RecruitingDevice studyOCD LIFU Target EngagementThe investigators will conduct a pilot study to evaluate the safety and feasibility of low-intensity focused ultrasound on obsessive-compulsive disorder (OCD) symptoms when delivered to subcortical brain targets. The investigators will use the ATTN201 device to deliver single sessions of unfocused and focused ultrasound to up to three brain targets over 4 study visits and assess the intervention through self-rated scales of OCD symptoms.