Introduction
Exposure therapy, a cornerstone in treating trauma and anxiety, traditionally utilizes virtual reality (VR) to confront patients with their fears in a controlled, immersive environment. However, mixed reality (MR) can actually be more beneficial as it blends real-world elements with virtual overlays. Understanding VR and MR
At its core, VR immerses users in a completely fabricated digital environment, isolating them from the real world. This total sensory eclipse allows therapists to control every aspect of the environment, which can be crucial for initial exposure treatments. Conversely, MR introduces digital elements into the real-world view, maintaining the user's connection to their actual surroundings. This subtle yet profound difference sets the stage for a more grounded and potentially transformative therapeutic experience.

Theoretical Framework: Predictive Coding and Trauma
Predictive coding theory suggests that the brain continuously makes predictions about incoming sensory information based on past experiences. Trauma can profoundly influence the brain's cognitive processes, often establishing strong top-down biases that detach from bottom-up sensory information. This disconnection can be seen as a protective mechanism, where the few neurons take the brunt while the rest are protected from the traumatic perception. However if there isn’t an integration process to heal trauma these top down neurons which dissociated can lower the threshold of firing until even minor, non-threatening stimuli can activate them. This is because these neurons want to stay alive and require activation to do so but have no ability to change their prediction as they were dissociated.

Mixed Reality Is Better
In the context of trauma therapy, Mixed Reality can uniquely modify these predictions by merging real-time sensory data with traumatic memories. This allows for a dynamic reprogramming of traumatic responses, where the presence of actual sensory input serves to validate and activate the top down dissociated network while also connecting them to the bottom up current experiences.

Example in Childhood Trauma
In the context of childhood trauma, mixed reality (MR) can be extraordinarily effective by visually emphasizing the size difference between an adult and a child as experienced during the traumatic event. This application of MR allows patients to safely revisit traumatic memories within the context of their current environment. Imagine an MR scenario where an adult patient is presented with a virtual overlay that accurately represents the towering figure of an adult from their childhood perspective while overlaid on the real world. A figure that is 5 or 10 times as big as the adult overlays the current space. This visual manipulation helps the patient understand the significant size disparity that existed during their childhood trauma. This stark contrast between their past and current physical stature is made evident through MR, reinforcing the fact that as an adult, they now possess a larger body helping the dissociative bias update its knowledge about the current body.

Updating Trauma Biases To A Step Function
With Mixed Reality overlays a sharper differentiation between contexts that should trigger a trauma response and those that should not is possible. If I ever encounter an angry giant that is 5 to 10 my size grabbing me my childhood trauma response is indeed the best fitting prediction but for all other bottom up info a different top down predictions are actually a better fit and by using Mixed Reality overlays one can learn to increase the threshold of these top down trauma predictions by playing with the trigger threshold while being in a safe space (a professional might be necessary). Looking at the trigger in Mixed Reality and then looking at the background, looking at your body, feeling your feet on the ground can help a lot more than just looking at the trigger in Virtual Reality.