The results suggest that different aspects of auditory processing mature at different age periods and these maturational effects need to be considered while assessing auditory processing in children.

Background: Present study investigated the relationship between speech identification scores in quiet and parameters of cortical potentials (latency of P1, N1, and P2; and amplitude of N1/P2) in individuals with auditory neuropathy.

Objective: The study aimed at exploring the audiological characteristics and the relationship between speech identification scores with cortical evoked potential measures and hearing aid benefit in individuals with auditory neuropathy spectrum disorder (ANSD). Study design: We initiated a retrospective study of patients who were diagnosed as having ANSD. In 198 patients with ANSD, patient history, risk factors, degree and configuration of hearing loss, speech identification scores in quiet and noise, otoacoustic emissions (OAE), immittance evaluation, auditory brainstem responses (ABR), long latency responses (LLR) and hearing aid benefit were assessed. Results: The results showed that the majority of the patients had bilateral ANSD with a female to male ratio of 1.25:1 with the majority having a rising configuration of hearing loss. OAEs were present in most with absent stapedial reflexes and ABR. The study also showed that individuals with ANSD do obtain benefit from hearing aids and it is related to the presence of LLR. Conclusions: The present study emphasizes the audiological characteristics of a large group with ANSD. Among the management options, hearing aids were found to be useful in only a few of the patients and other rehabilitation options, such as cochlear implants, need to be explored in future studies. Currently, the determining factors for benefit with hearing aid are speech identification scores and cortical auditory evoked potentials.

AimThe present study evaluated the relation between speech perception in the presence of background noise and temporal processing ability in listeners with Auditory Neuropathy (AN).MethodThe study included two experiments. In the first experiment, temporal resolution of listeners with normal hearing and those with AN was evaluated using measures of temporal modulation transfer function and frequency modulation detection at modulation rates of 2 and 10 Hz. In the second experiment, speech perception in quiet and noise was evaluated at three signal to noise ratios (SNR) (0, 5, and 10 dB).ResultsResults demonstrated that listeners with AN performed significantly poorer than normal hearing listeners in both amplitude modulation and frequency modulation detection, indicating significant impairment in extracting envelope as well as fine structure cues from the signal. Furthermore, there was significant correlation seen between measures of temporal resolution and speech perception in noise.ConclusionResults suggested that an impaired ability to efficiently process envelope and fine structure cues of the speech signal may be the cause of the extreme difficulties faced during speech perception in noise by listeners with AN.

The main aim of this study was to use spectral smearing to evaluate the efficacy of a spectral ripple test (SRt) using stationary sounds and a recent variant with gliding ripples called the spectro-temporal ripple test (STRt) in measuring reduced spectral resolution. In experiment 1 the highest detectable ripple density was measured using four amounts of spectral smearing (unsmeared, mild, moderate, and severe). The thresholds worsened with increasing smearing and were similar for the SRt and the STRt across the three conditions with smearing. For unsmeared stimuli, thresholds were significantly higher (better) for the STRt than for the SRt. An amplitude fluctuation at the outputs of simulated (gammatone) auditory filters centered above 6400 Hz was identified as providing a potential detection cue for the STRt stimuli. Experiment 2 used notched noise with energy below and above the passband of the SRt and STRt stimuli to reduce confounding cues in the STRt. Thresholds were almost identical for the STRt and SRt for both unsmeared and smeared stimuli, indicating that the confounding cue for the STRt was eliminated by the notched noise. Thresholds obtained with notched noise present could be predicted reasonably accurately using an excitation-pattern model.