Behavioral Observation Audiometry (BOA) Flashcards
What is the goal of pediatric audiologic evaluations?
To determine whether the child has sufficient hearing (auditory brain access) to develop speech and language
The presence or absence of hearing loss
The degree and configuration of hearing loss
The integrity of the auditory system
What is the normal hearing threshold for peds?
15 dB HL
What is slight hearing loss in peds?
16-25 dB HL
What is mild hearing loss for peds?
26-40 dB HL
What are the most common test protocols for evaluating infants and young children?
Acoustic immittance testing
ABR
Auditory steady-state evoked potential
OAE
Behavioral testing
What indicates a comprehensive audiological evaluation?
Referral from newborn hearing screen
Presence of risk factors
Not startling to loud sounds
Parental concern about hearing or speech delays
What is the gold standard for hearing evaluation for infants and children?
Behavioral evaluation
Why do we need to do behavioral testing?
Enables parents to participate in the testing by allowing them to observe when the infant responds to sounds and when they do not
Allows for cross-check physiologic results with behavioral data by using a battery of tests to determine hearing sensitivity
Can be used to monitor performance with technology
What is procedure selection?
Choosing the right method based on the child’s cognitive and physical development is crucial for accurate test results
What are some things to keep in mind for testing peds?
Procedure selection
Influencing factors (response can be affected by development stage, condition during the test (hungry or tired), and the experience of the audiologist)
Soundfield testing (won’t provide ear specific information, but will provide information regarding whether or not hearing is sufficient to develop speech and language)
Response fatigue (tire quickly)
Importance of setup (vital to ensure assessments are reliable and precise)
What do we have to determine before we can perform behavioral testing?
The child’s cognitive age
Regardless of the child’s chronologic age
How is cognitive information regarding the child (to determine cognitive age) obtained?
Case history
Speech-language or psychoeducational evaluations
If a child has other developmental disabilities, cognitive levels will be harder to ascertain; results of specific developmental tests may be required
How can you estimate developmental age?
From development in other areas of life
Motor and cognitive milestones can provide information, which can help the audiologist plan testing
What are some important developmental milestones (movement) for children?
4 months: Holds head without support
6 months: Rolls front to back; reaches for objects
9 months: Sits up independently; responds to name
12 months: Waves, pulls to stand; walks with support
15 months: Takes independent steps; uses objects correctly
18 months: Walks independently; climbs, points to objects
2 years: Runs, kicks ball; identifies body parts
What audiometric procedure is based on unconditioned responses?
Behavioral observation audiometry (BOA)
What audiometric procedures are based on conditioned responses?
Visual reinforcement audiometry (VRA)
Conditioned play audiometry (CPA)
What is the age range for BOA tesitng?
Birth to 6 months of age
Can also be used for older children with developmental delays or other disorders such as cerebral palsy
How does BOA work?
Involves presenting sounds to a baby who is not actively involved in the task and observing the response (eye widening, change sucking rate, etc.)
What are the things that are being observed in BOA?
Eye widening, quieting, eye shifting, head orienting, arousal, limb movement, respiration changes
What was done for behavioral testing in infants in the 1940s?
Used percussion sounds and pitch pipes to elicit aural reflex responses (eye blinks)
What was done for behavioral testing in infants in 1956?
Infant screening began using pure tones to elicit a reflex (moro) response
What was done for behavioral testing in infants in 1963?
Some clinicians used the infant’s ability to turn toward the sound to assess hearing (between 2 to 4 months)
What is the main problem with the moro reflex response or changes in limb movement or respiration?
Behaviors are not elicited to threshold stimuli, but rather responses to suprathreshold stimuli
What are some advantages of using noisemakers for hearing tests?
Readily available
Simple and inexpensive,
Could be used in any setting (a sound room was not required)
It was believed that infants would respond more reliably to noisemakers than to pure tone stimuli
What are some limitations of using noisemakers for hearing tests?
Very broad frequency responses
Intensity is not easy to control
Can noisemakers fully assess infant hearing?
No, but it can provide some gross information about an infant’s ability to alert to sound and localize to the source
What are some limitations of early testing methods?
Have not proven to be sufficiently repeatable
Are not good indicators of threshold; typically reveal suprathreshold level
What are limitations of ABR, ASSP, and DPOAEs?
They are not direct tests of hearing
They may not always be able to provide a complete and accurate assessment of hearing in early infancy
What is the only way to collect information about an infants ability to hear and attend to auditory stimuli?
Behavioral testing
What does BOA measure?
An infant’s awareness of sound
Doesn’t provide threshold information
Do children typically respond to sounds at threshold? (BOA)
No, they only respond to sounds that are more clearly audible (minimum response levels)
Does BOA have high inter- and intra-subject variability?
Yes
Unable to differentiate between mild and moderate HL
Dependent on state, alertness, attention, etc.
Infant habituation after only a few responses
Should BOA results be used to determine thresholds for purposes of hearing aid fitting?
No, but they may be useful for corroboration of parent/caregiver report
Do infants respond at a lower threshold to speech rather than warble tones and noisemakers?
Yes
They pay attention to what they want to and ignore other things
Is BOA known to have limited reliability?
Yes
Some babies will appear to respond even though they may not have heard it
Others will have heard it but do not demonstrate any observable response
Is cessation or initiation of sucking rate a reliable response for observing auditory behavior in infants younger than 6 months?
Yes
What is being observed during a sucking response?
Changes in the sucking in response to sounds
Observed with bottle, nursing, pacifier (nonnutritive sucking)
Should the baby be hungry during the sucking response?
Yes, but not extremely
Want to avoid them being mad
Do you need to observe the mouth of the baby up close during the sucking response?
Yes
What is an option for sucking response?
Camera with zoom in the testing room that can be controlled from the observation room
Is a sucking response typically present at suprathreshold?
Yes, but are frequently observed at, or close to, threshold
Closer to threshold than the tests in the past
How fast should responses be seen?
Within 2 seconds of the sound presentation (some respond to the sound turning on and some respond to it turning off)
Are infants usually consistent when it comes to their pattern of response?
Yes
Is response time typically slightly shorter for louder stimuli?
Yes
How should the infant be positioned during sucking rate testing?
Infant needs to be resting in a comfortable position with full support of the head and torso and be visible to the tester
Bottle or pacifier: let mother hold in arm
Nursing child: let mother hold in arm
What is the advantage of using a car seat for sucking rate testing?
Infant will not be receiving any “signals” from the mother when he/she hears the sound
How many testers should there be for a sucking test?
A minimum of 2, must reach a consensus
Audiologist (control room)
Audiologist/audiology assistant (next to the infant) - constantly monitor the child making sure his head and torso are comfortably balanced
Both need to have good visualization
Is consistency required for a response?
Yes, if the infant changes something else (eyes widening, moving, etc) it is not considered a response
What is the role of the parent during the sucking test?
Need to remain silent and not react bodily to any sound (even stiffening of the muscles especially for parents who are breastfeeding could be transmitted to the infant)– you can have the mother wear earphones
Making the baby comfortable
Sharing previous baby experience to sound stimulation
At least one parent should be in the room: assist and understand test procedure
Other parent (if present) is invited to stay in the observation room
Do infants only provide a limited number of responses during a session?
Yes
Is ear specific information always necessary for infants?
No, it may not be required for the initial visit unless a medical condition warrants ear specific info
If there is any evidence of hearing loss without ear specific information, what is needed?
Ear specific information
Need to test under earphones
When should ear specific information be collected?
Same day or different day
What is stimuli used for frequency specific information?
Warble tones
Narrow band noise
Can speech sounds be used to confirm warble tones/noise band threshold levels?
Yes
Threshold for “ba” should be close to threshold obtained at 500 Hz
Threshold for “sh” should be close to threshold obtained at 2000 Hz.
Threshold for “s” should be close to threshold obtained at 3000 to 4000 Hz
What frequency should you begin testing at for infants?
Many normal hearing infants respond better to high-frequency stimuli, so it is reasonable to begin at a high frequency, usually 2000 Hz
If SNHL is suspected, start at 500 Hz
If there is a concern about ME pathology, start at 2000 Hz
What should you do after obtaining thresholds at 500 and 2000 Hz?
Determine the next most important piece of information
For example, if thresholds at both 500 and 2000 Hz are normal, it’s more useful to test 4000 Hz than 1000 Hz. However, if hearing at 500 Hz is 30 dB HL and at 2000 Hz is 70 dB HL, testing 1000 Hz becomes crucial
Do you need to present the stimuli at an appropriate pace?
Yes, if it is presented too fast, the infant will ignore them
Should you start presenting the stimuli from silence?
Yes, sounds emerging from silence are more likely to get a response
Should you watch the infant closely for a response?
Yes
Are response patterns more apparent for loud sounds?
Yes
Loud sounds help identify response types and latencies, aiding interpretation of softer sounds
What are other factors that influence BOA?
Spending a little time with the infant before beginning testing to ensure that they can perform the required task will increase the likelihood of obtaining reliable test results
Gastrointestinal feeding tube (cannot do feeding response)
Infant’s neurologic status
Visually alert
How do you have good response reliability during BOA testing?
Predetermine what constitutes a response
Stick to the chosen response (e.g., sucking) and avoid accepting other behaviors like eye widening or head turns
Avoid changing response criteria during testing
Ensure the response is time-locked to the stimulus presentation
Responses must be repeatable
Use multiple observers to increase reliability
What is the BOA test protocol?
Reduce thresholds in 10 dB steps and increase in 5 to 10 dB steps
Take breaks as needed to calm the infant and increase usable test time
If SF testing indicates hearing loss, test bone
If infant is still responding, or at the next test session, test with insert earphones
What are some benefits of BOA?
Enables the audiologist to obtain valuable behavioral responses in infants; part of the cross-check principle
Can be conducted in sound fields, with earphones or with bone oscillator, hearing aids, or cochlear implants
Enables accurate fitting of technology because minimal response levels (MRLs) can be obtained
What are some limitations of BOA?
Requires careful observation of infant sucking by the audiologist
Cannot be used with infants who do not suck (e.g., infants who use feeding tubes)
Can be performed only when the infant is in a calm awake or light sleep state
BOA not generally accepted in the audiology community because audiologists typically have not been trained to use a sucking response paradigm
