Perry

                The Impact of Abuse and Neglect on the Developing Brain
                              Bruce D. Perry, M.D., Ph.D. John Marcellus, M.D.
                                         The Child Trauma Academy
                                            www.ChildTrauma.org

Each year in the United States alone, there are over three million children that are abused or
neglected. These destructive experiences impact the developing child – increasing risk for
emotional, behavioral, academic, social and physical problems throughout life. The purpose of this
article is to outline how these experiences may result in increased risk – by influencing the
development and functioning of the child’s brain.

The Brain
The human brain is an amazing and complex organ. It allows us to think, act, feel, laugh, speak,
create and love. The brain mediates all of the qualities of humanity, good and bad. Yet the core
‘mission’ of the brain is to sense, perceive, process, store, and act on information from the
external and internal environment to promote survival. In order to do this, the human brain has
evolved an efficient and logical organization structure. The brain has a bottom-up organization.
The bottom regions (i.e., brainstem and midbrain) control the most simple functions such as
respiration, heart rate and blood pressure regulation while the top areas (i.e., limbic and cortex)
control more complex functions such as thinking and regulating emotions.

Brain Development
At birth, the human brain is undeveloped. Not all of the brain’s areas are organized and fully
functional. It is during childhood that the brain matures and the whole set of brain-related
capabilities develop in a sequential fashion. We crawl before we walk, we babble before we talk.
The development of the brain during infancy and childhood follows the bottom-up structure. The
most regulatory, bottom regions of the brain develop first; followed, in sequence, by adjacent but
higher, more complex regions. The process of sequential development of the brain and, of
course, the sequential development of function, is guided by experience. The brain develops and
modifies itself in response to experience. Neurons and neuronal connections (synapses) change in
an activity-dependent fashion. This ‘use-dependent’ development is the key to understanding the
impact of neglect and trauma on children. These areas organize during development and
change in the mature brain in a "use-dependent" fashion. The more a certain neural system is
activated, the more it will "build-in" this neural state -- what occurs in this process is the creation
of an "internal representation" of the experience corresponding to the neural activation. This "use-
dependent" capacity to make an "internal representation" of the external or internal world is the
basis for learning and memory. The simple and unavoidable result of this sequential
neurodevelopment is that the organizing, "sensitive" brain of an infant or young child is more
malleable to experience than a mature brain. While experience may alter and change the
functioning of an adult, experience literally provides the organizing framework for an infant and
child. The brain is most plastic (receptive to environmental input) in early childhood. The
consequence of sequential development is that as different regions are organizing, they require
specific kinds of experience targeting the region’s specific function (e.g., visual input while the
visual system is organizing) in order to develop normally. These times during development are
called critical or sensitive periods.

Traumatic Experiences and Development
With optimal experiences, the brain develops healthy, flexible and diverse capabilities. When there
is disruption of the timing, intensity, quality or quantity of normal developmental experiences,
however, there may be devastating impact on neurodevelopment – and, thereby, function. For
millions of abused and neglected children, the nature of their experiences adversely influences the
development of their brains. During the traumatic experience, these children’s brains are in a state
of fear-related activation. This activation of key neural systems in the brain leads to adaptive
changes in emotional, behavioral and cognitive functioning to promote survival. Yet, persisting or
chronic activation of this adaptive fear response can result in the maladaptive persistence of a fear
state. This activation causes hypervigilance, increased muscle tone, a focus on threat-related cues
(typically non-verbal), anxiety, behavioral impulsivity – all of which are adaptive during a
threatening event yet become maladaptive when the immediate threat has passed. This is the
dilemma that traumatic abuse brings to the child’s developing brain. The very process of using the
proper adaptive neural response during a threat will also be the process that underlies the neural
pathology, which causes so much distress and pain through the child’s life. The chronically
traumatized child will develop a host of physical signs (e.g., altered cardiovascular regulation) and
symptoms (e.g., attentional, sleep and mood problems) which make their lives difficult.
There is hope, however. The brain is very plastic – meaning it is capable of changing in response
to experiences, especially repetitive and patterned experiences. Furthermore, the brain is most
plastic during early childhood. Aggressive early identification and intervention with abused and
neglected children has the capacity to modify and influence development in many positive ways.
The elements of successful intervention must be guided by the core principles of brain
development. The brain changes in a use-dependent fashion. Therapeutic interventions that
restore a sense of safety and control are very important for the acutely traumatized child. In cases
of chronic abuse and neglect, however, the very act of intervening can contribute to the child’s
catalogue of fearful situation. Investigation, court, removal, placement, re-location, and re-
unification all contribute to the unknown, uncontrollable and, often, frightening experiences of
the abused child. Our systems, placements and therapeutic activities can diminish the fearful
nature of these children’s lives by providing consistency, repetition (familiarity), nurturance,
predictability and control (returned to the child). Yet the poorly coordinated, over-burdened and
reactive systems mandated to help these children rarely can provide those key elements.

Prevention and Policy
What we are as adults is the product of the world we experienced as children. The way a society
functions is a reflection of the childrearing practices of that society. Today, we reap what we
have sown. Despite the well-documented critical nature of early life experiences, we dedicate few
resources to this time of life. We do not educate our children about development, parenting or
about the impact of neglect and trauma on children. As a society we put more value on requiring
hours of formal training to drive a car than we do on any formal training in childrearing. In order
to prevent the development of impaired children, we need to dedicate resources of time, energy
and money to the complex problems related to child maltreatment. We need to understand the
indelible relationship between early life experiences and cognitive, social, emotional, and physical
health. Providing enriching cognitive, emotional, social and physical experiences in childhood could
transform our culture. But before our society can choose to provide these experiences, it must
be educated about what we now know regarding child development. Education of the public
must be coupled with the continuing generation of data regarding the impact of both positive
and negative experiences on the development of children. All of this must be paired with the
implementation and testing of programs dedicated to enrich the lives of children and families and
programs to provide early identification of, and proactive intervention for, at-risk children and
families. The problems related to maltreatment of children are complex and they have complex
impact on our society. Yet there are solutions to these problems. The choice to find solutions is
up to us. If we choose, we have some control of our future.

If we, as a society, continue to ignore the laws of biology, and the inevitable neurodevelopmental
consequences of our current childrearing practices and policies, our potential as a humane society
will remain unrealized. The future will hold sociocultural devolution -- the inevitable consequence
of the competition for limited resources and the implementation of reactive, one-dimensional and
short-term solutions.

Acknowledgments
This is an Academy version of an article originally appearing in Colleagues for Children.
Official citation: Perry, B.D. and Marcellus, J.E. (1997) The Impact of Abuse and Neglect on the
Developing Brain. Colleagues for Children. 7: 1-4, Missouri Chapter of the National Committee to
Prevent Child Abuse