of the individual evoked response components. The detectability of the individual evoked response components in preterm infants is important, because low detectability rates make the absence of a particular evoked response component irrelevant with respect to the clinical-neurophysiological correlation. In a longitudinal study we determined the detectability and cumulative detectability, i.e. the presence of individual evoked response components in one or more recordings of evoked response components in 37 low risk preterm infants between 30 and 41 weeks conceptional age (CA). On the basis of their detectability it is concluded that evoked response components, determined between 30 and 34 weeks CA, are generally of limited use for clinical application, except for auditory brainstem response (ABR) components I, IIn, V and Vc and middle latency response (MLR) component Na. Our study made clear that improvement can be achieved by performing more than one examination within a period of approximately 4 weeks between the recording sessions. The cumulative detectability rates after two recordings showed improvement for all components involved in this study. The cumulative detectability rates of ABR components I, II, IIN, III, V, IIc, IIINc, Vc, MLR components Na and P0, and auditory cortical response (ACR) components PbP1 and N2p are sufficient to use as measures in the neurophysiological judgement of functional integrity of the central auditory pathway in preterm infants.

Auditory Cortex↗