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Ongoing Studies > Language Development |
Longitudinal
Study of Language Development:
6 months to 7 years
The Longitudinal Study of
Language Development has two interrelated objectives. First,
we are examining early information processing skills. These
skills are the basic building blocks for children's
language, and also for their cognitive abilities, which
guide thinking about the world. Our team here at the Infancy
Studies Laboratory is examining relationships between the
perceptual information-processing measures we collect in
infancy (at 6 and 9 months) and later cognitive and language
development (from 12 months to 7 years). Second, we are
interested in looking at any differences in normal
development across and within five groups of
children: Such research will help us
to understand why children acquire language in different
ways and specifically why some children have difficulty
learning language, and if all children who have language
delays do so for the same reasons, or if there are different
reasons depending on group. Our research currently yields
primarily group data which can provide us with the first
important step towards developing an early screening test
for language-based learning disabilities. The
Predictive Value of Infant Abilities Research which aims to
predict cognitive and linguistic abilities in later
childhood based on early infant behavior implicates infant
perceptual-cognitive abilities as likely analogs for
childhood information-processing skills.
Perceptual-cognitive abilities are measured in infancy by
using tasks which assess the speed or efficiency of infants'
learning about different stimuli, and also these children's
ability to discriminate between stimuli. Many studies have
shown that these skills are informative about children's
outcomes, particularly in groups of children at high-risk
for language or cognitive problems. We are especially
interested in determining whether the rate at which infants
can process brief and rapidly successive stimuli is
predictive of language outcome. It has been shown that many
children and adults with language impairments or dyslexia
have particular problems processing rapidly presented and
brief information. Most experiments have used auditory
stimuli, but this difficulty may also be evident with visual
and tactile stimuli. It is thought that difficulty
processing rapidly presented auditory information affects
infant and children's abilities to discriminate the very
brief sounds that make up verbal language. Even if their
abilities improve with age, they may have continued
difficulties with language because the original
representations of the units of language developed in
childhood were not well formed. Once children in our
studies become 12 months-of-age, they receive an early
language inventory, and at 16 and 24 months-of-age, a
standardized early language assessment. These assessments
help us to track the child's emerging proficiency in
language and will also assist in determining which children
are at risk for later language learning
difficulties. Children
with a family history of language impairment We work with many children
born into families with a history of language processing
difficulties, dyslexia, and other language-based learning
impairments. These children are at a higher risk for
developing such problems themselves. We are interested in
monitoring their development and trying to determine which
of those children are likely to have difficulties learning
language and/or develop subsequent reading and learning
problems. In addition, we are trying to determine which
children would gain most from early intervention programs we
hope to develop. Children
who were born very low birth weight and premature
For three years, we have
been following the development of a group of very low birth
weight premature infants (<1500 grams birthweight and
< 32 weeks gestational age). Children who are born this
preterm have been found to be at an elevated risk for
language and cognitive delays. We would like to determine if
the difficulties that such children have in learning
language are from general cognitive or attentional problems,
or if they have more specific difficulties processing
rapidly presented information. In addition, a number of
children suffered subependymal and intraventricular brain
hemorrhage. We would like to determine if these children are
at heightened risk of processing problems and later language
and cognitive delays, and if the nature (extent and
location) of the brain hemorrhage relates to the specific
sorts of problems these children experience. In this way, we
can learn which areas of the developing brain support which
functions (this relationship between location and function
can be quite different in infants than in adults and even
children). Children
who had recurrent middle ear infections (otitis media)
during infancy Recurrent acute otitis
media or repeated ear infections with collection of fluid in
the middle ear (middle ear effusion) during the first year
can produce language and speech delays as a function of poor
hearing. Many children go on to have normal hearing and
normal language. However, a higher percentage of children
who have repeated episodes of otitis media subsequently are
found to have delayed language or specific language
impairment. Conversely, children with language problems are
more likely to have a history of recurrent otitis media. It
may be the case that the alteration of speech sounds caused
by such cyclic hearing changes could produce learned
deficits in the ability to process rapidly presented sounds.
In essence, the fluctuating hearing loss during the early
years may present the child with a speech signal that is
more diffuse and thus more difficult to process. This may be
particularly critical if it occurs in the first year, during
which the infant is establishing speech and language
categories. As we are following our children through age 7,
we will be able to see whether or not an early delay in
language due to repeated otitis media episodes is predictive
of school-age learning language impairments.
Ongoing
Studies >
Language Development