Effect of peripheral hearing loss on the masking level difference

Area of Science:

• Audiology
• Auditory Neuroscience
• Speech and Hearing Sciences

Background:

• The masking level difference (MLD) is a psychoacoustic measure sensitive to binaural hearing abilities.
• Peripheral hearing loss, both conductive and sensorineural, can affect binaural processing and MLD.
• Understanding these effects is crucial for accurate audiological assessment and hearing aid fitting.

Purpose of the Study:

• To investigate the impact of symmetric and asymmetric peripheral hearing loss on the MLD at 500 Hz.
• To determine if hearing loss modifies MLD due to threshold deterioration in specific listening conditions.
• To establish correction factors for normal MLD ranges based on hearing loss parameters.

Main Methods:

• Studied 651 subjects with conductive or sensorineural hearing loss and 270 normal-hearing controls.
• Measured MLD at 500 Hz under various conditions.
• Analyzed MLD changes in relation to the degree and type (symmetric/asymmetric) of hearing loss.

Main Results:

• Peripheral hearing loss significantly affects MLD at 500 Hz.
• Deterioration in auditory threshold in the antiphasic condition was identified as the primary cause for MLD modification.
• Established functional relationships between MLD, hearing loss characteristics, and boundary frequency.

Conclusions:

• The study confirms that peripheral hearing loss alters MLD, primarily through impaired antiphasic detection.
• Provides valuable correction factors for interpreting MLD in individuals with hearing loss.
• Enhances the understanding of binaural processing deficits in audiological conditions.