Is there a link between childhood abuse and depression?
Being a victim of child abuse places one at significant risk for adult depression. Studies have found that a majority of young adults who experienced abuse in childhood have had at least one psychiatric disorder diagnosed at the age of 21 years. The biopsychosocial model can be used to illustrate the elevated risk. Biologically, many victims of child abuse have family histories of mental illness and depression, which alone can predispose someone for adult depression. Also, childhood abuse can result in physical injury to the brain. In addition to poor physical health, studies have shown evidence for impaired brain development secondary to abuse and neglect. Such brain damage can result from direct effects (e.g., shaken baby syndrome) or from the effects of stress on the brain secondary to the hyperarousal that children experience when chronically abused.
Consequences of Child Abuse and Depression
Psychologically, the consequences of abuse can include low self-esteem, depression, and relationship difficulties. Suffering from child abuse may result in the development of a “learned helplessness” style of coping. Learned helplessness is a concept that developed out of the principles of classical (or Pavlovian) conditioning. Classical conditioning is a form of learning that occurs when a stimulus is paired in time with a reward that causes a response in the subject. Pavlov, a Russian physiologist, who used dogs as his subjects, conducted the basic experiments. In the experiment, a bell (stimulus) is paired with food (reward), causing the dog to salivate. After repeated pairings, the food could be removed, and the bell alone would cause the dog to salivate. In a similar experiment, a bell is paired with an electrical shock, causing the dog to jump to a safe area. After repeated pairings, the bell alone would signal the dog to jump to the safe area, thus avoiding the shock. However, suppose there is no safe area to jump to? After a while, the dog stops jumping, as there is no way to avoid the shock. This behavior is often accompanied by physiologic changes that mimic depression with the dog losing energy, appetite, and sleep. Even after a safe area is returned, the dog does not respond and take advantage of it because it has learned to believe that there is nothing that it can do to avoid the shock. Several human experiments have firmly established this as a phenomenon in humans as well. Feelings of helplessness are quickly established, and the generalization of these feelings to other situations can take over, making one also feel a sense of hopelessness, a feeling of wanting to give up, and a general loss of interest. The paradigm of learned helplessness fits perfectly with victims of child abuse. They are small and vulnerable. They are in the seemingly most protected environment of their lives, and it is filled with unpredictable threats with no possibility of escape. Additionally, they feel guilty that they are the cause of the abuse, further damaging their self-esteem and sense of hopefulness.
From a social standpoint, the likelihood of being a victim of child abuse increases dramatically in children born of young unwed mothers with little economic means and in those who suffer from depression. Most unwed mothers struggle with supporting their families and find themselves economically challenged between having to go on welfare to spend time raising their children or working at minimum wage jobs and risking neglecting their children. Under these circumstances, many women attach themselves to men whose investment in their children is significantly reduced because of their lack of genetic relatedness. The costs of raising children are far less likely to be tolerated by parents who are not invested in their children. Numerous studies of child abuse cross-culturally have demonstrated that the rates of child abuse dramatically increase with the presence of a stepparent.
Not all abused children will experience long-term consequences, however. Factors that affect long-term consequences include the child’s age and stage of development when the abuse occurred; the type of abuse; the frequency, duration, and severity of abuse; and the relationship between abuser and victim. There may be protective factors that improve long-term outcomes in abused children as well. These include resilience factors such as high intelligence and optimism in the child, access to social supports, and access to healthcare.