Use of performance-intensity functions for diagnosis

Area of Science:

• Audiology
• Neuroscience
• Speech-Language Pathology

Background:

• Understanding speech perception in noise is crucial for individuals with hearing loss.
• Performance-intensity (PI) functions assess speech discrimination across varying sound levels.
• Distinguishing between cochlear and retrocochlear hearing loss is vital for effective management.

Purpose of the Study:

• To analyze performance-intensity functions for phonetically balanced word lists in normal hearing, cochlear, and retrocochlear hearing loss groups.
• To identify characteristic patterns in speech discrimination related to the type of auditory disorder.
• To investigate the presence and severity of the rollover phenomenon in different patient groups.

Main Methods:

• Obtained performance-intensity functions using phonetically balanced word lists.
• Recruited participants with normal hearing (27 ears), cochlear disorders (89 ears), and retrocochlear disorders (8 ears).
• Analyzed speech discrimination scores at different speech presentation levels.

Main Results:

• Normal hearing and cochlear disorder groups showed mild to moderate reductions in discrimination scores above the phonetically balanced word maximum.
• Retrocochlear disorder group demonstrated a pronounced rollover phenomenon.
• A rapid decline in performance was observed in retrocochlear patients as speech level increased past the maximum discrimination score.

Conclusions:

• The rollover phenomenon is a significant indicator differentiating retrocochlear hearing loss from cochlear impairments and normal hearing.
• Performance-intensity functions provide valuable insights into the neural processing of speech.
• Further research can refine diagnostic criteria based on these auditory function patterns.