The amygdala plays a central role in the experience of psychological trauma. It is a part of the limbic system, which is responsible for survival-based responses to threat. The amygdala is primarily involved in processing emotions, especially fear and anxiety, and it is critical for generating emotional and physiological responses to stimuli.
Here is a breakdown of the amygdala’s role in psychological trauma:
- Encoding Traumatic Memories: The amygdala is a key structure in the encoding of traumatic memories. When a threat is perceived, the amygdala becomes activated, and a specific type of receptor, the AMPA receptor (AMPAR), is potentiated, which means that it is increased in number and permanence. This process is crucial for maintaining the traumatic memory.
- The Thalamo-Amygdala Pathway: The amygdala receives sensory information about potential threats directly from the thalamus. This pathway allows the amygdala to react quickly, even before the cortex has had time to process the information. This is why people can have an immediate fear response before they are consciously aware of a threat. The sense of smell, however, bypasses the thalamus and goes directly to the amygdala.
- Emotional and Physiological Response: The amygdala generates the emotional and physiological responses to perceived threats. It sends signals to the hypothalamus, which then triggers the release of stress hormones like cortisol and adrenaline. This results in increased heart rate, blood pressure, and breathing rate, preparing the body for fight or flight.
- Trauma Filter: When a traumatic event is encoded, it can create a “trauma filter” in the brain. This means that the amygdala may become hypervigilant, causing it to misinterpret situations as dangerous, even when they are not. This can lead to chronic stress and increased vulnerability.
- The Amygdala’s Role as Protector: The amygdala acts as a protector, constantly scanning the environment for potential threats. While the goal is protection, the amygdala can overreact, creating fear responses in situations that are not truly dangerous. This can lead to anxiety, panic, and other forms of distress.
- Emotional Memories: The amygdala stores emotional memories, which are not always consciously accessible. These memories are linked to specific objects, situations, or sensory inputs that were present during the traumatic event. When exposed to a trigger, the amygdala can reactivate the traumatic memory, resulting in a strong emotional and physical response, even if the cortex has no knowledge or memory of the initial event.
- The Amygdala and Pain: The amygdala can modulate pain signals arriving from other parts of the brain. During a fight, flight, or freeze response, the amygdala can inhibit pain perception. The amygdala can also be the location where chronic pain is stored. Somatic parts of a trauma, such as pain, can be stored in the brain and retrieved when exposed to related stimuli.
- Disconnection from the Cortex: In situations of high arousal, the amygdala can override the cortex, causing a “hostile takeover of consciousness by emotion”. This means that rational thought can be impaired, and emotional reactions become dominant. The amygdala can also influence the cortex through the release of chemicals that alter thinking.
- Impact on Behaviour: Trauma can lead to an overactive amygdala, which can cause a variety of behaviours, including anxiety, hyperarousal, hypoarousal, avoidance, and difficulty in social situations. It can also create rumination loops, where the individual dwells on negative thoughts and experiences. Additionally, the amygdala can influence the cortex by causing the release of chemicals that influence the entire brain, which can alter the way you think.
How to Manage the Effects of Trauma on the Amygdala
- Becoming an Amygdala Whisperer: It is possible to become aware of the amygdala’s activation and use self-talk strategies to manage it. This involves recognizing the amygdala’s role as a protector and using techniques to reduce its arousal.
- Havening Techniques: Havening allows for the depotentiation of traumatically encoded experiences in the amygdala. Havening targets the neurons holding traumatic experiences, empowering the brain to release these experiences and reducing their impact. Havening touch, when combined with the activation of a traumatic memory, generates a delta wave, which is associated with relaxation, and facilitates the depotentiation of the AMPA receptor. This process delinks the emotional content from other components of the trauma, diminishing the memory’s impact.
- Exposure Therapy: Through repeated exposure to triggers without negative consequences, the amygdala can learn that certain objects or situations are not actually dangerous. This process, known as exposure therapy, creates new neural pathways and reduces the fear response. The amygdala’s reliance on experience explains why talk therapy alone may not be sufficient.
- Vagus Nerve Stimulation: Stimulating the vagus nerve can calm the amygdala. The vagus nerve is the principal manager of the parasympathetic nervous system, which functions to calm the amygdala and move you out of fight, flight, freeze, or fawn mode.
- Mindfulness: Being mindful of the state of the mind and body when a trauma is triggered can create an opportunity for integrating the experience as a memory of the past, rather than a current event.
- Understanding the Language of the Amygdala: The amygdala’s language is based on associations, not logic. Understanding this can help individuals recognize that their reactions are often based on past experiences and not always a reflection of present reality.
- Lifestyle Changes: Exercise and adequate sleep can positively influence the amygdala, reducing stress and anxiety.
In summary, the amygdala plays a critical role in psychological trauma by encoding traumatic memories, generating fear responses, and creating a trauma filter that can lead to hypervigilance and emotional distress. However, with the right techniques, it is possible to manage the amygdala’s reactions, reduce its impact, and promote healing and resilience.