Auditory Development

Question 1

Why do children detect high frequencies better? About what what age is detection level about the same?

Answer 1

Smaller ear canals, and because the tympanic membrane is mass dominated at this stage; 6-12 months

Question 2

Small ear canals contribute to high F how?

Answer 2

The smaller tube creates smaller wavelengths thus intensifying high frequencies

Question 3

Mass dominated TM contribute to high F how?

Answer 3

the mass dominated impedance prefers high F, although low F vibrate the TM more.

Question 4

Auditory response birth - 4months

Answer 4

The startle response is normal at this age to intensities of 65 dB. Moro reflex.

Question 5

Auditory response 3-4 months

Answer 5

slow head turn to one side ; can parse out suprasegmental aspects of sound

Question 6

Auditory response 4-7 months

Answer 6

can do a head turn to one side, should be able to lift the head and shoulders, by 7 mo. should start turning head in both directions (lateral plane only) should sit without support at 7 mo.

Question 7

Auditory response 7-9 months

Answer 7

Can start doing VRA. The infant should be consistent with head turns to either side. may start babbling (6 months). Can sit up without assistance

Question 8

Auditory response 9-13 months

Answer 8

At the end of the 13 mo. the child should be able to localize in all directions (lateral and elevation). At 12 mo. full maturation of auditory system.

Question 9

CNS dysfunction

Answer 9

Infants with CNS dysfunction are not able to habituate to sounds in their environment, get startled every time.

Question 10

Canonical babbling

Answer 10

Appears at 5-6 months; well defined mature syllables, clear vocal sound w/consonant margins, not associated with meaning yet

I.e. marginal babbling