Understanding Somatic Flashbacks and Their Neurological Basis

What is a somatic flashback? Trauma is remembered not only as a story but also as isolated sensory imprints: images, sounds, and physical sensations that are accompanied by intense emotions. When these unprocessed sense fragments of trauma, such as sounds, smells and physical sensations, are triggered by similar sensations in the present, they can bring back aspects of the traumatic experience into consciousness, seemingly unmodified by time. Therefore, what is a somatic flashback can be understood as the re-experiencing of these physical sensations associated with a past trauma, often without the full narrative memory of the event. These bodily sensations can include pain, burning, temperature alterations, and tenderness.

When somebody experiences flashbacks, several things are going on in the brain. Brain scans have revealed that during flashbacks, the brain can light up predominantly on the right hemisphere, while the left hemisphere, responsible for organising experience into logical sequences and translating feelings into words (including Broca’s area), can become deactivated. The thalamus, which normally functions as a relay station integrating sensory information into autobiographical memory, can also become blanked out during flashbacks, explaining why trauma is often remembered as fragmented sensory imprints rather than a coherent narrative. Furthermore, the frontal lobe, including the region necessary for putting feelings into words and the region that creates our sense of location in time, may also shut down. In individuals with Post-Traumatic Stress Disorder (PTSD), flashbacks can involve the re-experiencing aspects of the traumatic events via intrusive thoughts and emotional distress in response to internal or external cues that serve as reminders of the trauma. These stimuli can trigger a re-experience of the trauma, heightened somatic activity, and behavioural manifestations of extreme terror. Brain imaging studies of people suffering from PTSD have also shown altered activation in areas associated with the default network, which is involved with autobiographical memory and a continuous sense of self. Additionally, there may be increased activity in the limbic system, basal ganglia, and anterior cingulate gyrus.

There are several plausible reasons why people develop flashbacks. Traumatic events can reset the brain to a perpetually more active state. Very high levels of cortisol at the time of the event have been suggested as a cause of a disrupted narrative memory, leading to dissociated memories possibly stored in procedural memory. These dissociated memories can then be triggered by present-day stimuli that are related to the encoding event. In people with smaller hippocampi (a brain region involved in memory and transmitting threatening events), which can be the case in individuals with a history of PTSD, child abuse, or violence, there is a belief that they conjure or create unwanted flashbacks of traumatic memories and struggle to put memories in chronological order. The amygdala, the seat of the fight-or-flight mechanism, plays a primary role in processing emotional reactions and can trigger stress responses based on past experiences, even if these represent “false alarms”.

Flashbacks have a significant impact on the brain. The persistence of traumatic memories as split-off, unmodified images, sensations, and feelings indicates a disruption in the normal processing and integration of these experiences. The deactivation of the left hemisphere during flashbacks impairs the capacity to organise experience logically, identify cause and effect, and create coherent plans for the future. Altered activity in the default network can affect the continuous sense of self. The increased activity in the limbic system and related areas contributes to a state of hyperarousal and heightened emotional reactivity. Over time, the repeated activation of these trauma-related neural pathways can reinforce them, potentially increasing the frequency and intensity of flashbacks if not addressed.

There are several things somebody can do to reduce either the severity or frequency of flashbacks, and various tools and techniques are available:

• Grounding Techniques: Calmly grounding oneself in the present moment can help to re-engage the frontal lobes of the brain. This can involve focusing on sensory details of the immediate surroundings, such as looking at the floor and noting the colour of the carpet.
• Reality Checking: If dissociation or a full flashback occurs, it can be helpful to use methods of reality checking, touch, and approaching the experience from an observer perspective rather than as a participant.
• Mindfulness and Acceptance: Developing a mindful and accepting posture towards the consequences of flashbacks, rather than trying to make them go away, can be beneficial. The problem is often the reaction to the flashback, not the flashback itself. Mindfulness exercises can help increase awareness of physical sensations and thoughts without judgment.
• Solution-Focused Brief Therapy (SFBT): While not directly targeting flashbacks, SFBT aims to increase positive emotions and focus on future solutions and past successes, which can indirectly help in managing distress associated with flashbacks. The miracle question (“Suppose a miracle happens tonight…”) can help shift focus towards a positive future.
• Acceptance and Commitment Therapy (ACT): ACT focuses on accepting difficult thoughts and feelings (like those arising during or after a flashback) and committing to actions aligned with personal values, which can reduce the struggle against these experiences.
• Havening Techniques®: These techniques use touch, attention, and imagination to trigger electrochemical changes in the brain, aiming to depotentiate the traumatically encoded experiences in the amygdala. Event Havening involves recalling the event while using Havening Touch to reduce the distress associated with the memory.
• Eye Movement Desensitization and Reprocessing (EMDR): This therapy involves bilateral stimulation (e.g., eye movements) while processing traumatic memories and associated sensations, aiming to integrate these memories in a less distressing way.
• Neurofeedback: This technique aims to intervene in the brain circuitry that promotes and sustains states of fear, shame, and rage associated with trauma, helping to change habitual brain patterns.
• Somatic Experiencing: This and other somatic healing approaches can help access and resolve body-based responses related to trauma that may contribute to somatic flashbacks.
• Working with Metaphors: If the mind is processing trauma through symbolism and metaphors, engaging with these can be powerful.
• Self-Compassion: Practising self-compassion can help reduce negative self-talk and emotional reactivity following a flashback.
• Understanding Triggers: Paying attention to what precedes a flashback (thoughts, feelings, situations) can help in identifying and potentially managing triggers.
• Reframing Thoughts: Examining and questioning the assumptions and impact of negative thoughts associated with the trauma and flashbacks can be helpful.

Summary

Somatic flashbacks are the re-experiencing of physical sensations linked to past trauma, often occurring without a full narrative memory. Neurologically, they involve heightened activity in the right brain hemisphere and limbic areas, while areas responsible for logical processing, verbalisation, and sensory integration may be deactivated. Flashbacks can arise due to the way traumatic memories are encoded and stored in the brain, particularly in the amygdala and hippocampus, and can be triggered by sensory reminders. They impact the brain by reinforcing trauma-related neural pathways and disrupting normal cognitive and emotional processing. Strategies to reduce their severity and frequency include grounding techniques, mindfulness, various psychotherapies like SFBT, ACT, Havening, and EMDR, as well as somatic approaches and self-compassion practices.