Conditioned Play Audiometry (CPA) Notes
What is Conditioned Play Audiometry (CPA)?
A method of testing hearing in toddlers/preschoolers via conditioned motor responses to sound using game activities.
Described by Hoversten and coworkers in the ; protocol adapted with minor modifications over time.
Target population
Appropriate for testing children from 30 months of age through 5 years of age
Play audiometry is effective for children cognitively older than 3 years but challenging for children younger than 2.5 years
Audiologist's responsibility
Success depends on preparation, technique, and behavior management.
Be creative to keep children engaged and cooperative.
If testing is unsuccessful, the audiologist should state, “I was not able to test this child today,” not label the child as untestable.
Performing CPA
No standardized guidelines exist; based on clinical experience and best practices from VRA.
CPA has two phases: (1) Teaching/conditioning/instruction phase; (2) Testing phase.
Readiness and setup (Ready, Set, Play!)
Determine developmental readiness (cognitive age is key).
Readiness indicators: normal motor and speech/language development; no significant developmental disorders; prior testing history can aid readiness.
Test environment setup
Ideal: two-room setup (audiologist in control room, tester in sound room).
Tester manages child and reinforces behavior; effective for soundfield testing.
In single-tester setups, first train child to respond to stimuli without earphones.
Some clinics use one-room setups with loudspeakers; requires a second tester for efficiency.
Select age-appropriate play task
Keep child entertained for long enough to complete testing.
Motor response should be simple for operant conditioning but not so easy it becomes boring.
Balance task difficulty to avoid fatigue or loss of motivation.
Choosing the right type of game
Games with a definitive end point motivate some children but may require reconditioning when switching games.
Games with an ongoing feel keep attention longer; reduce the need to change toys.
Be cautious with tasks requiring fine dexterity.
Activities used in play audiometry (examples)
Toss a ball into a basket when sound is heard
Place a puzzle piece when sound is heard
Put the ring on a cone when sound is heard
Place a peg in a pegboard when sound is heard
Give mom/dad a high-five when sound is heard (no toys available)
Place a block on a castle when sound is heard
Increase interest and infection control
Have a variety of engaging toys to maintain attention.
Remember infection control practices.
Be creative when needed
Flexibility to modify tasks to maintain engagement.
Conditioning and conditioning process
Condition the response: pair auditory stimulus with a motor task and reinforcement.
Core elements: Auditory stimulus, Behavioral reinforcement, and the motor response.
Teaching, conditioning, and instruction phase
Get the child into a ready state; teach the response before formal testing.
Model and practice the response task.
Condition the response to the onset of the auditory stimulus.
Instruction matters
Older children: simple direct instructions (e.g., “When you hear the sound, place the man in the boat and keep doing this for every sound.”
Younger children: playful, engaging instructions with practice.
Conditioning steps
Step 1: Assistant demonstrates task with direct eye contact, holds toy near ear, says “I hear that” when sound is present, drops toy into bucket.
Step 2: Assistant with child performs task; helps child drop the toy when sound is heard.
After a few trials, the tester should feel the child’s hand move in the proper order.
Conditioning to vibrotactile stimulus
If uncertain whether the child heard the sound, condition with a bone vibrator (250 Hz) from the audiometer.
Bone vibrator can be placed on the mastoid, in the child’s hand, or on the knee.
Once conditioned to the vibrator, return to air-conducted stimulus and retry.
Targeted response and timing
The child holds a toy up to the ear and drops it in the bucket when a sound is heard.
If hesitant, involve parents in the game; increase intensity and repeat conditioning trials.
If successful, move to phase 2.
Positive reinforcement
Common forms: verbal praise (e.g., “that’s good”), social reinforcement (pat on the back, smile), tokens for toys/stickers, or cereal.
Start with a 100% reinforcement schedule (reward every correct response) and gradually shift to intermittent reinforcement.
If unsure, better to withhold reinforcement to avoid reinforcing a false response.
Acceptable behavioral responses
A response must be deliberate, consistent with motor skills, and time-efficient.
Acceptable window: a response within 2-3 seconds after stimulus onset and no later than 4 seconds
Managing response behaviors
False responders: respond without a stimulus; use a subtle reminder near the response hand to reduce false positives.
Reluctant responders: delay responses; look for subtle facial reactions; assist and monitor next stimulus.
Off responders: wait for the sound to stop before responding; continuous tones may help.
Acceptable behavioral responses (cont.)
Spend sufficient time in the teaching phase to elicit robust responses.
Return to teaching if hesitant responses occur (e.g., hovering the toy, looking for reassurance, incomplete actions).
Transducers and test parameters
Testing modalities: Earphones, Bone conduction, Hearing aids, Cochlear implants, FM systems.
Ear-specific information
Ear-specific results require earphones; otherwise results are reported for the better ear.
Supra-aural vs insert earphones
Supra-aural: easier to put on and remove; heavier on small heads; needs correct placement.
Insert earphones: easier to insert; less monitoring required; may provide better test results but require more effort to insert.
Selecting test stimulus
Stimuli options: Warble tones, Narrowband noise (NBN), Speech, BBN, Pedestrian (PED) noise, Music.
Start simple and progress
Begin with tasks requiring the least cooperation; if resistance to earphones, start in soundfield, obtain 2–3 thresholds, then try earphones.
Starting with speech
If child responds to speech, start with a speech stimulus to improve engagement.
After conditioning to listen-and-drop, switch to tones or NBN to obtain an audiogram.
For developmentally delayed children, use tones, NBN, or music.
Threshold estimation and presentation
Step sizes: to maximize attention; smaller steps near threshold.
Threshold criterion: two out of three ascending responses.
Start at or ; then obtain thresholds at or as appropriate.
If using headphones, alternate between ears; if four frequencies per ear are obtained, obtain bone conduction thresholds as well.
Assessing response reliability
Use control trials (no-sound trials) to identify false-positive responses.
If false positives occur, revisit teaching phase or switch games to slow response pace.
No-sound trials reveal the rate of false positives; excessive false positives may require a new approach.
Expected testing outcomes
A complete audiogram includes AC and BC thresholds from to in each ear.
Young children may provide limited responses in a single session.
Goal: obtain reliable thresholds via a play-based task and quantify degree, type, and configuration of hearing loss.
Child should reliably provide two consecutive, unprompted correct responses before threshold testing.
Testing with bone conduction
Use BC when there is concern about a conductive component or when hearing loss is suspected.
Challenge: placing the transducer.
Typically obtain two to three thresholds if attention is an issue.
Conductive HL: critical frequencies ; SNHL: are most important.
Begin testing with bone conduction
Use foam supports and Velcro head band to secure the transducer.
Testing children with hearing loss
Mild/moderate loss or conductive losses: no special adaptation required.
Severe/profound losses (especially if not identified in infancy): may require adaptations (e.g., attach probe from insert earphones to earmolds; tactile stimulation with bone vibrator if no response at limits).
Once consistent responses are obtained, begin testing with earphones at or .
Computer-assisted testing
Child interacts with a computer via a mouse; screen presents features (e.g., hats on a clown).
Audiologist controls the test from the control room.
What to do if the child will not cooperate?
Do not offer non-bona fide choices; avoid switching to different test techniques like VRA.
If cooperation is difficult: take a short break; introduce new toys; try a new assistant; involve the parent as assistant; try a new stimulus; consider a gentle bribe.
Additional strategies for non-cooperation
Allow the child to sit on the parent’s lap.
Use transparent expectations about test duration (e.g., “when we finish this game, we are done”).
CPA: Benefits & challenges
Benefits: accurate responses at threshold; flexible testing in soundfield or with earphones, bone oscillator, hearing aids, cochlear implants.
Challenges: keeping the child engaged long enough to obtain necessary information.
Box 7.3 Test Protocol for Conditioned Play Audiometry (summary)
Seat the child comfortably; select an enjoyable toy.
Begin with a stimulus the child is expected to hear.
Demonstrate the task, then have the child perform with guidance.
Ensure the child drops the toy only when the sound is heard.
Repeat until the child performs reliably without assistance.
If bored, change toys to maintain interest.
Testing can be conducted with air conduction, bone conduction, and with various devices (hearing aids, cochlear implants, FM, etc.).
Conventional audiometry (for older children)
For children older than , conventional audiometry is used: the child raises a hand or presses a button in response to stimuli rather than performing a play task.