Behavioral audiometry: protocols for measuring hearing thresholds in babies aged 4-18 months

Area of Science:

• Pediatric Audiology
• Developmental Pediatrics
• Hearing Science

Background:

• Accurate hearing assessment in infants, especially those with developmental challenges, is crucial for early intervention.
• Existing audiometry protocols may be difficult to implement in very young children and those with multiple handicaps.

Purpose of the Study:

• To present original behavioral audiometry protocols for measuring hearing thresholds in very young children (4-18 months).
• To include protocols specifically adapted for multiply handicapped infants.
• To enable early and comprehensive hearing assessment across the full frequency range.

Main Methods:

• Utilized bone conduction vibrator testing, unaffected by middle ear infections, as a key diagnostic step.
• Employed air conduction testing with headphones, using a unique setup to elicit reliable 'surprise reactions'.
• Replaced classical visual reinforcement with interactive, dynamic play-based exchanges between examiner and child.

Main Results:

• Tested 105 infants (4-18 months) with bilateral sensorineural hearing loss.
• Achieved full bilateral air conduction results in 82.4% of non-handicapped infants before 12 months.
• Obtained results in multiply handicapped infants, with 37.5% achieving full bilateral air conduction before 12 months.

Conclusions:

• The developed protocols facilitate early measurement of hearing thresholds across all frequencies.
• These methods are effective even in multiply handicapped infants and those with developmental delays.
• The protocols enable timely diagnosis and intervention, minimizing sessions required.