Sensory trauma occurs when the nervous system becomes dysregulated through traumatic experiences. The brain and body develop heightened sensitivity to sensory input—sounds, touch, light, smell, and taste—as a protective mechanism. This hypervigilance, while initially adaptive, can become overwhelming and interfere with daily functioning. Understanding how trauma affects sensory processing is essential for recovery, as it allows survivors and professionals to recognize nervous system responses and implement targeted interventions.
Activated during perceived threat, the sympathetic nervous system prepares the body for action. This system increases heart rate, blood pressure, and muscle tension.
Physical Signs:
The parasympathetic nervous system promotes relaxation and recovery. It lowers heart rate, aids digestion, and supports immune function. This is the system we want activated for healing.
Physical Signs:
In trauma survivors, the nervous system often becomes "stuck" in a state of hyperarousal (sympathetic activation). The brain learns to interpret neutral stimuli as threats, causing the nervous system to remain in a protective state even when danger has passed. This dysregulation is not a choice or weakness—it's a neurobiological response to overwhelming experiences. Recovery involves helping the nervous system recognize safety and return to baseline regulation.
Normally, the brain filters out irrelevant sensory information—a process called "sensory gating." This allows us to focus on important stimuli while ignoring background noise. In trauma survivors, this filtering mechanism becomes impaired. The result is sensory overload: every sound seems loud, every touch feels intense, and the nervous system cannot distinguish between safe and dangerous stimuli.
Example:
A survivor hears a car backfire and experiences a full panic response—increased heart rate, difficulty breathing, and intrusive memories—even though they logically know they're safe. Their nervous system has learned to interpret this sound as a threat.
The amygdala is the brain's emotional processing center and threat detector. In trauma survivors, the amygdala becomes hyperactive and hypersensitive. It learns to associate neutral stimuli with danger, triggering fear responses to everyday situations. This hyperactivity is reflected in increased amygdala volume and heightened activation patterns observed in neuroimaging studies.
Connection to Sensory Trauma:
When the amygdala is hyperactive, sensory information is rapidly processed as threatening before the thinking brain (prefrontal cortex) can evaluate whether there's actual danger. This explains why sensory triggers can cause immediate, involuntary panic responses.
The prefrontal cortex is responsible for rational thinking, decision-making, and emotional regulation. In trauma survivors, this region shows reduced activation and connectivity with the amygdala. This means the "thinking brain" has reduced ability to calm the "alarm brain," allowing fear responses to dominate.
Connection to Sensory Trauma:
Even when a survivor knows logically that they're safe, the weakened prefrontal cortex cannot override the amygdala's threat response. This is why trauma recovery requires more than "thinking positively"—it requires rebuilding neural pathways and nervous system regulation.
When the nervous system detects a threat (real or perceived), it activates the HPA axis (hypothalamic-pituitary-adrenal axis), releasing stress hormones like cortisol and adrenaline. In trauma survivors, this system becomes dysregulated, leading to either excessive cortisol production (hyperarousal) or insufficient cortisol (hypoarousal).
Connection to Sensory Trauma:
Dysregulated stress hormones intensify sensory sensitivity. High cortisol levels increase pain sensitivity and auditory sensitivity, while low cortisol can cause numbness and dissociation. Understanding this connection helps explain why sensory symptoms fluctuate.
Recovery from sensory trauma involves helping the nervous system recognize safety and rebuild its capacity for regulation. This process takes time and requires a multi-faceted approach.
The brain's ability to form new neural pathways—neuroplasticity—is central to trauma recovery. Through repeated practice of regulation techniques, survivors can literally rewire their nervous system. The amygdala becomes less reactive, the prefrontal cortex strengthens its connections, and the nervous system learns to recognize safety. This process takes time and consistency, but recovery is possible.
Beyond traditional trauma, children today face emerging neurobiological threats from technology and digital media. Fair Play for Kids research documents how AI toys, social media algorithms, and exploitative tech practices create psychological harm during critical developmental periods.
AI companions designed for young children use the same addictive technology that has harmed adolescents. These devices can dysregulate developing nervous systems through constant digital stimulation.
Meta Instagram algorithm exposes teens to content promoting suicide, self-harm, and eating disorders. The platform facilitates grooming and exploitation.
Fair Play for Kids partners with families who have lost children to social media harms. These parents advocate for KOSA to hold tech companies accountable.
Learn More About Fair Play for Kids