BACKGROUND AND IMPORTANCE: Deep brain stimulation (DBS) is an effective treatment for patients with refractory neuropsychiatric disorders. Along with symptom improvement, DBS may have concurrent behavioral effects that help to unravel the role of specific brain circuitries in complex human behavior. CLINICAL PRESENTATION: This article reports on 2 patients with obsessive-compulsive disorder who received DBS targeted at the nucleus accumbens that resulted in a temporary change of accent and use of vocabulary. CONCLUSION: Changes in accent and speaking manners are most likely related to direct DBS stimulation effects of the electrode targeted at the nucleus accumbens. The shift in accent, resembling foreign accent syndrome after injuries in brain language centers, has not been reported before in the course of DBS. Induction of aggressive vocabulary may be related to transient hypomanic behavior after DBS. ABBREVIATIONS: DBS, deep brain stimulationFAS, foreign accent syndromeNAc, nucleus accumbensOCD, obsessive-compulsive disordervALIC, ventral part of the anterior limb of the internal capsule.