A common thread woven throughout trauma-related disorders is the phenomenon of dysregulation—the impairment in managing emotional and physiological states. Contemporary trauma theorists now widely regard dysregulation of arousal and affect as central to understanding the persistence of trauma symptoms (Van der Kolk, 2014). Individuals who have experienced trauma often struggle to maintain emotional stability, fluctuating unpredictably between states of hyperarousal (manifesting as anxiety, irritability, panic, or anger) and hypoarousal (characterized by emotional numbness, dissociation, and withdrawal) (Ogden et al., 2006; Siegel, 2012). Trauma essentially undermines the individual’s capacity to remain within the optimal emotional range known as the “window of tolerance” (Siegel, 2012), resulting in recurrent cycles of emotional extremes.
The neurobiological basis of dysregulation can be traced back to early disruptions in caregiving relationships, chronic stress, or traumatic events that overwhelm the brain’s regulatory capacities. Specifically, trauma interferes with the normal functioning of brain regions involved in emotional modulation, such as the prefrontal cortex, amygdala, and hippocampus, leading to chronic overreactivity or underresponsiveness in emotional processing (Teicher & Samson, 2016). For instance, individuals with trauma histories typically show increased amygdala activity coupled with diminished prefrontal inhibition, a neural profile that supports heightened emotional reactivity without adequate regulation (Rauch et al., 2006).
In cases of developmental or complex trauma, dysregulation is particularly pronounced and pervasive. Children exposed to ongoing relational trauma or neglect fail to develop essential self-soothing mechanisms and effective neural circuitry needed for stable emotional regulation (Schore, 2003). Such individuals are prone to severe and chronic dysregulation, often exhibiting dramatic swings from emotional explosiveness to emotional numbing as survival strategies in the absence of reliable caregiver regulation (Perry, 2009). This persistent emotional dysregulation underlies numerous secondary symptoms, such as self-harm, substance abuse, dissociative episodes, and relational instability, reflecting maladaptive attempts at managing overwhelming internal states (González, 2012; Linehan, 1993).
Van der Kolk (2014) emphasizes that individuals with trauma histories frequently possess limited control over their emotional responses. Their physiological fear reactions are easily triggered by minor stimuli, with insufficient frontal lobe modulation to mitigate intense emotional states. Such neural imbalances explain clinical phenomena like exaggerated startle responses, emotional volatility, and vulnerability to being overwhelmed by even mild stressors.
Moreover, physiological dysregulation associated with trauma extends beyond emotions to broader autonomic nervous system disruptions. Traumatized individuals often experience irregular oscillations between sympathetic hyperactivation (manifested as anxiety, rapid heartbeat, sweating, and panic) and parasympathetic hypoactivation (characterized by lethargy, numbness, or dissociation) (Porges, 2011). Children and adults with complex trauma histories may exhibit atypical sensory responsiveness—either heightened sensitivity to external stimuli or diminished responsiveness to sensory inputs, indicative of profound body dysregulation (Van der Kolk, 2014).
At a neurochemical level, trauma can produce significant dysregulation within neurotransmitter systems, including alterations in cortisol patterns, norepinephrine, and dopamine levels. For example, chronic trauma exposure often results in disrupted cortisol rhythms—either elevated due to ongoing stress or paradoxically reduced due to adrenal exhaustion—contributing to ongoing difficulties with emotional and physiological self-regulation (Yehuda et al., 2006).
Clinically, dysregulation serves to perpetuate trauma symptoms, as individuals struggle to manage overwhelming internal experiences, frequently resorting to maladaptive coping strategies such as substance abuse, self-injury, or interpersonal aggression (Linehan, 1993). Treatment approaches to trauma invariably prioritize establishing greater regulatory capacity. Early stages of trauma therapy thus emphasize skills for grounding, breathwork, mindfulness, and somatic awareness—techniques designed to stabilize emotional and physiological arousal (Ogden et al., 2006). Daniel Siegel’s concept of expanding the “window of tolerance” is widely applied, emphasizing gradual enhancement of affective tolerance and neural integration (Siegel, 2012).
Because relational dysregulation typically originates in disrupted early attachment, modern trauma therapies emphasize the therapeutic relationship itself as a key regulatory mechanism. Therapists provide co-regulation, using attuned, empathic interactions to model and foster internalized capacities for emotional modulation in their clients. Over time, consistent relational stability in therapy can help recalibrate the client’s dysregulated autonomic and affective systems, promoting greater self-regulatory capability and emotional flexibility (Schore, 2012).