Transcript Document

Overview of Behavioral and Clinical
Research at the Boys Town
National Research Hospital
Nebraska Biomedical Research
Retreat 2006
Overview of BTNRH
40,000 outpatients per year.
Clinical programs focused on
pediatrics and communication
disorders.
One of the world’s largest
communication disorders
research programs.
Hospital: 1977; Lied Center:
2004; BTNRH - West : 2006
Three Major Areas of Research
Clinical and Behavioral Studies of Human
Communication
Hereditary Communication Disorders
Auditory, Vestibular and Retinal
Neurobiology
For talks this morning, our work in genetics
has been subdivided into clinical studies
and molecular studies.
Current grant-funded Behavioral and Clinical
Research at BTNRH is focused on early
identification and remediation of hearing loss.
Infant hearing screening
Better measurement procedures
Communication development
Hearing aids and cochlear implants
Hereditary communication disorders
Infant Hearing Screening
Universal newborn hearing screening is now
mandated in Nebraska and most other states.
Screening is done using evoked potentials (EPs)
and/or oto-acoustic emissions (OAEs).
– Normal inner ears produce a faint echo or
OAE that can be recorded in the ear canal.
– OAEs reflect inner ear mechanics.
False positives can be reduced with use of new
measures of middle ear function.
Infant Hearing Screening
Norms for some EP and OAE measures were
developed at BTNRH.
Some OAE measurement and screening devices
use software developed at BTNRH.
3 BTNRH laboratories are doing research to
develop better EP, OAE and middle-ear
measurement procedures.
Clinical Sensory Physiology Lab
Michael Gorga
Goal: To gain greater insight into cochlear processing in
both normal and impaired human ears through the use of
noninvasive acoustical and electro-physiological
techniques.
Current Projects:
– Understanding sources of variability in normal cochlear
responses.
– Developing more accurate techniques for identifying and
quantifying hearing loss in infants, young children, and
patients with developmental disabilities.
– Determining whether cochlear processing in humans
differs for low and high frequencies.
Physical Acoustics Laboratory
Douglas Keefe
Goal: To better understand: (1) the inter-relationships of
the acoustic functioning of the external, middle and inner ear
in children and adults, and (2) the impact of this functioning
on the processes of hearing in both normal-hearing and
hearing-impaired listeners.
Current Projects:
– Studies of a new technique to detect middle-ear
dysfunction in infants and adults .
– Measurement of spectral and temporal processes in
human hearing using OAEs.
– Use of OAEs to monitor hearing at high frequencies.
Communication Engineering Lab
Stephen Neely
Goal: Understanding the mechanisms by which the inner
ear processes sound information.
Current Projects:
– Development of mathematical models of cochlear
mechanics that provide a correct account of the inner
ear’s ability to amplify quiet sounds.
– Development of models of auditory perception that take
into account the non-linear response of the inner ear.
– Development of software to facilitate the measurement
and analysis of otoacoustic emissions.
– Development of better software to present and record
digital audio waveforms.
Better Measurement Procedures
Behavioral tests of hearing measure the
threshold of hearing (audiogram) or speech
perception.
Measures of frequency and temporal analysis
are not used clinically because they are too
variable.
Labs working on better measurement
procedures include the first 3, plus the
Psychoacoustics Laboratory.
Psychoacoustics Laboratory
Walt Jesteadt
Goal: To understand the rules governing detection and
discrimination of simple sounds by human listeners and to
use that information to refine models of how the ear
processes sounds.
Current Projects:
– Studies of how subjects make decisions about the
sounds they hear in simple intensity resolution tasks.
– We once thought that decisions were based on the
amount of energy in specific frequency regions, but we
now know that most decisions are more complex.
Communication Development
Infant hearing screening is allowing us to identify
hearing loss at birth so that we can provide
some form of remediation.
The goal is to achieve normal communication
development.
Word learning is an important component of
communication development that we can
measure.
Communication development is obviously
closely linked to more general cognitive
development.
Infant Development Lab
Mary Pat Moeller
Goals:
– To characterize early word learning strategies of
infants with normal and impaired hearing.
– To identify perceptual, social-cognitive and linguistic
factors influencing word learning.
Current Projects
– Analysis of maternal responsiveness to words,
possible words and other vocalizations.
– Study of word learning through overhearing.
– Examination of continuity between babble and the
first word stage.
Hearing Aids and Cochlear Implants
Both technologies rely heavily on
digital signal processing.
Both require unique procedures when
working with infants and young
children, including long-term follow-up.
Infants with significant hearing loss are
fitted with a hearing aid before they are
1-year old.
BTNRH is one of the few centers with
NIH-funded research programs in both
areas. Work is underway in 3 labs.
Hearing Aid Research Laboratory
Patricia Stelmachowicz
Goal: To explore ways to optimize amplification for
infants and young children with hearing loss.
Current Projects:
– Improved hearing aid signal processing (extended
bandwidth, single microphone noise reduction, and
frequency compression/transposition).
– Structured auditory learning paradigms using high
variability training (e.g., multiple talkers) to improve
perception in noise or to accelerate the normal course
of acclimatization.
Cochlear Implant
Research Lab
Michelle Hughes
Goal: To determine whether physiological measures of
implant performance can be used to predict behavioral
measures such as judgments of pitch and loudness or
speech perception.
Current Projects:
– Physiological and behavioral measures of channel
interaction in cochlear implants.
– Clinical outcomes for individuals who were borderline
cochlear implant candidates.
– Efficacy of bilateral cochlear implants.
Auditory Perception Laboratory
Donna Neff
Goal:
To explore how more central auditory processes
such as selective attention affect the ability of adult and
child listeners to perceive sounds that are degraded,
unpredictable or otherwise non-optimal.
Current Projects:
– Use of non-speech sounds to determine pattern
recognition abilities in children and adults with normal
hearing and cochlear implants.
– Development of procedures to measure selective
auditory attention in children and adults.
Hereditary Communication Disorders
At least 50% of the occurrences of childhood
hearing loss are genetic in origin.
Identification of specific genes provides an entry
point for studies of molecular mechanisms.
BTNRH was one of the first research centers to
localize genes associated with hearing loss.
For the past 10 years, most of our research in
this area has focused on Usher syndrome, the
leading cause of deafness followed by blindness.
Center for the Study and Treatment
of Usher Syndrome
William Kimberling
Goal: To identify novel genes associated with Usher
syndrome, develop efficient methods of screening and
early diagnosis, and collaborate on clinical trials to
determine the effective treatment that would delay or
stop the progression of blindness.
Current Projects:
– Development of state-wide screening programs using
chip technology.
– Genetic and environmental factors that influence the
severity of Usher syndrome.
– Identification of novel Usher genes.
Other Areas of Interest
Expanded clinical trials in otolaryngology
and pediatrics.
Boys Town Institute for Child Health
Improvement
– Directed by Thomas Tonniges, MD
– Policy and outcome studies for children and
youth with special healthcare needs.
Behavioral Health