[Show abstract][Hide abstract] ABSTRACT: This report describes relationships between middle-ear measurements of acoustic admittance and energy reflectance (YR) and measurements of hearing status using visual reinforcement audiometry in a neonatal hearing-screening population. Analyses were performed on 2638 ears in which combined measurements were obtained [Norton et al., Ear Hear. 21, 348-356 (2000)]. The measurements included distortion-product otoacoustic emissions (DPOAE), transient evoked otoacoustic emissions (TEOAE), and auditory brainstem responses (ABR). Models to predict hearing status using DPOAEs, TEOAEs, or ABRs were each improved by the addition of the YR factors as interactions, in which factors were calculated using factor loadings from Keefe et al. [J. Acoust. Soc. Am. 113, 389-406 (2003)]. This result suggests that information on middle-ear status improves the ability to predict hearing status. The YR factors were used to construct a middle-ear dysfunction test on 1027 normal-hearing ears in which DPOAE and TEOAE responses were either both present or both absent, the latter condition being viewed as indicative of middle-ear dysfunction. The middle-ear dysfunction test classified these ears with a nonparametric area (A) under the relative operating characteristic curve of A = 0.86, and classified normal-hearing ears that failed two-stage hearing-screening tests with areas A = 0.84 for DPOAE/ABR, and A = 0.81 for TEOAE/ABR tests. The middle-ear dysfunction test adequately generalized to a new sample population (A = 0.82).
The Journal of the Acoustical Society of America 02/2003; 113(1):407-22. DOI:10.1121/1.1523388 · 1.50 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This report describes the extent to which ear-canal acoustic admittance and energy reflectance (YR) in human neonates (1) predict otoacoustic emission (OAE) levels and auditory brainstem response (ABR) latencies, and (2) classify OAE and ABR responses as present or absent. Analyses are reported on a subset of ears in which hearing screening measurements were obtained previously [Norton et al., Ear. Hear. 21, 348-356 (2000a)]. Tests on 1405 ears included YR, distortion-product OAEs, transient-evoked OAEs, and ABR. Principal components analysis reduced the 33 YR variables to 5-7 factors. OAE levels decreased and ABR latencies increased with increasing high-frequency energy reflectance. Up to 28% of the variance in OAE levels and 12% of the variance in ABR wave-V latencies were explained by these factors. Thus, the YR response indirectly encodes information on inter-ear variations in forward and reverse middle-ear transmission. The YR factors classify OAEs with an area under the relative operating characteristic (ROC) curve as high as 0.79, suggesting that middle-ear dysfunction is partly responsible for the inability to record OAEs in some ears. The YR factors classified ABR responses less well, with ROC areas of 0.64 for predicting wave-V latency and 0.56 for predicting Fsp.
The Journal of the Acoustical Society of America 02/2003; 113(1):389-406. DOI:10.1121/1.1523387 · 1.50 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A stimulus frequency otoacoustic emission (SFOAE) is a cochlear‐based signal measured in the ear canal in response to sine‐tone stimulation. SFOAE responses are potentially related to other auditory‐system responses to sine‐tone stimulation, e.g., basilar membrane input/output (I/O) functions, and behavioral studies of nonlinearity. In preliminary experiments, system distortion has been measured in an ear simulator using SFOAE and DPOAE paradigms, and different probes. SFOAE I/O functions have been measured in subjects using the double‐evoked method [D. H. Keefe, J. Acoust. Soc. Am. 103, 3489–3498 (1998)] in two approaches: equal‐level stimuli in each loudspeaker, or a fixed high level in one loudspeaker and varying level in the other. The latter approach is particularly helpful, because it controls for mutual suppression effects in SFOAE responses. Based on the use of transient‐gated stimuli, time‐frequency representations of the OAE responses enable measurement of cochlear delays and detection of possible multiple internal reflections. Results will be described in terms of the reflection emission theory of OAEs [Zweig and Shera, J. Acoust. Soc. Am. 98, 2018–2047 (1995)] extrapolated to moderate stimulus levels, in which SFOAE nonlinearities are directly related to basilar‐membrane nonlinearities. [Work supported by NIH (R01 DC003784, T32 DC00013).]
The Journal of the Acoustical Society of America 05/2001; 109(5):2373-2374. DOI:10.1121/1.4744355 · 1.50 Impact Factor