Studies on neuroplasticity have become increasingly popular in the last several years. It was once thought that our brain was fixed and unchanging once we enter adulthood. Research throughout the last few decades has determined that in fact, our brain has the ability to change and create new neural pathways as well as produce new neurons, a process labeled as neurogenesis (Doidge, 2015). This finding is significant because if the brain has this ability to change, we have the ability to change our way of thinking and possibly improve mood.
Neural pathways in the brain are strengthened with repetition. One way to describe this process is “the neurons that fire together, wire together.” Constant repetition of an experience leads to changes within the brain’s structure and how the neurons process that experience. The more consistent this experience is, the stronger these neurons bond.
From a relational perspective, if a child is treated with consistent love, nurturing, and caring by his or her parents, the brain’s default is to find positive healthy relationships that repeat this pattern of receiving love and nurturance. If a child is treated with ongoing neglect or abuse, the brain’s default response would be to find relationships that fit this similar pattern of neglect or abuse. Because these neural pathways have been solidified through years of abuse, it can be difficult to change. These children grow into adults who enter unhealthy relationships, potentially resulting in symptoms of depression or anxiety in addition to the post-traumatic stress disorder (PTSD) they may have developed from their childhood trauma.
Our brain consists mainly of three parts: the reptilian brain, the limbic system, and the neocortex. Our reptilian brain is the most primitive part of the brain, located in the brain stem right above where the spinal cord meets the skull. This part of our brain is responsible for the most basic needs of survival: our ability to breathe, sleep, wake up, urinate, defecate, regulate body temperature and the like. Above our reptilian brain is the limbic system. This is the area of the brain which holds our emotions, also warning us of potential danger. The final and top layer of the brain, the neocortex, is the rational part of our brain. This is responsible for understanding abstract thought, the use of language to express emotions rather than acting on impulses, and the ability to plan for our future.
Whenever we experience an event, the information goes to our thalamus, located in the limbic system in the middle part of our brain. The thalamus filters the information, then sends it to the amygdala, also located in the limbic system. The amygdala determines if the information is a threat. At the same time, our thalamus sends the information to the frontal lobes, the part of the brain which allows us to comprehend what just happened. Our amygdala processes information much faster than the frontal lobe, so when there is danger, we are able to act first and think later.
The thalamus helps us distinguish between information that is relevant and nonrelevant, acting like a filter to help us maintain concentration and focus. This function is weakened in those who have PTSD, which results in an overload of information. In order to manage this sensory overload, individuals will sometimes either shut down or numb through the use of substances (Van Der Kolk, 2015).
Brain scans have shown that when a traumatic event occurs, there is a decrease in activity in the Broca’s area, a subdivision in the neocortex that is located in the left frontal lobe. This is one of the areas of the brain responsible for speech. At the same time this is occurring, there is increased activity in the right part of the brain, which stores memories associated with sound, touch, and smell. Because of this, traumas are not stored in the brain as a clear storyline, with a beginning, middle and end. Rather, they are a series of memories which are primarily experiential: fragments of images, sensations, emotions, sounds, all of which evoke a sense of panic and terror when recalling the events of the trauma. This is why some people who experience trauma appear frozen and unable to speak.
Eye movement desensitization and reprocessing (EMDR) research currently hypothesizes that individuals who have PTSD have stored the trauma memory in their nervous system, storing the event in the exact same way it was first experienced (Shapiro, 2001). This is why, for example, a survivor of childhood sexual abuse can still experience the trauma many years later as if it was still happening to them. Brain scans conducted have documented this occurrence. When experiencing a flashback, the amygdala makes no distinction between the past and present; the body continues to respond to a trigger memory as if it is still happening, even if the trauma occurred years ago (Van Der Kolk, 2014).