Biological and psychological effects of child abuse on the brain, explained

This article is the second in a series that will analyze the physical, biological effects of trauma on a child’s brain, investigate its in-depth psychological consequences and propose parenting techniques that may help lead us to a harmonious, nonviolent society.

The human brain can be divided into many sections. The amygdala is responsible for processing and memory of emotional reactions, in addition to the “fight or flight” instinct. The hippocampus controls spatial navigation and long-term memory. Corpus callosum facilitates communication between the two hemispheres. The prefrontal cortex, also known as the moral center, is the center for planning complex cognitive behaviors, personality expression, moderating social behavior, delaying gratification and decision-making.

Over the past few decades, there has been significant research about the psychology and neurobiology of violence. During the first four years of life, 90 percent of the brain develops through the experience of that child. The mind and its functions are created in the first few years of life through the child’s experiences with the world – especially with its mother.

“Neglect is awful for the brain. Without a reliable source of attention, affection, and stimulation, the wiring of the brain goes awry,” said Charles Nelson, professor of pediatrics at Harvard Medical School and Boston Children’s Hospital, of the horrors of childhood neglect and abuse.

The result is almost unquestionable long-term mental and emotional scarring.

Romanian children living in orphanages during the 1980s provide insight into the catastrophic effects of mistreatment. Nelson, along with other researchers, began studying such children after its brutal government was overthrown in 1989. At that time, there were more than 100,000 children in orphanages.

“They’d reach their arms out as though they’re saying to you, ‘Please pick me up.’ So you’d pick them up and they’d hug you. But then they’d push you away and want to get down. Then the minute they got down, they’d want to be picked up again. It’s a very disorganized way of interacting with somebody,” Nelson recalled.

The scientists realized that this was not caused by malnutrition but by a different kind of deprivation: that of nurture. Nim Tottenham, associate professor of psychology at the University of California in Los Angeles, conducted a study on orphans and brain activity. When typical children are shown images of their mothers, the response in the amygdala – the emotion center – is much greater than when they see a stranger. When the orphans were shown images of their adopted mothers, the amygdala signal did not discriminate a child’s mother from strangers.

Negligence outside of the womb can be just as catastrophic as inside. The brain of a baby is dependent on the mother’s brain to produce the correct neurotransmitters and hormones. When the appropriate nutrients are not delivered, the baby’s brain physically suffers. Global experiments show how depressed or angry mothers produce insecurely attached infants who often grow up to be violent adults. Hundreds of these worldwide studies show the effects of childhood trauma.

Cortisol – a hormone secreted by the adrenal glands – is a chemical that helps the body cope with stress. Studies have shown that when mothers are depressed or angry, both the mother’s and the child’s cortisol levels are elevated. Especially in cases of abuse, infants and children have abnormal secretions of cortisol, which impairs the natural way the body handles stress.

Neurobiologists have provided massive evidence that the neural fear system of an infant is located in the prefrontal cortex, the moral center, and the amygdala, the fight or flight system.

Specifically, the role of the amygdala is to remember a threat and generalize so it can be recalled in the future. Observations of the amygdalae of insecurely attached children show hyperactivity and increased size relative to kids without insecure attachment. These altered amygdalae cause increased adrenaline, cortisol and unnatural fight or flight mechanisms.

Additionally, those with insecure attachment have a much smaller prefrontal cortex, meaning less control over fear, anger and emotions like empathy, shame, compassion or guilt. This physical problem in the brain explains irrationality and violence, lashing out and disruptive behavior. The fight or flight mechanism is strong, while the restraint mechanism is weak.

When children experience maternal abandonment, abuse, neglect or dysfunction they release cortisol – which impairs the prefrontal cortex while stimulating their amygdala. In these traumatic scenarios, the amygdala imprints or burns the threatening mother in the child’s mind.

Brain scans reveal that “an enduring pattern, associated with destructive, defensive rage, is imprinted into an immature, inefficient orbitofrontal [cortical] system [and amygdala] during trauma in early childhood.”

Stress and abuse-related hyperarousal in the amygdala and other parts of the brain are always stimulated, and, thus, the child may frequently experience ADHD, anxiety, impulsivity and sleep problems.

There exists a strong graded relationship between exposure to abuse or household dysfunction during childhood and the leading causes of death in adults. Increased exposure to adverse childhood experiences (ACEs) showed a relationship to the presence of adult diseases including ischemic heart disease, liver disease, chronic lung disease, skeletal fractures and multiple forms of cancer.

The CDC-Kaiser Permanente Adverse Childhood Experiences Study found that even after accounting for age, race, sex, childhood stressors, adult health behaviors and adult household income, individuals who had been physically abused as children were 47 percent more likely to develop cancer than those who had not been assaulted. One possible explanation is that because children under chronic stress produce unnatural levels of cortisol, the hormone imbalance interferes with the immune system’s ability to detect and eliminate cancer cells.

One further crucial area of the brain, the insula, becomes damaged during early stress. The insula is a deep area of the cortex that contains most of the “mirror neurons” that make people capable of empathy.

Psychologist Dr. Bruce Perry published many studies that show abnormal brain development following neglect and abuse in early childhood. He found such abuse leads to significantly smaller brains, decreased activity in the prefrontal cortex – including the insula, hippocampal damage and amygdaloid over-excitement that produces “electrical storms” similar to those experienced by patients with temporal lobe epilepsy – seizures that induce violence and hallucinations.

Studies show that abused and neglected children have poorly integrated cerebral hemispheres. This poor integration and underdevelopment of the prefrontal cortex is the cause of symptoms such as difficulty regulating emotion, lack of cause-and-effect thinking, inability of the child to articulate emotion, an inherent sense of memory, inability to accurately recognize emotion in others and a lack of conscience.

“People with childhood histories of trauma, abuse, and neglect make up almost the entire criminal justice population in the United States,” concluded Bessel van der Kolk, a well-known expert on dissociated states of mind.

James Gilligan, a prison psychiatrist revealed abuse as a commonality between violent criminals.

“As children, these men were shot, axed, scalded, beaten, strangled, tortured, drugged, starved, suffocated, set on fire, thrown out of windows, raped, or prostituted by mothers who were their “pimps”… Some people think armed robbers commit their crimes in order to get money. But when you sit down and talk with people who repeatedly commit such crimes, what you hear is, ‘I never got so much respect before in my life as I did when I first pointed a gun at somebody,” commented Gilligan.

It is important to not only note the association between ACEs and child abuse but also the biological reasons why. Knowing the relationship and its cause leads to an understanding of how to avoid dysfunctional behavior later in life. My next article will criticize parenting techniques and propose methods that promote peace and nonviolence.

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