Changes in auditory brainstem responses of normal neonates immediately after birth.
To clarify the functional changes in the acoustic conduction pathway in the human immediately after birth, auditory brainstem responses (ABR) in 58 normal neonates were examined. In longitudinal and cross-sectional analysis, the peak latency of wave 1 showed significant shortening (p less than 0.05) from 1.82 +/- 0.23 ms (mean +/- SD) at 30 min after birth to 1.69 +/- 0.26 ms at 2 h after birth. It continued to decrease gradually therafter. The interpeak latency of waves 1-3 decreased gradually (not significant) from 2.82 +/- 0.19 ms (30 min after birth) to 2.74 +/- 0.15 ms (1 month after birth), while the interpeak latency of waves 3-5 decreased significantly from 2.63 +/- 0.27 ms (30 min after birth) to 2.47 +/- 0.23 ms (24 h after birth; p less than 0.01). These results indicate that functional changes in the acoustic system immediately after birth represent rapid adaptation of the peripheral region to extrauterine environment and development of the more central region.
Yamasaki
M
M
Department of Obstetrics and Gynecology, Saga Medical School, Japan.
Shono
H
H
Oga
M
M
Ito
Y
Y
Shimomura
K
K
Sugimori
H
H
D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn / Q000502:physiology*; D007700:Kinetics