Nature and nurture should not be seen as enemies or complete opposites. Instead, they should be seen as two realities that work together to make up the human experience. Nature was made to be cared for.
Recent and important studies have shown that what happens to a child in their early years can change both the physical and chemical makeup of their brain. In particular, being abused or ignored as a child can change a person's body in a way that can't be fixed. These changes in the body may make it more likely that the person will have depression or anxiety in the future.
A major study of depressed women in the US with no history of abuse found that women who were abused as children have hormonal responses to stress that are much higher than women with no history of abuse. It suggests that being abused as a child is linked to a stress response hormone system that stays overactive, which may make a person more likely to have psychiatric disorders as an adult.
The study, which was done at Emory University and led by Dr. Charles Nemeroff, looked at women with clinical depression who had been abused as children, women with clinical depression who had never been abused, and healthy women. Each person was put through a mildly stressful situation and asked to solve simple math problems out loud for a group of serious, emotionless judges.
Cortisol and ACTH, two hormones that play a key role in how a person responds to stress, were measured in each subject as she did the task. It was found that the levels of these hormones were especially high in depressed women who had been abused as children. In fact, their ACTH response indicators were more than six times higher than those of healthy women.
In other studies by the same group, it was found that women who had been abused as children had abnormal development of the hippocampus. This suggests that abuse as a child has other physical effects that could lead to permanent changes in the brain later in life.
Abuse or neglect in childhood can also hurt other parts of the brain. Even though the basic unit of the brain is already there when a person is born, the neuronal pathways that tell the body how to react to different things are still being made.
Most of these connections are made in the first three years of a child's life, which is a very important time. If a child is exposed to mostly bad things early in life, it can make it harder for them to form lasting relationships and respond well to good things. Even though this may be done to help the child stay alive, it can cause the person long-term problems.
Other research shows that the brains of children who are severely neglected tend to be smaller than average and have parts of the cortex that aren't as developed. The long-term effects of this are still being looked into, but it shows yet another way that a person's environment, or lack of it, can change their genes.
Nature and nurture are two important parts of a person's health. Knowing this will undoubtedly be a very useful tool in the study and treatment of psychiatric illness, and it may lead to even better treatments in the future.
