WARNING
The following describes accounts of child sexual and physical abuse, which the Innocent Lives Foundation works to prevent. This blog contains content that some individuals may find disturbing or distressing in nature. Please be emotionally prepared before proceeding.
Names, locations, and other identifying information have been changed for the safety of the victims and the Innocent Lives Foundation team. Any similarity to actual names, living or dead, is purely coincidental.
It has been well established, throughout both the empirical literature and clinical practice, that the experience of childhood adversity, including neglect, trauma, and abuse, is associated with an increased risk of later psychopathology. It is possibly less widely recognized, however, that childhood adversity also increases the risk of later physical illness and immune dysregulation. Advancements in research over the last decade have demonstrated that the developmental stress caused by such experiences may underpin these later-life consequences.
In this blog, we are going to look to understand the impact of how stress resulting from childhood maltreatment causes normal neurological and psychological development processes to be altered. However, it is important to first have a clear understanding of what the stress response is and why it is an adaptive and lifesaving process.
What is the stress response?
After the experience of a threatening event, the body will initiate the stress response, or in other words, it will activate the HPA axis. The HPA axis begins with the hypothalamus, which after perceiving a stressor, begins the process of releasing a series of hormones as a way of transmitting warning signals throughout the body.
To get technical, the hypothalamus releases Corticotrophin Releasing Factor (CRF) into the bloodstream, which takes a ride to the pituitary gland, leading to the production of Adrenocorticotrophic hormone (ACTH). ACTH in turn also hitches a ride and travels through the bloodstream to the adrenal glands, leading to the production of corticosteroids, the most important here being cortisol. This is where you really need to pay attention, the release of cortisol causes stored glucose to be utilized as a supply of energy to better deal with the stressor. Alongside this, we see nonessential processes, like digestion, get slowed or shut down whilst heart rate and increased blood pressure increase, as well as increased blood flow to the skeletal muscles. The release of corticosteroids also causes inflammation and interferes with cognitive functions, such as impaired memory and information processing.
In the face of a potential threat, this process is lifesaving. However, when stress becomes chronic this system is inappropriately activated and becomes maladaptive.
The effects of childhood trauma
The chronic or severe stress suffered by children exposed to trauma has serious consequences, with the excessive release of corticosteroids causing dysregulation of the HPA axis. The over-release of corticosteroids can suppress the effectiveness of the immune system, reducing the body’s ability to fight off antigens and maintain good health. When the immune system is suppressed as such, we are susceptible to infections and illnesses that we would have otherwise been able to fight off. Not only this, but the increase in heart rate can strain the circulatory system, increasing one’s risk of cardiovascular problems such as coronary heart disease. Given that part of the stress response involves suppressing digestion during stress and increasing digestion once it has surpassed, it is no coincidence that psychological struggles are often experienced alongside digestive disturbances. The continued inhibition and overactivity of the digestive system observed in early life subsequently reduces the health of the digestive system and may lead to later diseases and even cancers of the bowels.
It should be noted that trauma experienced at any age can lead to HPA dysregulation, but it is particularly dangerous when such experiences occur in early life when the brain is in critical stages of development. As our early years can lay the foundations for coping with adversity in later life, dysregulation at this stage lays the groundwork for continued dysregulation and problem-coping later in life. Indeed research has shown that not only do children show dysregulation of the HPA axis during the time period in which they experienced maltreatment, but this dysregulation persists into their later life. For example, research on adults who experienced childhood adversity has demonstrated that when faced with a stressor, cortisol responses are abnormal compared to healthy controls. What’s more, the direction of cortisol response observed among maltreated individuals is not always consistent, with different subtypes of abuse and neglect leading to either an over-release or an under-release of cortisol, although neither is good news. This dysregulation of HPA axis responsivity, both heightened and dampened, is associated with adult psychopathology, such as the increased risk of anxiety, depression, self-harm, and risk of suicide. The chronic over-secretion of CRF can also lead to structural changes in the brain, such as decreased hippocampal volume, subsequently impairing information processing ability and memory. The decreased hippocampal volume, in turn, has been observed in individuals with major depressive disorder and PTSD. Alongside this, the hormonal abnormalities observed during chronic stress stressors may elevate emotional reaction, suppress emotional control, and increase risk of depression.
Although we have only just scratched the surface in this blog, one thing that should be readily apparent is that the effects of childhood adversity do not dissipate once the maltreatment has stopped, they stay with victims and affect their daily lives as adults. In other words, the underlying psychobiological mechanisms that are crucial for survival become dysregulated leading to increased disease risk and risk of poor mental health over time.