Hearing in Hearing in ChildhoodChildhood

TLA SIN Due todayTLA SIN Due today

Paperette due FRIDAY Paperette due FRIDAY 9:15 AM in class (hard copy)9:15 AM in class (hard copy)

Electronic copy must be emailed to Electronic copy must be emailed to Mike Mike

by 5 pm Fridayby 5 pm Friday

Fetal AuditionFetal Audition Deafness screeningDeafness screening

Ultrasound probingUltrasound probing Test at-risk vs. healthyTest at-risk vs. healthy Light/sound Light/sound

responsivenessresponsiveness Early warning (33 weeks Early warning (33 weeks

of gestation)of gestation) Early recognitionEarly recognition

Story reading in wombStory reading in womb Infant prefers exposed Infant prefers exposed

story to novelstory to novel Infant prefers mother’s Infant prefers mother’s

voicevoice

Baby HearingBaby Hearing Auditory system Auditory system

Outer/middle/inner ear, brain Outer/middle/inner ear, brain stem, midbrainstem, midbrain

Small, but fully developed at birth Small, but fully developed at birth Cortical development continues Cortical development continues

through first yearthrough first year Low frequency hearing (< 10 Low frequency hearing (< 10

kHz)kHz) Poor at birthPoor at birth

Thresholds 2x adultsThresholds 2x adults Slow development (2-10 years)Slow development (2-10 years)

High frequency hearing (> 10 High frequency hearing (> 10 kHz)kHz) Near adult levels at birthNear adult levels at birth Improves to peak performance at Improves to peak performance at

6 mos6 mos

Testing BabiesTesting Babies Challenge of Baby researchChallenge of Baby research

What is a response?What is a response? Sucking rateSucking rate

Habituation paradigmHabituation paradigm Ad naseumAd naseum exposure to a stimulus exposure to a stimulus

Change stimulusChange stimulus Dishabituation vs. habituationDishabituation vs. habituation

Bored baby wakes up?Bored baby wakes up?

Sample challengesSample challenges Loss of subjectsLoss of subjects

Localization in infantsLocalization in infants Can infants detect interaural Can infants detect interaural

differences?differences? (loudness differences between the (loudness differences between the

ears); (time difference between the ears); (time difference between the ears)ears)

Recently born 10 minutesRecently born 10 minutes (Green, (Green, 1976)1976)

Orienting response to rattleOrienting response to rattle Loudness, timing or both?Loudness, timing or both?

Exp. 9 week old infants Exp. 9 week old infants (Clifton et al., (Clifton et al., 1984)1984)

Loudness, timing combo of cuesLoudness, timing combo of cues Predict: which is better for infants?Predict: which is better for infants?

Both cues effective at 5 mosBoth cues effective at 5 mos

Baby Cries Baby Cries (Dondi et al., 1999; Martin (Dondi et al., 1999; Martin & Clark, 1982)& Clark, 1982)

Newborn:Newborn: Exp: presentation of Exp: presentation of

own crying vs. other own crying vs. other infant vs. similar noise infant vs. similar noise eventevent

Predictions? Which Predictions? Which causes the baby to cry causes the baby to cry the most?the most? Noise event not as strong Noise event not as strong

a reaction as baby cryinga reaction as baby crying Self-cry discriminationSelf-cry discrimination

Sucking response Sucking response greater to novel crygreater to novel cry

The Mozart Effect The Mozart Effect (Rauscher et al., 1993; Thompson et al., (Rauscher et al., 1993; Thompson et al.,

2001)2001) Short-term improvement of Short-term improvement of

spatial abilityspatial ability Children perform task Children perform task

with/without Mozartwith/without Mozart 10 – 15 minute improvement in 10 – 15 minute improvement in

performanceperformance EXP. Albinoni music vs. EXP. Albinoni music vs.

Silence vs. MozartSilence vs. Mozart Predictions?Predictions? Performance correlates with Performance correlates with

arousalarousal Debunking Mozart’s effect?Debunking Mozart’s effect?

Music training correlates with Music training correlates with improved IQimproved IQ Small, consistent effectSmall, consistent effect Attendance and Small classesAttendance and Small classes