The Journal of the Arkansas Medical Society Issue 2 Vol 115 | Page 12

A
C L O S E R
L O O K
AT
Q U A L I T Y
EDITORIAL PANEL
Chad T. Rodgers, MD, FAAP; Elena M. Davis, MD, MPH;
Michael Moody, MD; J. Gary Wheeler, MD, MPS
Infant Hearing Loss:
A Neurodevelopmental Emergency
BY ALAN MEASE, MD, FAAP
T
wo or three of every 1,000
children in the United States
are born with some degree of
hearing loss. Even more will lose their
hearing during infancy or childhood.
The most important period of speech
and language development occurs
during the first three years of life,
when the brain is constructing nerve
pathways necessary for understand-
ing speech.
Hearing is a brain function and a
baby’s brain is “pre-wired” to ac-
cept and process sound. Babies with
typical hearing begin hearing be-
fore birth, at 20 weeks’ gestation. At
birth, babies prefer listening to their
mother’s voice, their native language,
human speech rather than noise, and
songs or stories heard before birth.
Hearing loss in babies is a “neuro-
developmental emergency.” The brain
is the true organ of hearing; the ears
only transmit sounds to the brain.
Babies born with hearing loss are
not starting from the same point as a
baby with normal hearing. They have
missed 20 weeks of typical develop-
ment of their auditory pathways be-
fore birth. They will miss the auditory
neural development that occurs after
birth, before hearing loss is diag-
nosed. They will miss the typical de-
velopment of auditory brain pathways
that could have occurred after birth,
until the child begins hearing sounds
consistently by wearing hearing aids
during all waking hours.
A baby’s brain must be exposed to
meaningful sounds consistently for
auditory neural pathways of multiple,
spiral, ganglion neurons in the brain
to develop. 1 If a baby does not hear
sounds well or is exposed to only a little
sound or speech during his or her early
years, then a permanent re-assignment
of the child’s auditory brain cells occurs.
If the brain is not stimulated by sound,
it will reorganize itself through synap-
tic pruning to maximize processing
through other senses, primarily vision.
After about three-and-a-half years of
age, the brain has considerably less
flexibility to develop effective skills
to process auditory information. This
is why children with hearing loss will
experience difficulty learning to listen
and speak proficiently. 2
In 1999, the Arkansas General As-
sembly passed Act 1559, implement-
ing early detection of hearing loss at
all birthing facilities. This law resulted
in Arkansas’ Early Hearing Detection
and Intervention (EHDI) program.
EHDI is responsible for successfully
screening 98.4 percent of all babies
born in Arkansas. Screening identi-
fies about 50 babies per year with
hearing loss. Unfortunately, only 15
percent of them receive early inter-
vention services by six months of age.
The Centers for Disease Control and
Prevention (CDC), American Acad-
emy of Pediatrics, EHDI and the Joint
Commission on Infant Hearing (JCIH)
created consensus guidelines to have
all babies receive early intervention
by six months of age. 3
Timing is critical to optimize
outcomes. Babies with hearing loss
identified in the first weeks of life, and
who begin hearing optimally no later
than six months, have a good chance
of developing neural connections in
their auditory brain pathways neces-
sary to lay the foundation for spoken
language development. This is espe-
cially true if they are provided with
enhanced listening experiences. The
best predictors of verbal language
skill development are the child’s age
when full-time hearing aid use start-
ed, the degree of hearing loss and the
amount of exposure to meaningful
listening experiences. Hearing aids,
FM systems and cochlear implants are
“brain access” tools. To take advantage
of the critical period of optimal audi-
tory brain development, the ability of
the brain to perceive as much sound
as possible must be provided as soon
as possible after birth.
THE ARKANSAS FOUNDATION FOR MEDICAL CARE, INC. (AFMC) WORKS COLLABORATIVELY WITH PROVIDERS, COMMUNITY GROUPS AND OTHER STAKEHOLDERS TO PROMOTE THE QUALITY
OF CARE IN ARKANSAS THROUGH EDUCATION AND EVALUATION. FOR MORE INFORMATION ABOUT AFMC QUALITY IMPROVEMENT PROJECTS, CALL 1-877-375-5700. • AUGUST 2018
36 • THE JOURNAL OF THE ARKANSAS MEDICAL SOCIETY
VOLUME 115