Mian Li Ong, PhD

Lightfull Psychology is my solo private practice in central Singapore, offering assessment and evidence-based treatment for OCD and related disorders across the lifespan, from children through adults. Roughly 25% of my practice focuses on OCD, body-focused repetitive behaviors such as trichotillomania and excoriation, and tic disorders, primarily through exposure and response prevention (ERP) and habit reversal. These often co-occur with ADHD, anxiety, and twice-exceptional profiles, which I treat together rather than in isolation. Across more than a decade of clinical work in the United States and Singapore, I have treated over 100 individuals with OCD or a related disorder.

Co-occurring conditions are the norm in my practice, so I begin with a functional case formulation that maps how the conditions interact and what is driving what. Sequencing follows from that: I prioritize whichever problem is most debilitating or is functionally driving the others, rather than following a fixed diagnostic order. ERP anchors OCD treatment, but I adapt it: with co-occurring ADHD I scaffold exposure with executive-function support, and with tic disorders I distinguish urge-driven behaviors from obsession-driven compulsions and apply CBIT or ERP accordingly. When indicated, I coordinate medication with the prescribing psychiatrist.

I am a licensed clinical psychologist registered with the Singapore Register of Psychologists. I completed my PhD in clinical psychology at UNC and a postdoctoral fellowship at Mayo Clinic, both grounded in cognitive behavioral and exposure-based treatment. I am trained in Comprehensive Behavioral Intervention for Tics (CBIT) and habit reversal, which I apply to tic disorders and body-focused repetitive behaviors. I have treated individuals with OCD and related disorders for 10 years across academic medical centers, psychiatric hospitals, and private practice. Supervisors are at Mayo Clinic, UNC-CH, and at UTHSCSA.

My practice is based in Singapore, one of the most ethnically and linguistically diverse societies in the world, and serves clients across its major communities (Chinese, Malay, Indian, and Eurasian) alongside a substantial international expatriate population. Clients span the lifespan and a wide range of national, cultural, and linguistic backgrounds. Presentations of OCD and related disorders frequently intersect with culturally specific beliefs, family structures, and expressions of distress, which I account for in assessment and treatment.

My clinical training was completed in APA-accredited programs in the United States, where multicultural competency and work with diverse populations are a core training requirement, and I have since practiced for several years within Singapore’s multiethnic, multireligious, and multilingual context. This has meant routinely adapting evidence-based care across differing cultural understandings of mental health, stigma, and family involvement. I also work from a neurodiversity-affirming stance, treating neurodivergent identity as a further dimension of diversity in OCD and related-disorder care.