When we think about OCD, the spotlight usually falls on intrusive thoughts or repetitive rituals. But in many patients, the true “engine” of compulsive behavior lies deeper—in sensory phenomena (SP). These subtle, often overlooked experiences are now central to how ICD-11 conceptualizes obsessive–compulsive disorder.

What Are Sensory Phenomena?

Sensory phenomena are subjective experiences that precede or accompany compulsions. They are not thoughts in the traditional sense, but rather felt experiences that demand action. The main types include:

• Physical sensations: uncomfortable feelings in the skin, muscles, or joints (e.g., an itch-like drive to touch or adjust).

• “Just-right” perceptions: the sense that something must feel, look, or sound correct before one can move on.

• Feelings of incompleteness: a nagging inner sense that something is unfinished or imperfect.

• Energy release: a build-up of internal tension that only a repetitive act can discharge.

• Urges only: a blunt, compelling “have to do it” feeling, without accompanying thoughts.

These experiences can drive patients to repeat rituals even when no obvious obsession is present.

What the Research Shows

The Brazilian Research Consortium on Obsessive–Compulsive Spectrum Disorders, studying over 1000 patients, revealed that:

• 60% of patients endorsed some form of sensory phenomena

• Patients with Tourette’s syndrome or chronic tic disorder were even more likely to report SP, particularly physical sensations and pure urges.

• The most common SP across all groups were “just-right” perceptions—showing how central this feeling of incompleteness is to the OCD experience.

• Severity of SP was greatest in OCD with Tourette’s, suggesting overlapping neural pathways between tics and compulsions.

These findings show that SP are not rare curiosities—they are core features of OCD, cutting across subtypes.

Why Sensory Phenomena Matter

For clinicians:

• Diagnostic clarity: A patient who denies classic obsessions but reports “just-right” feelings may still meet criteria for OCD.

• Treatment tailoring: SP-driven compulsions may respond better when ERP (Exposure and Response Prevention) is combined with habit reversal training, a strategy also used in tic disorders.

• Phenomenological nuance: Recognizing SP helps avoid misdiagnosis as impulse-control disorders or stereotypic movement disorders.

For patients and families:

• It validates the lived experience. Many struggle to explain why they repeat actions “until it feels right.” Naming these sensations reduces stigma and fosters self-understanding.

Bridging Science and Subjectivity

SP illustrate how OCD is not just about fear of contamination or intrusive thoughts—it’s about the embodied sense of tension and relief. A purely cognitive model of OCD misses this layer; ICD-11’s expansion corrects that oversight.

By acknowledging sensory phenomena, psychiatry moves closer to describing OCD as patients truly experience it: a disorder of both thought and sensation, cognition and body.

About the Author

I’m Dr. Srinivas Rajkumar T, MD (AIIMS, New Delhi), Consultant Psychiatrist based in Chennai. Through my clinical practice and writing, I aim to make psychiatry more understandable and less intimidating.

📍 Mind and Memory Clinic, Apollo Clinic, Velachery, Chennai (Opp. Phoenix Mall)
📞 +91 85951 55808
🌐 srinivasaiims.com