# Assessment of Peripheral and Central Auditory Processing after Treatment for Idiopathic Sudden Sensorineural Hearing Loss

## TL;DR

This study found that successful treatment of sudden hearing loss does not fully restore normal auditory processing, suggesting central auditory system involvement.

## Contribution

The study introduces a within-subject design to compare peripheral and central auditory processing in treated sudden hearing loss patients.

## Key findings

- Otoacoustic emissions were poorer in treated ears compared to normal ears.
- Ear- and sex-dependent differences were observed in otoacoustic emissions and pitch discrimination.
- Asymmetrical auditory processing was observed, not aligned with hearing threshold values.

## Abstract

Introduction
 When cases of idiopathic sudden sensorineural hearing loss (SSNHL) are treated successfully, most clinicians assume the normality and symmetry of the auditory processing. This assumption is based on the recovery of the detection ability on the part of the patients, but the auditory processing involves much more than detection alone. Since certain studies have suggested a possible involvement of the central auditory system during the acute phase of sudden hearing loss, the present study hypothesized that auditory processing would be asymmetric in people who have experienced sudden hearing loss.

Objective
 To assess the physiologic and electrophysiological conditions of the cochlea and central auditory system, as well as behavioral discrimination, of three primary aspects of sound (intensity, frequency, and time) in subjects with normal ears and ears treated successfully for SSNHL.

Methods
 The study included 19 SSNHL patients whose normal and treated ears were assessed for otoacoustic emissions, speech auditory brainstem response, intensity and pitch discrimination, and temporal resolution in a within-subject design.

Results
 The otoacoustic emissions were poorer in the treated ears compared to the normal ears. Ear- and sex-dependent differences were observed regarding otoacoustic emissions and pitch discrimination.

Conclusion
 The asymmetrical processing observed in the present study was not consistent with the hearing threshold values, which might suggest that the central auditory system would be affected regardless of the status of the peripheral hearing. Further experiments with larger samples, different recovery scenarios after treatment, and other assessments are required.