I. Decibel Revisited
A. dB SPL-- The unit of sound intensity measured with the ____________.
A dB SPL plot begins with 0 at the _________ of the ordinate. The normal audibility curve shows that our hearing is most sensitive in the _________ frequencies. The reference values used in calibrating the _________ comes from this normal audibility curve.
B. dB HL-- Unit of sound intensity when measuring hearing with an audiometer that normalizes the average threshold values in dB SPL to _________ dB HL.
The normal audibility curve in dB HL is a _________ line. At 1000 Hz, for a TDH 39
earphone, _________ hearing is 7 dB SPL. Therefore, 40 dB HL is equivalent to _________ dB SPL. The value in dB SPL will always be _________ than the equivalent value in dB HL.
C. SPL/HL Conversions--A curve that is flat on a dB SPL plot will be _________ on a dB HL plot with better hearing in the _________ and _________ frequencies.
A curve that is parallel to the normal audibility curve in dB SPL will be _________ on a dB HL plot. A curve that is a reverse-cookie bite on the dB SPL plot will be _________ on a dB HL plot.II. Pediatric Protocol
A. Important Factors in the Sound Field
1. Angle-Azimuth refers to the position of the __________ relative to the speaker delivering the signal. It is determined in degrees. Child sits at __________ or __________ degrees from speakers most often. The sound field is calibrated to a certain degree azimuth (usually 45 deg). The sound arriving at the ear is influenced by __________ and __________ effects. With child at __________ from speaker the ear canal is at a direct channel to the speaker and the ear canal resonance is high.
2. Distance from speaker- Typically the distance between patient and loudspeaker is __________ but may be different for each room.
3. Stimuli- Warble tones better for sound field because of the limited signal variation with head movement, but the tradeoff is reduced _______________. Pure Tones are more frequency-specific but bounce off walls and can vary greatly in level with movement of the client. The __________ the spectrum of the signal, the less the SPL varies with head movement. Narrow-band noise is more stable than warble tones, however, threshold may be __________ if there is a steeply sloping hearing loss.
B. Procedures with Children
1. Threshold Testing Behavioral Observation Audiometry (BOA)- Appropriate for infants birth to __________ months. Observe responses to sound (sucking,startle) and responses during no sound trials or __________trials. There is no reinforcement.
Conditioned Oriented Response (COR)- Appropriate for infants 6 mos to children __________yrs. The examiner pairs sounds with particular responses and gives __________ by visual lights(VRA) or puppet (PIWI).
Tangible Reinforcement Audiometry is for the hard-to-test. Greater motivation is provided with food or other tangible reinforcement.
Computer Play Reinforcement- Button is pressed when sound is heard and computer adds something to the screen.
Play Audiometry- Appropriate for children 2-3 yrs to __________ yrs. Child
responds to sound by manipulation of toys. Preferably there is a __________ goal such as trying to swat a family of mosquitoes. Toys with appropriate parts
include blocks, pegs, puzzles.2. Materials for Speech Recognition 2-4 yrs- familiar words such as body parts, closed set; ideally have __________ choices to keep guessing minimal.
3-5 yrs- NUCHIPS- Northwestern Univ. Children’s Pictures. Child points to one of __________ pics per page.
4-6 yrs- WIPI- Word Intelligibility by Picture Identification. Panel of __________ similar sounding pictures per page.
6-14 yrs- PBK’s Phonetically Balanced word lists. No __________, words are repeated.
__________ Yrs-HINT-Hearing In Noise Test for Children--Test is given in the sound field with __________ noise. Child repeats a whole sentence. A signal-to-noise ratio is determined for __________ correct recognition.
14yrs- Standard adult lists, __________ or NU6, may be used.
III. Audiogram Review
A. Simple Rules
1. Pure Tone Average and Speech Reception Threshold should agree within __________ of each other.
2. Thresholds for tones may be worse than for speech with children because they are __________. If the threshold for speech is worse, it may be suggestive of a central disorder or __________ problems.
3. Speech Awareness Threshold should agree with the 250-500Hz threshold within 10dB. This is where the most __________ is contained in the speech signal.
4. Speech Recognition Testing also know as word __________ is typically given at ______ to ______ dBSL
5. Masking-Masking is necessaryfor air conduction, if the AC 0 in the test ear-40>BC 0 in the ________.
6. Masking-Masking is necessary for --bone cond. if .....the Air bone gap > __________.
7. Masking is needed during speech recognition testing if the __________ minus 40 > best BC 0 in the non-test ear at any frequency.
IV. Pediatric ResponsesB. Interpretation of Speech Recognition Scores
Thornton & Raffin tables show the __________ between 2 scores to be considered a significant difference. Use the first score to find the range in the table. If the second score is __________ this range, it is considered to be significantly different. If it is __________ the range, it is highly likely that score would be achieved on subsequent administrations just due to chance variability. The more words that are presented in a given test, the more __________ the test is, i.e. the critical difference range becomes __________. In order to determine if a significant change in speech recognition has occurred, one must know how many __________ were presented. For example, two scores 65% and 85% would be significantly different if _____ words were presented but would not be significantly different if ____words were presented.
Localization
Newborn: Arousal
_____: Beg. Head Turn
_____: Horizontal only
_____: Horizontal & down
_____: Horiz, down, & up
_____: Localizes directly
Response Levels
Startle-Should occur for speech at ________ regardless of age (Downs, 1974) Minimum Response Levels vary by___ _______ _________ ____
Compare Martin & Clark (1996) Table 6.1 with Gravel (2000) Table 2
Conclude:
Variability is less with____________
Responses are lower with __________
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