This is a time of high concern about violent behavior by young people. As a nation, we are in a period of reflection as to what can be done to stem this tide. The NIMH is currently involved in a "taking stock" activity to guide research into the areas where questions exist, with a special emphasis on identifying when and how to intervene. Youth violence is a complex problem and will require complex solutions. There is a natural desire to develop a "child violence" profile, but this not only risks a negative label on a child, but also risks missing the quiet, troubled child with a series of problems, who may actually become the most violent.
The NIMH has gathered information about risk factors,
experiences, and processes that are related to the development of aggressive,
antisocial, and violent behavior, including mental health problems, particularly
depression and externalizing behavior, associated with childhood and adolescence. NIMH research points
to the importance of a nurturing social environment in childhood, good
early education and success in academic areas. It has been learned that
the influence of peers, whether positive or negative, is of critical importance.
Research also suggests that current policies and approaches grouping or
housing troubled adolescents together may be the wrong approach, and it
is clear that there are no quick, inexpensive answers. Each research finding
suggests possible interventions that in turn need to be studied. Some proposed
interventions have been found to actually increase the negative behavior
and so due care must be taken. This overview highlights what is known about
risk factors for the development of antisocial and problem behavior, and the often
underutilized early prevention and intervention strategies.
Tragic events like the shootings at Santee High School capture
public attention and concern, but are not typical of youth violence. Most
adolescent homicides are committed in inner cities and outside of school.
They most frequently involve an interpersonal dispute and a single victim. On average, six or seven youths are murdered in this country
each day. Most of these are inner-city minority youths. Such acts of violence
are tragic and contribute to a climate of fear in schools and communities.
Research findings are identifying factors in the development
of aggressive and antisocial behavior from early childhood to adolescence
and into adulthood. Prospective longitudinal and intervention studies have
identified major correlates for the initiation, escalation, continuation,
and cessation of serious violent offending.
Many studies indicate that a single factor or a single defining situation
does not cause child and adolescent antisocial behavior. Rather, multiple
factors contribute to and shape antisocial behavior over the course of
development. Some factors relate to characteristics within the child, but
many others relate to factors within the social environment (e.g., family,
peers, school, neighborhood, and community contexts) that enable, shape,
and maintain aggression, antisocial behavior, and related behavior problems.
The research on risk for aggressive, antisocial and violent behavior
includes multiple aspects and stages of life, beginning with interactions
in the family. Such forces as weak bonding, ineffective parenting (poor
monitoring, ineffective, excessively harsh, or inconsistent discipline,
inadequate super-vision), exposure to violence in the home, and a climate
that supports aggression and violence puts children at risk for being violent
later in life. This is particularly so for youth with problem behavior,
such as early conduct and attention problems, depression, anxiety disorders,
lower cognitive and verbal abilities, etc. Outside of the home, one of
the major factors contributing to youth violence is the impact of peers.
In the early school years, a good deal of mild aggression and violence
is related to peer rejection and competition for status and attention.
More serious behavior problems and violence are associated with smaller
numbers of youths who are failing academically and who band together, often with other youth rejected by prosocial peers. Successful early adjustment at home
increases the likelihood that children will overcome such individual challenges
and not become violent. However, exposure to violent or aggressive behavior
within a family or peer group may influence a child in that direction.
Types and Severity of Antisocial Behavior
The types and severity of antisocial behaviors exhibited by youths vary
greatly and include lying, bullying, truancy, starting fights, vandalism,
theft, assault, rape, and homicide. As a rule, the older the age of onset,
the fewer the number of antisocial youths who will engage in seriously
aggressive and violent behavior. Longitudinal studies show that many children
who engage in antisocial behavior in childhood continue to do so at least
Longitudinal research has identified types of youth who progress to
adolescent antisocial behavior, multiple pathways through which it develops
and persists, and the multiple factors that shape this risk. This research
has identified two types of life course trajectories: life course persistent,
which is viewed as a form of psycho-
pathology, and adolescence limited, which is identified only
in select social situations. The distinction between these two types of
individuals is very useful, both as a way of thinking about developmental
knowledge and as a tool for targeting the right interventions for antisocial
Research in this area has generated evidence for this way of thinking
about how adolescents grow and has investigated the relationship between
adolescent problem behavior and cognitive deficits. Life course persistent
individuals begin antisocial behavior early in childhood and continue into
adulthood, after their adolescence limited counterparts stop.
Life course persistent behavior has been correlated with neurological
deficits and pathological behaviors, (e.g., impulsivity) which are exacerbated
when they are combined with stressful home situations. In one study of
13 year olds, individual differences - such as deficits in sensory, perceptual,
and cognitive abilities, including the use of languageC were shown to predict
participation in crime five years later. For instance, boys with poorer
verbal functioning initiated delinquent behavior at younger ages. It has
also been demonstrated that boys with poorer neuropsychological functioning,
especially verbal functioning at age 13, were more likely to have committed
crimes at age 18 than were their counterparts with better neuropsychological
functioning at age 13.
From about 4 years of age on, boys are more likely than girls to engage
in both aggressive and nonaggressive antisocial behavior. Much remains
to be learned about the causes of gender differences in antisocial behavior,
but based on what is known, it is suspected that antisocial behavior might
need to be defined somewhat differently for the two genders. In
contrast to overt aggression, which inflicts harm through physical damage
or the threat of such damage more common in boys, social aggression by
girls harms through damage to peer relationships; study of this form of
aggression may be crucial to understanding the aggressive development of
girls. The NIMH is currently funding research on the antecedents and consequences
of aggression for girls, as well as for boys, knowledge that can be used
to develop empirically-based interventions for aggressive children of both
Antisocial Behavior Co-Occurring with Child Psychopathology
There is strong evidence for the co-occurrence of two or more syndromes
or disorders among children with behavioral and emotional problems. Many
people think that children either act out or turn their feelings inward,
but the truth is more complex. The obviously angry adolescent has other
conditions such as anxiety disorders and depression (as seen in the quiet
withdrawn young person) more often than would occur by chance. Research
in this area indicates that very young children with conduct problems and
anxiety disorders or depression display more serious aggression than youths
with only conduct problems. It is not entirely clear whether depression precipitates
acting out, whether impairments and predispositions for acting out lead
to depression, or whether there are underlying causal factors that are
responsible for the joint display of such problems.
It is very common for youth with conduct problems to also display symptoms
of attention deficit hyperactivity disorder (ADHD), the most commonly diagnosed
behavioral disorder of childhood. The diagnosis is made by the presence
persistent age-inappropriate inattention and impulsivity, often coexisting
with hyperactivity. This co-occurrence is often associated with an early
onset of aggression and impairment in personal, interpersonal, and family
functioning. Furthermore, academic underachievement is common in youth
with early onset conduct problems, ADHD, and adolescents who display delinquent
Individual Liability and Genetic Factors
Identifying numerous genes that may play a role in any complex disorder
is a formidable task and is only the first step in understanding how a
gene or genes affect an individual. Genes act by producing specific proteins
that may contribute to a particular biological or behavioral trait. Every
human carries between 80,000 and 100,000 genes; the products of these genes
S acting together and in combination with the environment B help shape
every human characteristic. It has become clear that the genetics of vulnerability
to certain behaviors or mental disorders is complex. We still do not know
how many different genes might contribute to vulnerability for any personality
trait or specific mental disorder, nor do we know the nature of the nongenetic
effects (such as environmental factors) that convert vulnerability into
Our understanding of the nature of genetic influences on antisocial
behavior is similarly incomplete. However, research on differences in the
magnitude of genetic and environmental influences on different kinds of
conduct problems is providing a key to understanding the developmental
origins of antisocial behavior. Many twin and adoption studies indicate
that child and adolescent antisocial behavior is influenced by both genetic
environmental factors, suggesting that genetic factors directly influence
cognitive and temperamental predispositions to antisocial behavior. These
predisposing child factors and socializing environments, in turn, influence
Research suggests that for some youth with early onset behavior problems,
genetic factors strongly influence temperamental predisposition, particularly
oppositional temperament, which can affect experiences negatively. When
antisocial behavior emerges later in childhood or adolescence, it is suspected
that genetic factors contribute less, and such youths tend to engage in
delinquent behavior primarily because of peer influences and lapses in
parenting. The nature of the child's social environment regulates the degree
to which heritable early predisposition results in later antisocial behavior.
Highly adaptive parenting is likely to help children who may have a predisposition
to antisocial behavior. Success in school and good verbal ability tend
to protect against the development of antisocial behavior, pointing to
the importance of academic achievement.
Parent and Family Factors
Research has demonstrated that youths who engage in high levels of antisocial
behavior are much more likely than other youths to have a biological parent
who also engages in antisocial behavior. This association is believed to
reflect both the genetic transmission of predisposing temperament and the
maladaptive parenting of antisocial parents.
The importance of some aspects of parenting may vary at different ages.
For example, inadequate supervision apparently plays a stronger role in
late childhood and adolescence than in early childhood. There is evidence
from many studies that parental
use of physical punishment may play a direct role in the development
of antisocial behavior in their children. In longitudinal studies, higher
levels of parental supervision during childhood have been found to predict
less antisocial behavior during adolescence. Other researchers have observed
that parents often do not define antisocial behavior as something that
should be discouraged, including such acts as youths bullying or hitting
other children or engaging in "minor" delinquent acts such as shoplifting.
Research examining the mental health outcomes of child abuse and neglect
has demonstrated that childhood victimization places children at increased
risk for delinquency, adult criminality, and violent criminal behavior.
Findings from early research on trauma suggest that traumatic stress can
result in failure of systems essential to a person's management of stress
response, arousal, memory, and personal identity that can affect functioning
long after acute exposure to the trauma has ended. One might expect that
the consequences of trauma can be even more profound and long lasting
when they influence the physiology, behavior, and mental life of a developing
child or adolescent.
Antisocial children with earlier ages of onset tend to make friends with
children similar to themselves. Consequently, they reinforce one another's
antisocial behavior. Children with ADHD are often rejected due to their
age-inappropriate behavior, and thus are more likely to associate with
other rejected and/or delinquent peers. The influence of delinquent peers
on lateronset antisocial behavior appears to be quite strong. Association
with antisocial peers has been shown to be related to the later emergence
of new antisocial behavior during adolescence among youths who had not
exhibited behavior problems as children.
Less adult supervision allows youths to spend more time with delinquent
peers. Thus, improving parental supervision may be an important way to
reduce the effects of delinquent peer influence. Ongoing research is examining
how neighborhood effects on antisocial behavior are mediated by the willingness
of neighbors to supervise youths and possibly reduce the likelihood of
association with delinquent peers in the neighborhood.
An inverse relationship of family income and parental education with antisocial
behavior has been found in many population-based studies. Across gender
and ethnicity, much of the inverse relationship between family income and
antisocial behavior is accounted for by less parental monitoring at lower
levels of socioeconomic status.
Prevention and Intervention
In recent years, several effective programs and strategies to prevent
youth violence have been developed and tested.
The Nurse Home Visitation Program, partly funded by the NIMH, is a 20-year
model of research in which nurses visit mothers beginning during pregnancy
and continuing through their child's second birthday to improve pregnancy
outcomes, promote children's health and development, and to strengthen
families' economic self-sufficiency. This program, currently underway in
New York, Colorado, and Tennessee, appears to benefit high-risk families,
particularly low-income unmarried women, reducing rates of childhood injury,
child abuse and neglect, and other risk factors for early-onset antisocial
behavior in children. Long-term follow-up of the children in two of the
studied locations indicated that by age 15, they had fewer behavioral problems
related to the use of drugs and alcohol, fewer instances of running away,
fewer arrests and convictions, and fewer sexual partners, as compared to
counterparts randomly assigned to receive comparison services.
Hawaii's Healthy Start Program is designed to prevent child abuse and
neglect and promote child health and development in newborns of families
classified as highly stressed and/or at risk for child abuse and neglect.
Following a successful pilot study, this program is now operating statewide,
and has inspired adaptations in other locations. The program uses a home
visitation model to help family members cope with the challenges of child
rearing, to teach effective parenting and problem-solving skills, and to
link families to necessary services such as childcare, income and nutritional
assistance, and pediatric primary care. After two years of service, mothers
reported improved parenting efficacy, decreased parenting stress, more
use of non-violent discipline, better linkage with pediatric care, as well
as decreased injury due to partner violence in the home, as compared with
a control group.
The Administration on Children, Youth and Families (ACYF) and the NIMH
have awarded several research grants as the core component of a new young
children's mental health research initiative designed to develop and test
applications of theory-based research or state-of-the-art techniques for
the prevention, identification and/or treatment of children's mental health
disorders within a Head Start context. Among these are projects to develop
screening tools for identifying behavior problems in preschool children,
to test the effectiveness of research-based classroom interventions for
very young children with serious disruptive behavior problems, and to assess
the mental health needs of this vulnerable population.
Recent studies have indicated that between 70 and 80 percent of children
with diagnosable mental disorders who receive services are served within
the school system, primarily by school psychologists and guidance counselors.
The NIMH has supported many projects that seek to develop, establish, and
improve school-based mental health service delivery systems. These projects
range from broad programs intended to enhance the social and problem solving
skills of all students, to highly specific programs designed to treat children
already showing symptoms of mental health problems. Programs also range
from those that intervene at multiple levels, including the child, parents,
peers, and teachers, to those that focus solely on the child. For example,
research is aimed at developing techniques for teachers to manage disruptive
students. Several strong, multi-faceted programs that aim to prevent severe
and persistent conduct problems in children have been launched.
The Families and Schools Together (FAST) Track Program is a multi-faceted,
multi-year program designed for aggressive children in kindergarten starting
at age 6. A four-site study in North Carolina, Pennsylvania, Tennessee,
and Washington, the program involves working with the child, the family
in their home, and school system, including teachers. Preschool children
at high risk were identified at 55 different schools. These children were
randomly assigned for intervention or no intervention.
The children initially enrolled in the study are now young adolescents.
An evaluation of FAST TRACK indicated that by the third grade, students
who took part in the program showed less oppositional and aggressive behavior
and were less likely to require special education services than students
who did not take part.
The Linking the Interests of Families and Teachers (LIFT) Program (in
Oregon) is a 10-week intervention created for children and families who
are at risk for the development of conduct problems due to residence in
neighborhoods characterized by high rates of juvenile delinquency. The
LIFT Program is a multi-component intervention that includes parent training,
social skills training, a playground behavioral program, and regular communication
between teachers and parents. Following program participation, students
engaged in significantly less aggressive behaviors on the playground, parents
demonstrated fewer negative behaviors during family problem-solving activities,
and teachers reported improved student social behavior and peer interactions.
Three years following the intervention, students who received the program
were less likely to engage in consistent alcohol use, less likely to have
troublesome friends, and less likely to have been arrested for the first
time than students who did not receive the program. Students were also
less likely to demonstrate inattentive, impulsive, overactive, and disruptive
behaviors in the classroom than students who did not receive the program.
Programs have also been initiated which seek to enhance the skills and
knowledge of all children in order to decrease their risk of future emotional
and behavioral problems. NIMH has sponsored the Promoting Alternative Thinking
Strategies (PATHS) Curriculum, based in Washington state, which teaches
children about self-control, understanding emotions, and problem solving.
The PATHS curriculum has been evaluated using students in both regular
education and special education classrooms. Students who received the PATHS
curriculum demonstrated better knowledge of emotions than children who
did not receive the curriculum. This emotional knowledge is thought to
underlie the development of necessary social skills such as friendship
development and maintenance, anger management, conflict resolution, and
appropriate problem solving.
Development of Depression
NIMH research is investigating promising and successful interventions to
prevent and treat adolescent depression, which often coexists with conduct
problemsSa combustible mix that can result in violence, both against self
and others. Several NIMH projects focus on determining whether cognitive
therapy techniques that have been found to be effective for treating depression
in adults can be applied to prevent depression in adolescents. Such research
tests, among other things, the effects of after-school programs, which
are based on cognitive therapy and social problem-solving techniques and
delivered by school staff. Findings from this type of research are mixed,
with more intensive interventions appearing to have at least initial effects
of reducing or preventing depressive symptoms. Additional work is needed
to determine the optimal length and intensity of interventions as well
as approaches for sustaining their effects.
For example, the Coping with Stress Course was designed to prevent the
onset of depressive disorders among adolescents who report high levels
of depressive symptoms. With programs in Oregon, Maryland, and Ohio, this
group course teaches adolescents cognitive skills to identify and challenge
negative or irrational thoughts and beliefs that may contribute to the
development of depression. Evaluation showed that the course was successful
in reducing the number of cases of depressive disorder among adolescents
at risk. In fact, twice as many students in the no-treatment group developed
a depressive disorder than in the treatment group. Students in the treatment
group also reported fewer depressive symptoms and better adjustment than
students in the untreated group. However, with the passage of time, differences
between the treatment and no-treatment groups decreased.
Other projects are testing the effects of pharmacological and psychosocial
treatments for youth with depression (aged 12-17 years). Going beyond the
effects of treatment on symptoms of depression, this research also focuses
on the impact of the interventions on functioning in school, at home, and
in the community.
Effective Interventions for Delinquent Youth
It is important in evaluating interventions for delinquents to document
what has not worked, as well as what has. For example, group-home approaches
that pool delinquent youth together will, in some cases, exacerbate and
escalate youth violence. Even promising interventions for delinquent youth
can be overwhelmed by the negative effect of grouping such youth together.
This research finding has led to two highly successful treatment models
for serious offending delinquents. One is multisystemic therapy (MST),
in which specially trained therapists work with the youth and family in
their home, with a particular focus on changing the peers with whom the
youths associate. MST therapists identify strengths in the families and
use these strengths to develop natural support systems and to improve parenting.
Specific interventions are individualized to the family and address the
needs of the child, family, school, peers, and neighborhood. Multiple,
rigorous outcome evaluations have demonstrated the efficacy of this approach,
and an independent cost-benefit analysis found that this model had a very
high cost-benefit payoff. Although a number of states are now attempting
to implement this model, the majority of programming for delinquent youth
is based on models that bring together youth with problem behavior, rather
than target separation of youth from problem peers.
The other model is Therapeutic Foster Care. This model offers a community-based
intervention for serious and chronic offending delinquents. Therapeutic
foster parents are carefully selected and supported with research-based
procedures for working with serious and chronic delinquents in their homes.
Treatment typically lasts 6 to 7 months. This intervention results in fewer
runaways and fewer program failures than the usual placement in group homes
is less expensive, and is dramatically more effective in reducing delinquency
than traditional group homes. The Foster Family-based Treatment Association,
developed under NIMH leadership, now has some 400 members across the U.S.
who promote the use of this research-based and effective model.
As important as the problem of violence is, there will be no quick,
inexpensive, and fail-safe solution. Recent years have witnessed a strong
growth in our understanding of the risk factors and processes that contribute
to and shape child and adolescent antisocial behavior. Yet gaps remain
in our scientific understanding of how child, family, school/community,
and peer factors interact, and which are the most appropriate targets for
prevention and early intervention in different settings. We are also learning
that being "at risk" does not doom any one child to become violent; conversely,
the apparent absence of certain risk does not necessarily protect any one
child from problem behavior. The development of serious behavior
problems is best understood as a dynamic interaction between child predispositions
and various influences on children's lives (family, peer, and school/community)
that change over critical periods of development.
Successful programs that produce long-term sustained effects may need
to involve long-term intense interventions to target the multiple factors
that can lead to negative outcomes such as family conflict, depression,
social isolation, school failure, substance abuse, delinquency, and violence.
The fundamental premise of some of these interventionsCwhich separate youth
with problem behaviorsCchallenges the policies, programs and procedures
that currently bring problem youth together. Continued research is needed
to determine the most appropriate targets for prevention and early intervention
that will produce lasting change. Answers are emerging about which programs
are most successful, but assessments need to be made about their costs,
as well as if they will work for all groups of children and adolescents.
The NIMH is committed to encouraging and supporting this research, and
has a long and enduring history of support for research and research training
on violence. Throughout the 1950s, and early '60s, NIMH provided research
and research training support that built much of the modern field of behavioral
science, and much subsequent research on violence has built upon that foundation.
In 1966, NIMH created a Center for Studies of Crime and Delinquency, which
was the locus of pioneering research on aggressive, antisocial, and violent
behavior and its consequences. NIMH-supported research has generated information
needed to identify, treat, and prevent not only the causes of violent
behavior but also the effects of violence on victims, for example,
child abuse. Most recently, the NIMH has assumed a lead role, along with the Substance Abuse and Mental Health Services Administration and the Centers for Disease Control and Prevention, in developing a Surgeon General's report on the topic of youth violence. The NIMH believes that this report, as follow-up to the Surgeon General's Report on Mental Health, will be an effective and highly credible means of educating the public about the interaction of mental disorders and youth violence.
The Broad NIMH Research Program
In addition to research on violence, NIMH supports and conducts a broad
based, multi-disciplinary program of scientific inquiry aimed at improving
the diagnosis, prevention, and treatment of mental disorders. These
illnesses include schizophrenia, manic-depressive illness, clinical depression,
panic disorder, and obsessive-compulsive disorder.
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 the world's largest registry of families affected
by schizophrenia, manic-depressive illness, and Alzheimer's disease. Scientists
are able to examine the genetic material of these family members with the
aim of pinpointing genes involved in the diseases.
Human Brain Project
This multi-agency 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
for simultaneous study by interested researchers.
Prevention Research Initiative
Prevention efforts seek to understand the development and expression of
mental illness throughout life so that appropriate interventions can be
found and applied at multiple points during the course of illness. Recent
advances in biomedical, behavioral, and cognitive sciences have led NIMH
to formulate a new plan that marries these sciences to prevention efforts.
While the definition of prevention will broaden, the aims of research will
become more precise and targeted.
More Than 2,000 Grants and Contracts
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 involving 9,000 patient
visits per year at its own facilities on the National Institutes of Health
campus in Bethesda, MD, and elsewhere. NIMH research projects focus on:
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
neuro-biology, 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 HIV (human immunodeficiency
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-morbidity 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
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
psychotherapies and pharmacotherapies for specific disorders