Pediatric behavioral audiometry refers to a subjective hearing assessment method. The examiner determines a child's auditory sensitivity (hearing threshold) by observing the child’s behavioral responses (e.g., turning their head toward the sound source or performing specific actions) upon perceiving a sound. The test results provide information about the degree and nature of hearing loss (conductive, sensorineural, or mixed) and offer an estimation of the potential communication disorders caused by hearing impairment in children.
The reliability and accuracy of the test results largely depend on the child’s age and developmental maturity, as active cooperation is required. Factors such as the child's chronological age, intellectual level, social interaction skills, and speech development make subjective hearing assessments in children more challenging compared to adults. The experience and technical proficiency of the clinical tester often play a crucial role in the success of the test. Based on the age of the test subject, commonly used and well-established clinical methods of pediatric behavioral audiometry include Behavioral Observation Audiometry (BOA), Visual Reinforcement Audiometry (VRA), and Play Audiometry (PA). Additionally, speech tests (including infant speech audiometry) may also be conducted for children with some level of verbal ability.
Behavioral Observation Audiometry (BOA)
Behavioral observation audiometry is a method used to preliminarily evaluate the hearing status of infants aged six months or younger. When an infant is in a light sleep or quiet state, a high-intensity sound stimulus is presented. Observations are made within a time-locked window to determine whether the infant exhibits noticeable auditory behavioral responses (e.g., eyelid reflexes) upon hearing the sound. This method is also commonly used as a supplementary tool alongside VRA and play audiometry or for basic hearing evaluations in infants who cannot use conditioned response techniques due to special cases.
The most commonly used stimuli in BOA are those produced by “noisemakers” (e.g., sound toys), but recorded or electronically generated stimuli, as well as broadband noise or speech sounds, can also be used as sound stimuli.
Visual Reinforcement Audiometry (VRA)
Visual reinforcement audiometry is the most widely utilized method of conditioned orientation response testing, which uses visual stimuli to reinforce a child’s responses to sound stimuli in order to obtain information about their auditory reactions. The method is based on Conditioning Orientation Reflex (COR), a behavioral testing technique that pairs auditory stimuli with a reinforcing condition to maintain the child’s interest in sound stimuli and ensure response consistency over time.
This technique is grounded in the physiological phenomenon that typically developing infants, aged 4 to 6 months, begin to exhibit the ability to localize sound sources. Visual reinforcement audiometry combines auditory stimulation with visual rewards to engage the child and encourage them to orient toward the sound source. Over time, the child establishes a conditioned orientation reflex of “hearing the sound → seeking the reward.” This approach motivates the child to continue responding even when they may lose interest in the auditory stimuli.
The method assumes that the child’s behavioral responses are highly specific, characterized by an immediate head-turn toward the sound source paired with a visual reward upon hearing the sound stimulus.
Visual reinforcement audiometry is highly effective as a behavioral assessment tool. By optimizing test conditions, it can be used for hearing screening, identifying the degree of hearing loss, evaluating the effect of hearing aids or cochlear implants, and assessing speech development and communication abilities. This method is commonly used for children aged 7 months to 2.5 years.
Play Audiometry
Play audiometry involves engaging a child in a simple, enjoyable game and teaching them to produce clear and reliable responses to auditory stimuli. The child being tested needs to understand and perform the required task and wait for the sound stimulus to appear before responding. During testing, the child performs a specific task upon hearing a sound stimulus, such as placing rings on a peg or dropping blocks into a basket.
This method establishes a conditioned response by associating hearing a sound with performing an action. By observing the child’s completion of a specific action after hearing a sound, the air conduction and bone conduction hearing thresholds at various frequencies can be determined. The results indicate the degree and type of hearing loss (conductive, sensorineural, or mixed) and assess the impact of hearing loss on the child’s communication abilities.
Play audiometry is typically used for children aged 2.5 to 6 years. For children with severe hearing loss or multiple disabilities who are unable to engage in clear and reliable communication, this method may also be suitable for older children, even up to 10 years of age.
Infant Speech Audiometry
Infant speech audiometry assesses a child’s ability to detect and recognize speech stimuli by using verbal signals as auditory stimuli. This method analyzes the relationship between the linguistic perception results of hearing-impaired children and the type, degree, and nature of their hearing loss. It provides valuable reference information for clinical diagnosis, treatment, and rehabilitation, facilitating early identification, diagnosis, and intervention.
Speech tests, used in both clinical settings and research, allow for the classification of hearing loss types and degrees, as well as localization of the damaged site. They also assess the auditory function of the individual in daily life by evaluating their ability to understand simple, everyday spoken language. The effects of medications, surgeries, hearing aids, or cochlear implants can also be evaluated with this method.