Regulating Emotional Intensity Through Language: A Mechanistic Case Study of Code-Switching in Prolonged Exposure Therapy

Abstract

Posttraumatic Stress Disorder (PTSD) remains one of the most debilitating anxiety disorders, with high prevalence, significant functional impairment, and disproportionate impact on minoritized groups. Although Prolonged Exposure Therapy (PET) is considered a gold-standard treatment, its effectiveness is limited by high dropout rates, particularly among Latine clients, who are historically underrepresented in PET research and implementation. Bilingualism influences emotional processing, with first language often eliciting heightened affective intensity during trauma recall. Building on this evidence, the present case study examines the integration of guided code-switching into PET (CS-PET) as a culturally responsive adaptation aimed at improving engagement and reducing distress among bilingual clients. “Julia,” a bilingual Latina survivor of childhood sexual abuse, who presented with PTSD symptoms. Standardized assessments confirmed a diagnosis of PTSD with delayed expression. Treatment followed a modified PET protocol that incorporated structured language switching based on Subjective Units of Distress (SUDS). Spanish, the language of the traumatic events, elicited greater emotional activation, whereas English provided a regulatory function. Guided code-switching allowed for sustained exposure while modulating distress. Over six treatment sessions, Julia demonstrated substantial reductions in PTSD, anxiety, and depressive symptoms, ultimately no longer meeting diagnostic criteria for PTSD at termination. This case highlights the potential utility of code-switching as an arousal-modulation strategy within exposure-based treatments for bilingual clients. Clinical implications include the importance of assessing language-related emotional processing, collaboratively establishing code-switching thresholds, and monitoring language shifts to preserve therapeutic fidelity. Future research should evaluate the generalizability and mechanisms of CS-PET.