|
EDUCATIONAL HELPS ...
Autism Spectrum Disorders Research at the National
Institute of Mental Health
-
A publication of the The National Institute of
Mental Health (NIMH)
-
NIH Publication No. 04-4508
-
Date: 2005 (rev)
-
Approx. 16 pages when printed.
-
PDF
version
An overview that summarizes research into the causes,
diagnosis, prevention, and treatment of autism
spectrum disorders.
Autism spectrum disorders (ASD), a broad continuum of
brain illnesses that includes Asperger's
syndrome, share common genetic roots and essential
clinical and behavioral features, although they
differ in severity and age of onset. Autism, the most
severe of these pervasive developmental disorders,
typically begins in early childhood and impairs
thinking, feeling, language, and the ability to
relate to others.
From 1 to 6 in 1,000 Americans suffer from ASDs,1,2 with some
recent studies citing dramatic apparent increases in
prevalence in certain locales. Boys with the
disorders outnumber girls three or four to one.
Within the first few years of life, children with
ASDs fail to develop normal social interaction and
communication and show restricted, repetitive, or
stereotyped behaviors and interests.
Families coping with ASDs are searching for answers
about causes, diagnosis, prevention, and treatment.
The National Institute of Mental Health's (NIMH)
investment in autism-related science has quadrupled
over the past 7 years from $9.4 million in FY 1997 to
$36.2 million in FY 2002. The research is supported
through grants and contracts with investigators at
university medical centers and in the Institute's
own laboratories in Bethesda, MD. In addition, new
Institute initiatives aimed at advancing basic
knowledge of brain development and genetics hold
promise for understanding complex behavioral
disorders like autism. NIMH's autism-related
research ranges from efforts to improve awareness,
diagnosis and treatment, to studies involving brain
imaging, tissue banks, animal models, genetics,
developmental neurobiology, and neuropsychology.
Implementing the Children's Health Act of 2000
As part of the Children's Health Act of 2000,3 Congress designated the NIMH to
take the lead in expanding, intensifying, and
coordinating NIH's expanding autism research
effort, which totaled nearly $74 million in 2002.
NIMH has implemented this landmark legislation, in
collaboration with the four other Institutes
represented on the NIH Autism Coordinating Committee
(NIH/ACC): National Institute of Child Health and
Human Development (NICHD), National Institute of
Neurological Disorders and Stroke (NINDS), National
Institute on Deafness and Other Communication
Disorders (NIDCD), and National Institute of
Environmental Health Sciences (NIEHS).4
NIMH, on behalf of the Department of Health and Human
Services (DHHS), also convenes the Interagency Autism
Coordinating Committee (IACC), which serves as a
forum where Federal agencies and public members can
share information about their autism-related
activities. In addition to the NIH/ACC members, this
panel includes representatives from several DHHS
agencies and the Department of Education. The IACC
also includes four public members, family members or
guardians of people with autism or spectrum
disorders.5
Studies to Advance Autism Research and Treatment
(STAART) Network. Foremost among the Children's
Health Act's provisions is a collaborative effort
to support development of several broadly based
"Centers of Excellence in Autism Research."
In response, the five NIH/ACC Institutes have jointly
established the Studies to Advance Autism Research
and Treatment (STAART) Network. This project is
building new infrastructure for autism research by
bringing together critical masses of expertise and
resources at eight dedicated research centers across
the country. The Centers are conducting basic and
clinical research, including investigations into
causes, diagnosis, early detection, prevention, and
treatment. They include research in the fields of
developmental neurobiology, genetics, clinical
developmental psychology, and psychopharmacology.
Interdisciplinary collaborations, including the
recruitment of outstanding investigators who had
previously not worked in the autism field, are being
funded in stages over the next several years.
Grants totaling $65 million over 5 years were funded
in Fall 2002 and Spring 2003 to support STAART
Centers at the following sites:6,7
-
University of North Carolina, Chapel Hill
-
-
Yale University
-
-
University of Washington
-
-
University of California, Los Angeles
-
-
Mount Sinai Medical School
-
-
Kennedy Krieger Institute, Baltimore
-
-
Boston University
-
-
University of Rochester, New York
-
Each center is pursuing its own particular mix of
studies. For example, at the Kennedy Krieger
Institute and four collaborating area institutions, a
team of 27 researchers psychiatrists,
neuropsychologists, psychologists, speech-language
pathologists, developmental pediatricians and
neuroscientists are examining motor and communication
impairments in autism, to find out what goes wrong in
the developing brain, with an eye to early
identification and intervention. Spurred by evidence
of a serotonin abnormality in autism, investigators
are studying animals deficient in the chemical
messenger to discover its role in establishing
connections between neurons.
Among other STAART Center studies currently underway,
researchers at Yale University are examining eye
tracking in children with autism age 5-12, as well in
toddlers. They are studying how a child sees a social
situation, relative to his or her level of social
competence. Investigators there are also using
functional brain imaging to assess the effectiveness
of a computer-assisted intervention to improve facial
identification and facial expression in autism. A
study of relatives of individuals with autism and
Down syndrome at the University of North Carolina is
looking for patterns of thinking about social
situations and "executive functioning"
(planning, impulse control and reasoning) that might
provide clues to psychological characteristics shared
in common among families with these highly heritable
disorders. A brain imaging study seeks to discover
the neural roots of social and emotional processes as
well as executive functioning and
ritualistic-repetitive behaviors in adults and very
young children with autism.8
Public Input
The Children's Health Act of 2000 mandates that
the NIH make available information about its autism
activities and facilitate public feedback to the NIH.
Communications Directors, Public Liaison Officers,
and other staff from the NIH/ACC regularly engage
with representatives of autism advocacy groups to
exchange information and stay in touch via an
internet web site and a list-serve. Members of the
autism advocacy community also serve as public
participants on NIMH scientific review committees. A
searchable information clearinghouse for all NIH
autism-related activities is posted on the National
Library of Medicine's MedlinePlus Web site
(http://www.nlm.nih.gov/medlineplus/autism.html).
This links to several resources within the DHHS,
including NIMH's autism Web page
(http://www.nimh.nih.gov/healthinformation/autismmenu.cfm).
Brain Tissue and Genetics Resources
The Children's Health Act of 2000 also calls on
NIMH to take the lead in expanding a program under
which samples of tissues and genetic materials are
donated, collected, preserved, and made available for
autism research. Post-mortem brain tissue, which has
been very scarce for the study of autism, offers a
unique, high-resolution window into the inner
workings of brain cells. For example, by using
radioactive tracers on thinly sliced sections of
brain tissue, scientists can detect and pinpoint
abnormal activity of genes within cells. Only with
access to brain tissue can the underlying
neuropathology of autism be uncovered. To take
advantage of emerging opportunities for discovery in
post-mortem tissue made possible by the new molecular
methodologies, NIMH, in collaboration with the autism
community and other NIH Institutes, is stepping up
efforts to establish brain bank collections to study
autism. For example, NIMH, NINDS and NIDCD are
mounting a joint effort to develop a National Autism
Brain Bank at the Harvard Brain Tissue Resource
Center, which is primarily funded by NIMH and NINDS.
It will store and disseminate postmortem human brain
specimens for the study of autism.9
Diagnosis, Training, and Early Identification
People with ASDs show a broad range of impairment,
with great variability in clinical symptoms and
levels of functioning. For example, some people with
autism have normal intelligence and develop good
basic language skills, while others lag
intellectually and develop little or no language. A
common diagnostic scheme for assessing the complex
social and communication deficits that constitute key
features of the disorder has been a critical
prerequisite to scientific progress.
NIMH has supported research that has raised the
quality and standardization of screening and
diagnosis in autism. Standard diagnostic interviews
and observational methods developed through this
research have become a national and international
"gold standard," ensuring that what is
diagnosed in one research center is comparable to
that diagnosed in another. The Institute funds a
series of annual workshops for training researchers
in the use of these tools, and is funding further
investigation of measurement tools.10,11
NIMH also supports research aimed at improving early
diagnosis of autism. Institute-supported studies have
demonstrated that a reliable diagnosis of autism
spectrum can be made at age 2.12 Yet, the age of onset remains
elusive. Some children seem to develop normally for a
couple of years and then regress; for example, they
may lose language skills after developing a small
vocabulary. Others may be affected from birth, but in
such subtle ways that diagnosis is delayed. Earlier
identification of children destined to develop
symptoms could hold clues to the underlying
neuropathology and would also facilitate early
intervention. NIMH is funding studies that focus on
young children at heightened risk for the disorder,
such as younger siblings of children with autism.13,14,15
Brain Imaging
Non-invasive brain imaging techniques, such as MRI
(magnetic resonance imaging), offer great potential
for advancing understanding of the neural basis of
emotional and intellectual deficits in autism and
other childhood neuropsychiatric disorders. However,
scientists currently have little data on normal brain
function and development to compare with data from
individuals with autism. Such norms have been lacking
for brain imaging studies, leading to non-comparable
findings and excessive duplication in scanning
control subjects. Therefore, NIMH is co-sponsoring,
with NICHD, NIDA and NINDS, a $28 million initiative
that is using aMRI (anatomic magnetic resonance
imaging), DTI (diffusion tensor imaging), and MRS
(magnetic resonance spectroscopy) to create the
world's first such large-scale database on normal
brain development in children.16
The NIH MRI Study of Normal Brain Development is
cataloging the structural development of the brain,
by age and sex, with seven major research centers
scanning more than 500 infants, children, and
adolescents. Children age 5 and older are being
followed up with additional scans and clinical and
behavioral reassessments at 2-year intervals. Younger
children are being re-scanned at more frequent
intervals—3-12 months to capture more rapid
brain maturational changes occurring at these ages.
This study will permit the normal growth curves of
brain structures to be charted, revealing the
development of circuitry for language, thinking, and
other functions. Individual brains differ enough that
only broad generalizations can be made from
comparisons of different individuals at different
ages. But following the same brains as they mature
allows scientists a much more detailed view of
developmental changes. By comparing scans of children
with neuropsychiatric disorders with this normative
data, researchers will be able to determine the
timing and developmental course of brain structural
changes in childhood disorders. These databases,
being developed by an NIMH-funded data analysis
center, will ultimately facilitate early diagnosis
and differentiation of various forms of autism. It
will also speed the development of targeted
treatments and evaluations of their effects.
The promise of such a normative brain database for
turning up clues about childhood brain disorders was
recently illustrated in a similar, but smaller-scale,
NIMH intramural study.17 In
this first longitudinal structural MRI study to track
individual children's developing brains, the
researchers were surprised to discover a second wave
of overproduction of gray matter (neurons) just prior
to puberty. Possibly related to the influence of
surging sex hormones, this thickening peaks at around
age 11 in girls, 12 in boys, after which the gray
matter actually thins some. Prior to this study,
scientists had thought that the brain overproduced
gray matter for a brief period in early development
(in the womb and for about the first 18 months of
life) and then underwent just one bout of pruning.
The gray matter growth spurt predominates in the
frontal lobe, the seat of executive functions. This
type of normative data will help researchers contrast
typical growth with that in autism spectrum
disorders. A wave of abnormal brain enlargement seen
in MRI studies of young children with autism follows
a back-to-front pattern, similar to a wave of
abnormal gray matter loss seen in childhood onset
schizophrenia. This may suggest a process in which
the timing and trajectory of various abnormalities
parallels clinical outcome.18,38 In other
brain imaging studies, researchers using MRI and MRS
are searching for brain anatomical and biochemical
abnormalities that may underlie impaired social
communication in children with autism. One fMRI study
is looking for malfunctioning brain circuits
associated with impaired thinking about human
relationships, a problem seen in autism. While in the
scanner, subjects view animated cartoons designed to
challenge their ability to understand a social
situation. High-functioning individuals with autism
are being scanned to sort out the neural circuitry of
social versus mechanical knowledge.19,20
Yet another series of MRI studies is pinpointing
brain structural abnormalities associated with the
severity of attention deficits in people with
autism.21 For example, the
researchers have shown that decreased volume in an
area of the brain's parietal lobe correlates with
the degree of behavioral impairment in detecting
stimuli located outside a principal focus of visual
attention.
A project at the University of North Carolina has
been assessing the relation between brain anatomy and
autism through MRI scans of very young children with
autism.22 The aim is to get a
better picture of the development and timing of the
brain enlargement that occurs in autism between 18
and 35 months. To relate these findings to another
developmental disorder of known origin, the
researchers have joined forces with colleagues at
Stanford University to similarly follow the brain
development of children with Fragile X syndrome.23,24 These
studies will illuminate genetic and environmental
factors that influence normal and abnormal brain
development and may help to clarify subtypes of
autism.
Animal Models
Studies in monkeys hold great potential for
understanding autism, since their brains resemble
those of humans thus offering valuable clues. For
example, NIMH-funded investigators are continuing to
examine monkeys in which early injury to the
brain's limbic system, or emotional hub,
interfered with the establishment of social and
emotional bonds.25 Experiments
in monkeys by NIMH intramural scientists found that
loss in infancy of two key limbic structures, the
amygdala and hippocampus, results in social and
emotional abnormalities strikingly similar to autism,
in both nature and time course, by 6 months of age.
The monkeys with brain lesions, like some autistic
children, showed an absence of social interactions,
lack of normal facial expressions and body language,
and stereotyped behaviors. Also as in autism, the
problems emerged only after early infancy and
remained permanent. Other monkeys in which a lower
part of the temporal lobe was removed developed
milder symptoms that substantially abated as they
grew older. This study, combined with clinical
findings, point to the limbic system structures as
likely sites of damage in autism.26 Such behavioral and neuroanatomical
research may help to pinpoint brain circuit
abnormalities in autism and ultimately lead to
intervention strategies. Findings relevant to autism
may also emerge from planned studies of proteins in
the animal brain.
Assuming there is a developmental abnormality in
autism, due to a gene defect or gene/ environment
interaction, some genes are likely to turn on too
much or too little or in the wrong place. This may
interfere with the migration and wiring of embryonic
brain cells during early development, or with the way
cells function. In collaboration with other NIH
Institutes and the private sector, NIMH is mounting
efforts to expand the set of available tools for
discovering such molecular mistakes.
For example, studies in mice are identifying the
neural basis of complex behaviors. The mouse has
become a critical model in studying human disease
because scientists have access to many specially bred
strains each expressing distinctive physiological and
behavioral characteristics and know an enormous
amount about mouse genetics. Rapidly-evolving
technologies now make it possible to insert, knock
out, or mutate mouse genes, quickly breed a
generation that expresses the change, and then see
how it affects behavior. When autism-linked genes are
discovered, they will be inserted and expressed in
mice to find out what they do at the molecular,
cellular, and behavioral levels. Researchers will be
able to track a wiring abnormality, a cell migration
abnormality, or other anomaly that may lead to
symptoms in humans.
Clinical Genetics
While it is known that heredity plays a major role in
complex behavioral disorders like autism, the
identification of specific genes that confer
vulnerability to such disorders has proven extremely
difficult. Detecting multiple genes, each
contributing only a small effect, requires large
sample sizes and powerful technologies that can
associate genetic variations with disease and
pinpoint candidate genes. And even after human
disease vulnerability genes are found, sophisticated
techniques will be needed to find out what turns them
on, what brain components they code for, and how they
affect behavior. Although by no means assured, the
prospect of acquiring such molecular knowledge holds
great hope for the engineering of new therapies.
Evidence suggests that some family members of people
with autism may share with them milder, but
qualitatively similar, behavioral characteristics of
autism.27 For example, they may
have mild social, language or reading problems. A
multi-site team of NIMH-supported investigators has
been studying such families to characterize these
behavioral traits in hopes of discovering sites in
the genome associated with them. In the latest phase
of these studies, neuropsychological characteristics
of relatives of individuals with autism and autism
spectrum will be compared with those of people with
injuries to brain areas implicated in autism, such as
the amygdala and frontal cortex. Patterns of
co-occurrence of the characteristics will be examined
in individuals and families.28
Four previously undetected chromosomal sites strongly
linked to autism have been discovered by the largest
and methodologically most sophisticated genome-wide
screens to date, funded, in part, by NIMH. Two
studies, led by investigators at Columbia University
and the University of Oxford, add regions on
chromosomes 2, 5, 8, and 17 to a growing list of
areas likely harboring autism-predisposing genes.
They also add to previous evidence implicating areas
on chromosomes 7, 16, and 19.29,30
Although one chromosomal region, 7q, had turned up
consistently in such screens, no specific candidate
gene there had yet been pinpointed until NIMH-funded
researchers, led by a team at the University of Iowa,
discovered that variants of a particular gene in the
7q region, expressed in human thalamus, may be
associated with autism susceptibility.31 It is a member of a family of genes
that influences brain development.
To increase the likelihood of finding genes for
autism, researchers are increasing the statistical
power of human data sets. One genome-wide screen of
autism vulnerability genes in 110 families showed
suggestive evidence for linkage to ASD on several
chromosomes. In a follow-up analysis, the researchers
increased the sample size threefold while holding the
study design constant, so that 345 families (each
with at least two siblings affected with autism or
ASD), were included. The most significant findings
were on chromosome 17q conspicuously near the gene
that codes for the serotonin transporter and on 5p.
Analyses from this largest data set studied to date
implicate brain serotonin systems in autism. This
finding is congruent with those from other studies
which show evidence of elevated blood serotonin
levels both in patients with autism and in their
unaffected first-degree relatives. Studies also show
that drugs that selectively target 5-HTT can
ameliorate some autism-related symptoms.
Serotonin-related neural circuits may thus provide
targets for new drug development.32
Continued progress in molecular genetic studies of
autism will require very large sample sizes, and the
pooling of ever larger numbers of families. In
addition, future studies likely will require the
identification and characterization of autism-related
traits correlated with liability to produce disease.
NIMH is supporting efforts to reach out to families
to build a library of DNA samples and clinical data
that can be broadly distributed to researchers
through the NIMH Human Genetics Initiative
http://www.nimhgenetics.org/. For example, in
March of 2002 NIMH announced the awarding of a grant
totaling more than $6 million, over 5 years, to
researchers at the University of California, Los
Angeles, for a major expansion of the Autism Genetic
Resource Exchange (AGRE) gene bank, a collaborative
effort with the citizens group Cure Autism Now (CAN).
The goal is to add 300 more families to this
resource, which conducts 2-hour in-home screenings of
families that have more than one member diagnosed
with autism, PDD or Asperger's syndrome.33 A similarly ambitious $5 million
public/private collaboration between the National
Alliance for Autism Research (NAAR) and NIMH, NICHD,
NINDS, NIDCD was recently announced. The NAAR Autism
Genome Project is also focused on finding genes
associated with the autism spectrum disorders.
Using the AGRE data set, researchers at Rutgers
University recently discovered a strong association
between a gene in the 7q region and autism. Among 167
affected families, children with autism were twice as
likely as unaffected children to have inherited a
particular variant of a gene called ENGRAILED 2. The
team is now attempting to replicate the finding in a
much larger sample, using data sets funded in part by
NIMH.34
Developmental Neurobiology
To function properly, the brain must be wired
correctly during critical periods in early
development. Mistakes in this process, resulting in
circuitry gone awry, are hypothesized to occur in
neuro-developmental disorders like autism.
NIMH-funded researchers recently developed a way to
discover the normal wiring diagram of the mammalian
brain.35 The technique, a type
of "gene trap," provides a shortcut for
identifying from among the tangled trillions of
neural connections just the machinery involved in
brain wiring. The trick for finding the needle in a
haystack: attach a molecular tag to the needle.
Through genetic engineering, lines of mice are bred
to express telltale mutations. Brain neurons
harboring particular wiring molecules are revealed by
a blue tint, while their tentacle-like extensions, or
axons, are colored purple.
By breeding strains of mice in which particular genes
are knocked-out, other Institute-funded researchers
have been discovering the molecular machinery of the
guidance systems used by such migrating embryonic
neurons. When they knocked-out the cell's
antennae for receiving vital signals from guidance
chemicals, the tentacle-like axons failed to make the
proper connections.36
After reviewing evidence pointing to abnormal brain
development in autism, researchers at the University
of California, supported in part by NIMH, have
proposed that the disorder stems from mechanisms gone
awry that normally regulate brain growth. This
"growth dysregulation hypothesis" holds
that the anatomical abnormalities seen in autism are
caused by genetic defects in brain growth factors.
Due to abnormal timing in the starting and stopping
of growth in neurons and supportive tissue, there is
premature overgrowth in some brain structures and
reduced growth or excessive cell loss in others, the
researchers suggest.37 Although
the head size and brains of children with autism are
slightly smaller than normal at birth, they undergo a
spurt of excessive brain growth soon thereafter.
Increased head circumference by the end of the first
year predicted an enlarged cerebrum and cerebellum by
2 to 5 years of age. Sudden, rapid head growth in an
infant may signal for risk of developing autism, the
researchers propose.38
Neuropsychology
NIMH-supported neuropsychologists are dissecting the
nature of cognitive deficits in autism and related
disorders. Since identification of the syndrome more
than 60 years ago, clinicians and researchers have
been intrigued with the uneven ability profiles of
individuals with autism. While many affected
individuals show generalized deficits, many also show
areas of intact functioning. The nature of these
deficits and strengths, their relationship to
clinical symptoms, implications for treatment, and
implications for underlying neurobiology, are the
focus of these studies.
Adults with autism show more executive function
deficits than those with other developmental
disabilities. Executive functions include the ability
to plan ahead, work toward a goal and to hold a
mental representation "on-line" in working
memory. To see if such deficits might underlie the
syndrome, NIMH-funded researchers at the University
of Denver compared the performance of preschoolers
with autism with age-matched controls on eight
executive function tasks. Surprisingly, the children
with autism performed as well or better than the
control group, suggesting that developmental lags in
this area are not specific to autism. A second study
that tracked children's progress in performing a
spatial reversal task over a year found no evidence
that children with autism were growing into an
executive deficit over time. Rather, the children
without autism seemed to be growing out of a deficit.
The two groups seemed to be on diverging
developmental trajectories. These results cast doubt
on the notion that autism stems exclusively from
executive function deficits.39
Co-occurring Disorders
In addition to cognitive impairments, individuals
with autism and other ASDs often suffer from multiple
and severe mental and emotional problems. These
include impulse-control disorders,
obsessive-compulsive disorder, mood and anxiety
disorders, mental retardation, and genetic disorders
such as Fragile X. Such co-existing problems start
early in life, are chronic, and account for a
substantial portion of outpatient, inpatient, and
residential services. They present immense challenges
to clinicians and families, and the complexity of the
psychopathology presents enormous research
challenges. NIMH is developing and testing treatment
and rehabilitative interventions for such
co-occurring psychopathology.40
Individuals with autism may also have co-occurring
seizures and tuberous sclerosis, a genetic disorder
that causes benign tumors to form in many different
organs, primarily in the brain, eyes, heart, kidney,
skin, and lungs.
A key set of proteins involved in synaptic plasticity
and neuronal growth, some of them likely implicated
in ASDs, has been discovered by an NIMH-funded
scientific team. Researchers at the University of
Pennsylvania and the University of Illinois developed
a new technique that revealed, in living neurons, a
swath of secondary damage caused by the primary
protein defect in Fragile X syndrome, the most common
inherited form of mental retardation. Mental
retardation is common in people with autism, and the
new findings suggest that ASDs too may be traceable
to this protein pathway. Gene knockout mice modeling
the protein defect showed abnormalities in the
distribution and quantities of some of the affected
secondary proteins and the genetic material that
makes them. A melding of genomics and proteomics, the
new method, called Antibody Positioned RNA
Amplification (APRA), can be applied in similar
studies of other systems and cells.41
Defective fragile X mental retardation protein (FMRP)
can have devastating effects because as an "RNA
binding protein" it influences many other
proteins in critical brain centers, like the
hippocampus, a memory hub. FMRP regulates the
synthesis and transport of a bevy of heretofore
unknown associated proteins. Like a dispatcher in a
truck depot, FMRP manages the shuttling of these
"cargo proteins" from the cell's
nucleus to supply the needs of its working parts, or
cytoplasm. Much of the cargo turns out to be the
genetic material (RNA) that makes proteins vital to
synaptic maturation and communication between neurons
which breaks down if the 'dispatcher'
can't do its job.
To discover FMRP's cargo proteins in cultured
mouse hippocampal neurons, the researchers devised an
intricate methodology (APRA) that takes advantage of
the specific affinity that antibodies and short
strands of genetic material have for particular genes
and proteins. They joined an antibody that binds to
FMRP with genetic material that, in turn, binds to
genes associated with FMRP. The antibody positions
the molecular probe close to the FMRP cargo so that
it can be detected. Among genes expressed in the
human brain, about 60 percent detected by the probe
were directly associated with FMRP again, many
involved in synaptic plasticity and neuronal
maturation.
Since some people with Fragile X syndrome show
autistic behavior, the researchers suspected that
some FMRP cargo proteins might also be associated
with autism. Among the 81 proteins, 15 mapped to the
same chromosomal locations as candidate autism genes.
Mutations in some of the genes that code for these
proteins may contribute to autism and other disorders
characterized by autistic-like social impairment and
stereotyped behavior.
Treatment
Both psychosocial and pharmacological interventions
can improve the behavioral and cognitive functioning
of individuals with ASDs.42 The
increasing use of psychotropic medications to treat
symptoms of autism and other childhood-onset
psychiatric disorders has spotlighted an urgent need
for more studies of such drugs in children. To meet
this need, NIMH established a network of Research
Units on Pediatric Psychopharmacology (RUPPs) in 1997
that combined expertise in psychopharmacology and
psychiatry at several research sites. The network was
expanded to include psychosocial interventions with
the funding of additional network projects called the
RUPP-PI (Research Units on Pediatric
Psychopharmacology and Psychosocial Interventions)
network. The RUPP and RUPP-PI networks are intended
to become a national resource that will expedite
clinical trials in children.43,44,45 They include five groups
specifically funded to evaluate treatments for
autism. Studies are examining dose range and regimen
of medications, and their mechanisms of action,
safety, efficacy, and effects on cognition, behavior,
and development. The RUPP network is nearing
completion of a study examining the efficacy of
methylphenidate for treating hyperactivity and
impulsivity in children and adolescents with a
variety of behavioral disorders. In one recent study,
risperidone, one of a newer class of anti-psychotic
medications, was successful and well tolerated for
the treatment of serious behavioral disturbance in
children with autism aged 5-17.46
The RUPP-PI network has launched a multi-site study
investigating the effect of combined parent training
and medication treatment on disruptive behavior in
children with autism spectrum disorders. The study
will test whether adding a program to teach parents
behavior management techniques to a regimen of
risperidone will add to treatment response and/or
maintain treatment effects after discontinuation of
the medication.47,48, 49
Among other studies of psychosocial treatments in
autism, two NIMH-funded research teams are evaluating
parent training interventions that are tailored to
the particular characteristics of the child and
family. The investigators have demonstrated that an
individualized approach enhances the effectiveness of
their Pivotal Response Model, and that this, in turn,
leads to positive changes in parents' confidence
and feelings of empowerment.50,51,52 The investigators are continuing
their line of research on interventions development
with a study investigating the efficacy of visual
augmentation strategies for teaching communication
skills to nonverbal children with autism.53,54,55
The NIH Autism Coordinating Committee (NIH/ACC)
coordinates efforts of NIMH, NICHD, NINDS, NIDCD, and
NIEHS to facilitate research on interventions for
individuals with autism and autism spectrum
disorders. In November 2000, six grants were funded
in response to an RFA (Request for Applications)56 for innovative methods and
feasibility studies. These projects included
behavioral and pharmacological treatments and are
nearing completion. The STAART Centers funded in 2002
and 2003 (described above) include eight treatment
projects that are in development or underway. Foci of
the intervention projects include efficacy of early
interventions, efficacy of treatments for social
deficits, efficacy trials for pharmacotherapy, and
understanding the variability of response to
treatments. Through these and other initiatives, the
Institutes hope to encourage multi-disciplinary
partnerships to develop and improve treatments for
individuals with autism spectrum disorders.
The NIH/ACC sponsored a workshop "Research on
Psychosocial and Behavioral Interventions in Autism:
Confronting the Methodological Challenges" in
September 2002.37 The purpose of the meeting was to
review the state-of-the-science with regard to
psychosocial, behavioral, and educational
interventions for children with autism; to examine
the barriers to progress in the field; and to discuss
potential strategies for overcoming the barriers. An
outcome of the meeting was the formation of ongoing
working groups of scientists focusing on methodology
and design issues.
Services
As part of its initiative on Child and Adolescent
Interdisciplinary Research Networks, NIMH awarded a
grant in FY 2003 to the University of
California-Davis, "Enhancing Mental Health
Services to Children with Autism." This
innovative effort will create, for the first time, a
formal, interdisciplinary research network of faculty
and community representatives focused on an
understudied population, children with autism and
their families in rural communities. The network will
review barriers and develop guidelines for
implementing telehealth technologies such as clinical
telemedicine, distance learning, and information
distribution for the delivery of high quality,
empirically supported, and coordinated mental health
services.
NIH Collaboration
NIMH supports research on autism in collaboration
with the National Institute of Child Health and Human
Development, the National Institute of Neurological
Disorders and Stroke, the National Institute on
Deafness and Other Communication Disorders, and the
National Institute of Environmental Health Sciences.
The Broad NIMH Research Program
NIMH supports and conducts a broad-based,
multidisciplinary program of scientific inquiry aimed
at improving the diagnosis, prevention, and treatment
of mental disorders in people of all ages.
Increasingly the public, as well as health care
professionals, are recognizing these disorders as
real and treatable medical illnesses of the brain.
Still, there is a need for more research that
examines in greater depth the relationships among
genetic, behavioral, developmental, social, and other
factors to find the causes of these illnesses. NIMH
is meeting this need through a series of research
initiatives.
NIMH Human Genetics Initiative
This project has compiled a large repository of
clinical information and DNA obtained from families
affected by schizophrenia, bipolar disorder, autism,
Alzheimer's disease, and other mental disorders.
Qualified scientists are given access to these data
and genetic materials in order to characterize the
genetic bases of mental disorders.
Neuroinformatics: Human Brain Project
This Federal effort is using state-of-the-art
computer science technologies to organize the immense
amount of data being generated through neuroscience
and related disciplines, and to make this information
readily accessible through the World Wide Web for
simultaneous study by interested investigators.
Because the scope of the Human Brain Project extends
to all facets of brain and behavioral research and
includes a range of technology sciences, this
initiative is sponsored, in a coordinated fashion, by
15 Federal organizations across four Federal
agencies: the National Institutes of Health, National
Aeronautics and Space Administration, National
Science Foundation, and U.S. Department of Energy.
Prevention Research Initiative
Prevention research can be broadly characterized as
seeking to understand the development and expression
of mental illness throughout the course of life so
that appropriate interventions can be designed and
applied in order to prevent mental disorders and
promote mental health. Advances in biomedical,
behavioral, and cognitive sciences led NIMH to
formulate a plan, Priorities for Prevention Research
at NIMH, which marries these sciences to prevention
efforts. Focusing on the expansion of prevention
research to include the prevention of relapse,
disability, and co-occurring conditions, the plan
provides a blueprint for NIMH prevention research in
the years to come.
Key Areas of NIMH Research
In total, NIMH supports more than 2,000 research
grants and contracts at universities and other
institutions across the nation and overseas. It
also conducts basic research and clinical studies
at its own facilities on the National Institutes of
Health campus in Bethesda, MD, and elsewhere. Key
areas of NIMH research include:
-
basic research on behavior, emotion, and
cognition to provide a knowledge base for a
better understanding of mental illnesses;
-
-
basic sciences, including cellular and molecular
biology, developmental neurobiology,
neurochemistry, neurogenetics, and
neuropharmacology, to provide essential
information about the anatomical and chemical
basis of brain function and brain disorders;
-
-
neuroscience and behavioral aspects of acquired
immune deficiency syndrome (AIDS) and behavioral
strategies to reduce the spread of human
immunodeficiency virus (HIV);
-
-
clinical trials to test interventions to treat,
prevent, and reduce the frequency of mental
disorders and their disabling consequences;
-
-
mental health services research, including mental
health economics and improved methods of services
delivery;
-
-
co-occurrence among mental disorders and with
substance abuse and other medical conditions,
such as depression and heart disease;
-
-
the prevalence of mental disorders;
-
-
risk factors for mental disorders and protective
factors against them;
-
-
suicide, suicidal behavior, risk and protective
factors, and preventive interventions;
differences in mental health and mental illness
among special populations;
-
-
children and adolescents who suffer from or who
are at risk for serious mental disorders and
learning disabilities;
-
-
aging and mental health, including the impact of
caregiving;
-
-
responses to terrorist acts and major traumatic
events; and
-
-
psychotherapies and pharmacotherapies for
specific disorders.
For More Information
The NIMH Office of Communications carries out
educational activities, such as the Real Men Real
Depression campaign
http://menanddepression.nimh.nih.gov, and
publishes and distributes research reports, press
releases, fact sheets, and informational materials
intended for researchers, health care providers, and
the general public. All of these materials, and this
fact sheet, are in the public domain and may be
copied or reproduced without permission from the
Institute, although citation of NIMH as the source is
appreciated. Materials may be downloaded directly
from the NIMH Web site, or hard copies may be ordered
through the mail.
About NIMH
Visit the following link for more information about
NIMH.
References
1Yeargin-Allsopp M, Rice C,
Karapurkar T, Doernberg N, Boyle C, Murphy C.
Prevalence of Autism in a US Metropolitan Area. Journal of the American Medical
Association, 2003: 289 (1): 49-55.
2Yeargin-Allsopp M. Past and
future perspectives in autism epidemiology. Molecular Psychiatry, 2002; 7:
S9-S11.
3Children's Health Act of
2000, Public Law 106-10.
http://ffrwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=106_
cong_public_laws&docid=f:publ310.106.pdfhttp://ffrwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=106_
cong_public_laws&docid=f:publ310.106.pdf
4http://www.nimh.nih.gov/autismiacc/nihacc.cfm
5http://www.nimh.nih.gov/autismiacc/other.cfm
6http://www.nimh.nih.gov/autismiacc/other.cfm
7http://www.nimh.nih.gov/press/prautismcenters.cfm
8http://www.nimh.nih.gov/autismiacc/staart.cfm
9Benes F. A national resource for
postmortem brain research. Grant No. IR24MH068855-01.
In progress.
10Lord C. Training/research
diagnosis/autism spectrum disorders. Grant No.
5R25MH067723-01. In progress.
11Lord C. Validity of diagnostic
measures for autism spectrum. Grant No.
5R01MH066496-02. In progress.
12Stone WL, Coonrod EE, Ousley
OY. Screening tool for autism in two-year-olds
(STAT): development and preliminary data. Journal of Autism and Developmental
Disorders, 2000; 30(6): 607-12.
13Ozonoff S. Infants at risk of
autism: a longitudinal study. Grant No.
1R01MH068398-01. In progress.
14Landa R. Early detection,
intervention and neurobiology in autism. Grant No.
1U54MH066417-01A10002. In progress.
15Sigman M. Infants at risk of
autism: a longitudinal study. Grant No.
1U54MH068172-010001. In progress.
16Pediatric Study Centers (PSC)
for a MRI Study of Normal Brain Development.
http://grants.nih.gov/grants/guide/notice-files/not98-114.html
17Giedd JN, Blumenthal J,
Jeffries NO, Castellanos FX, Liu H, Zijdenbos A, Paus
T, Evans AC, Rapoport JL. Brain development during
childhood and adolescence: a longitudinal MRI study.
Nature Neuroscience, 1999;
2(10): 861-63.
18Rapoport JL, Giedd JN,
Blumenthal J, Hamburger S, Jeffries N, Fernandez T,
Nicolson R, Bedwell J, Lenane M, Zijendos A, Paus T,
Evans A. Progressive cortical change during
adolescence in childhood-onset schizophrenia. A
longitudinal magnetic resonance imaging study. Archives of General Psychiatry,
1999; 56(7): 649-54.
19Martin A, Giedd J. Brain
imaging of childhood onset psychiatric disorders,
endocrine disorders and healthy controls. NIH
Protocol No. 89-M-0006. In progress.
http://clinicalstudies.info.nih.gov/cgi/wais/bold032001.pl?A_1989-M-0006.html@autism
20Martin A, Weisberg J. Neural
foundations for understanding social and mechanical
concepts, Cognitive
Neuropsychopharmacology. 2003, 20 (3/4/5/6):
575-87.
21Courchesne E. Anatomy and
function correlates of cognition in autism. Grant No.
5R01MH36840-18. In progress.
22Piven J. Brain development in
developmental disorders. Grant No. 5R01MH061696-05.
In progress.
23Reiss AL. Longitudinal MRI
study of brain development in Fragile X. Grant No.
5R01MH064708-02. In progress.
24Piven J. Longitudinal MRI
study of brain development in Fragile X, 5. Grant No.
5R01MH064580-02. In progress.
25Bachevalier J. Development of
medial temporal lobe functions. Grant No.
R01MH58846-03. In progress.
26Bachevalier J, Malkova L,
Mishkin M. Effects of selective neonatal temporal
lobe lesions on socioemotional behavior in infant
rhesus monkeys. Behavioral
Neuroscience, 2001, 115 (3): 545-59.
27Piven J, Palmer P, Jacobi D,
Childress D, Arndt S. Broader autism phenotype:
evidence from a family history study of
multiple-incidence autism families. American Journal of Psychiatry, 1997;
154(2): 185-90.
28Piven J. Gene-brain-behavior
relationships in Autism. Grant No. 5U54MH066418-02.
In progress.
29International Molecular
Genetic Study of Autism Consortium. A genomewide
screen for autism: strong evidence for linkage to
chromosomes 2q, 7q, and 16p.
American Journal of Human Genetics, 2001, 69:
570-81.
30Liu J, Nyholt D, Magnussen P,
Parano E, Pavone P, Geschwind D, Lord C, Iversen P,
Hoh J. the Autism Genetic Resource Exchange
Consortium, Ott J, Gilliam C. A genomewide screen for
autism susceptibility loci.
American Journal of Human Genetics, 2001, 69:
327-40.
31Wassink TH, Piven J, Vieland
VJ, Huang J, Swiderski RE, Pietila J, Braun T, Beck
G, Folstein SE, Haines JL, Sheffield VC. Evidence
supporting WNT2 as an autism susceptibility gene. American Journal of Medical
Genetics, May 17, 2001.
32Yonan AL, Alarcon M, Cheng R,
Magnusson PKE, Spence SJ, Palmer AA, Grunn A, Juo
SHH, Terwilliger J, Liu J, Cantor RM, Geschwind DH,
Gilliam TC. A genomewide screen of 345 families for
autism-susceptibility loci.
American Journal of Human Genetics, 73: 886-97,
2003.
http://www3.interscience.wiley.com/cgi-bin/issuetoc?ID=77002064
33Geschwind D. Genomewide search
autism susceptibility loci supplement. Grant No.
3R01MH064547-02S1. In progress.
34Brzustowicz L. Genetic
Components of Autism Spectrum Disorders. Grant No.
1R01MH070366-01. In progress.
35Leighton PA, Mitchell KJ,
Goodrich LV, Lu X, Pinson K, Scherz P, Skarnes WC,
Tessier-Lavigne M. Defining brain wiring patterns and
mechanisms through gene trapping in mice. Nature, 2001; 410(6825): 174-79.
36Giger RJ, Cloutier JF, Sahay
A, Prinjha RK, Levengood DV, Moore SE, Pickering S,
Simmons D, Rastan S, Walsh FS, Kolodkin AL, Ginty DD,
Geppert M. Neuropilin-2 is required in vivo for
selective axon guidance responses to secreted
semaphorins. Neuron, 2000;
25(1): 29-41.
37Akshoomoff N, Pierce K,
Courchesne E. The Neurobiological basis of autism
from a developmental perspective. Development and Psychopathology, 2002,
14: 613-634.
38Courchesne E, Carper R,
Akshoomoff N. Evidence of Brain Overgrowth in the
first year of life in autism.
JAMA, 2003, 290(3): 337-344.
39Griffith EM, Pennington BF,
Wehner EA, Rogers SJ. Executive Functions in Young
Children with Autism. Child
Development, l999, 70 (4): 817-832.
40Volkmar F. The Social
Neuroscience of Autism and Related Disorders. Grant
No. 5U54MH066494-02. In progress.
41Miyashiro KY, Beckel-Mitchener
A, Becker KG, Barret T, Liu L, Carbonetto S, Weiler
IJ, Greenough WT, Eberwine J. RNA cargoes associating
with FMRP reveal deficits in cellular functioning in
Fmr1 null mice. Neuron,
2003, 37(3): 417-431.
42Bristol MM, Cohen DJ, Costello
EJ, Denckla M, Eckberg TJ, Kallen R, Kraemer HC, Lord
C, Maurer R, McIlvane WJ, Minshew N, Sigman M, Spence
MA. State of the science in autism: report to the
National Institutes Health.
Journal of Autism and Developmental Disorders,
1996; 26(2): 121-54.
43Greenhill LL, Vitiello B,
Abikoff H, Levine J, March JS, Riddle MA, Capasso L,
Cooper TB, Davies M, Fisher P, Findling RL, Fried J,
Labellarte MJ, McCracken JT, McMahon D, Robinson J,
Skrobala A, Scahill L, Varipatis E, Walkup JT, Zito
JM. Developing methodologies for monitoring long-term
safety of psychotropic medications in children:
Report on the NIMH conference, September 25, 2000.
Journal of the American Academy
of Child & Adolescent Psychiatry, 2003;
42(6): 625-26.
44McDougle CJ, Scahill L,
McCracken JT, Aman MG, Tierney E, Arnold E, Freeman
BJ, Marin A, McGough JJ, Cronin P, Posey DJ, Riddle
MA, Ritz L, Swiezy NB, Vitiello B, Bolkmar FR,
Botolato NA, Walson P. Research Units on Pediatric
Psychopharmacology (RUPP) Autism Network: Background
and rationale for an initial controlled study of
risperidone, Child & Adolescent Psychiatric
Clinics of North America, 2000; 9(1): 201-24.
45Arnold LE, Aman MG, Martin A,
Collier-Crespin A, Vitiello B, Tierney E, Asarnow R,
Bell-Bradshaw F, Freeman BJ, Gates-Ulanet P, Klin A,
McCracken JT, McDougle CJ, McGough JJ, Posey DJ,
Scahill L, Swiezy NB, Ritz L, Volkmar F. Assessment
in multisite randomized clinical trials of patients
with autistic disorder: The Autism RUPP Network. Journal of Autism & Developmental
Disorders, 2000; 30(2): 99-111.
46McCracken JT, McGough J, Shah
B, Cronin P, Hong D, Aman MG, Arnold E, Lindsay R,
Nash P, Hollway J, McDougle CJ, Posey D, Swiezy N,
Kohn A, Scahill L, Martin A, Koenig K, Volkmar F,
Carroll D, Lancor A, Tierney E, Ghuman J, Gonzalez
NM, Grados M, Vitiello B, Ritz L, Davies M, Robinson
J, McMahon D. Risperidone in children with autism and
serious behavioral problems. New
England Journal of Medicine, 2002; 347(5):
314-21.
47Aman, M. The OSU RUPP-PI
Project. Grant No. U10MH66768. In progress.
48McDougle, C. RUPP-PI at
Indiana University School of Medicine. Grant No.
U10MH66766. In progress.
49Scahill, L. RUPP-PI Program at
Yale University. Grant No. U10MH66764. In progress.
50Koegel LK, Koegel RL, Jarrower
JK, Carter CM. Pivotal response intervention I:
Overview of approach. Journal of
the Association for the Severely Handicapped,
1999; 24: 174-85.
51Koegel LK, Koegel RL, Shoshan
Y, McNerney E. Pivotal response intervention II:
Preliminary long-term outcome data. Journal of the Association for Persons with
Severe Handicaps, 1999; 24:186-98.
52Koegel RL, Brookman L, Koegel
LK. Autism: Pivotal response intervention and parent
empowerment. Trends in
Evidence-Based Neuropsychiatry, 2003; 5(1):
53-61.
53Koegel R. Research in autism:
Parent intervention. Grant No. R10MH28210-22. In
progress.
54Schreibman L. Research in
autism: Parent Intervention. Grant No. R10MH39434-14.
In progress.
55Whalen C, Schreibman L. Joint
attention training for children with autism using
behaviour modification procedures. The Journal of Child Psychology and
Psychiatry, 2003; 44, 456-468.
56Development of innovative
treatment approaches to autism.
http://grants.nih.gov/grants/guide/rfa-files/RFA-MH-01-010.html
All material in this fact sheet is in the public
domain and may be reproduced or copied without
permission from the Institute. Citation of the
National Institute of Mental Health as the source is
appreciated.
Copyright © 2007 ASGC. All rights
reserved.
Autism Society of Greater Cleveland
P.O. Box 41066, Brecksville, Ohio 44141 (216)
556-4937
|
|