Question: Why is your sleep so bad after a life-threatening, or traumatic event?
Answer: Your survival brain remains stuck in protecting you from harm.
How does trauma overwhelm sleep? Your brain has many specialized areas, each with particular jobs they do for you. There is the thinking brain (cortex) which thinks through problems to find solutions. There is the emotional brain (limbic system) that provides quick action strategies (emotional responses) to move toward (or away) from positive (or negative) experiences. And below both of those there is the survival brain (autonomic system) in the brainstem.
The survival brain is in charge of keeping you alive. If anything
threatens your life or security, the survival brain takes charge.
What does “taking charge” mean? Taking charge means that the brainstem changes how the other, higher levels of the brain work. This shift in how they operate is called neuromodulation. Neuromodulation of the survival brain means that the alarm system that has detected danger STAYS ON. If you have seen a lion, the survival brain will not let go of this threat. It keeps repeating, “Where is the lion?” so you don’t get surprised and then eaten.
Neuromodulation of the emotional brain means that the negative defensive responses of terror, shame, rage, and aversion are heightened. Positive emotions of joy, curiosity, and connectedness evaporate when survival is in doubt.
Neuromodulation of the thinking brain means that the cognitive responses of rumination, worry, self-criticism, and catastrophizing are heightened. The thinking brain remains stuck on the thought, “Where is the lion?” Normal, balanced, problem-solving thought evaporates.
Where is the survival brain located? This diagram spotlights the survival brain. It is located in the brainstem, a dense area of interconnected nuclei all supporting each other to keep the alarm system ON. The heart of the alarm system is the Locus Coeruleus (LC). It activates the nearby Nucleus Gigantocellularis (NGC), the hub of the Reticular Activating System (RAS), and the Orexin-Thyroid system located in the Lateral Hypothalamus (LH). When all three of these clusters are activated, the resulting hyperarousal recruits other nearby brainstem nuclei. As the diagram shows, these nuclei overwhelm the sleep drive, which is usually activated by the Ventrolateral Preoptic Area (VLPO). The result of hyperarousal is a cycle of constant anxiety, tension, worry, broken sleep, and increasingly desperate fatigue, distress, and brain fog.
What can you do to reverse this hyperarousal? There are many steps to retraining the brainstem centres that are disrupting sleep. These are detailed in Putting Trauma to Sleep, which sets out a Sleep Informed Trauma Treatment with the TABS model. TABS empowers patients by understanding what is happening in the brain, and then giving patients and their therapists, the background knowledge, tools, and strategies to overcome these treatable sleep disturbances. If you are ready to start this process, please download the Breathing Assessment form. This will guide you to find your current breathing pattern. From there you can apply the steps highlighted in Chapter 4 of Putting Trauma to Sleep.