Pure O Therapy London

What is “Pure O”? Understanding Mental Compulsions, Existential OCD and Hidden Rituals

Approx. 750+ words | Keywords: Pure O therapy London, existential OCD, mental compulsions, intrusive thoughts therapy

“Pure O” is a term often used to describe a form of OCD where the person experiences intrusive thoughts without obvious external rituals. Someone may not wash repeatedly, check locks, arrange objects or perform visible behaviours, yet they may feel trapped in relentless loops of thought. For this reason, Pure O can be confusing. It can look like overthinking, anxiety, philosophical questioning or relationship doubt, when in fact a compulsive cycle is often operating internally.

The phrase “purely obsessional” is therefore misleading. Most people described as having Pure O are not experiencing obsessions alone. They are usually engaging in mental compulsions. These are internal behaviours designed to reduce anxiety, achieve certainty, undo a feared meaning, or check whether the person is safe, good, real, in love, moral, sane or in control.

The compulsion may be invisible to others, but it functions in the same way as a visible ritual: it briefly reduces distress, then strengthens the obsession over time.

Mental compulsions can include rumination, analysing, reviewing memories, checking emotional responses, testing attraction, mentally comparing, praying, replacing “bad” thoughts with “good” ones, neutralising images, or searching for a feeling of certainty. A person may spend hours trying to answer a question that cannot be answered with absolute confidence. The problem is not that they have failed to think hard enough; the problem is that thinking itself has become the compulsion.

Existential OCD is one example of a Pure O presentation. A person may become preoccupied with questions such as “What if nothing is real?”, “What if I never feel present again?”, “What is the meaning of life?”, “What if I am trapped in my own consciousness?” or “How do I know I really exist?” These questions may sound philosophical, but in OCD they often become urgent, repetitive and distressing.

The person is not calmly reflecting on life’s mysteries; they are trying to resolve uncertainty in a way that the mind can never finally satisfy.

Other subtypes commonly associated with Pure O include relationship OCD, harm OCD, sexual orientation OCD, paedophilia-themed OCD, moral or scrupulosity OCD, and identity-based obsessions. The content varies, but the underlying structure is similar. A thought appears, the person interprets it as significant, anxiety rises, and they begin to mentally check, solve, disprove or neutralise it. The more they try to get certainty, the more important the thought feels.

Pure O is often missed because the compulsions are private. Someone may sit silently in a meeting, dinner or therapy session while internally reviewing whether they felt the “right” feeling, whether they meant something they said, whether they might harm someone, or whether their entire sense of reality is false. Because the suffering is hidden, people may feel ashamed, isolated or frightened that their thoughts reveal something terrible about them.

Traditional CBT with ERP can be very helpful, but it needs to identify the mental rituals clearly. If treatment focuses only on obvious behavioural avoidance, the internal compulsive loop may continue untouched. ERP for Pure O often involves exposure to uncertainty, feared thoughts, images or sensations while resisting the mental compulsion to analyse, reassure, check or neutralise. For example, in existential OCD, the exposure may not be to a physical place but to the presence of an unresolved question.

ACT can be especially useful here because it directly targets the relationship to thoughts. Instead of trying to prove that a thought is harmless, ACT helps the person notice the thought, allow uncertainty, and move attention towards chosen values. This can be powerful for Pure O because the goal is not to find the perfect answer; it is to stop living as though certainty is required before life can be lived.

Cognitive defusion, willingness and values-based action can help a person disengage from internal rituals without getting into another argument with the mind.

A psychodynamic perspective adds another dimension. It asks why this particular theme has become so charged. Why has the mind attached to morality, intimacy, harm, identity, reality or responsibility? What emotional conflict might the obsession be organising? What relational history might make uncertainty feel intolerable? From this view, Pure O is not meaningless mental noise. It can be understood as a symptom that may carry emotional meaning, even if the literal content of the obsession is not true.

This matters because people with Pure O often feel alienated from themselves. They may fear their mind, mistrust their feelings, or treat every internal event as evidence. Therapy can help separate the presence of a thought from the meaning the person has attached to it. At the same time, it can explore the deeper vulnerability that made that thought feel so dangerous in the first place.

I offer therapy for Pure O and OCD in London Bridge and online across London, including Soho, Shoreditch and Islington. My approach integrates ERP, ACT and psychodynamic therapy so that mental compulsions are addressed directly while the deeper emotional and relational context is also taken seriously.

References

• International OCD Foundation (n.d.) About OCD: Mental compulsions. Available at: https://iocdf.org/
• Williams, M.T. et al. (2011) ‘The myth of the pure obsessional type in obsessive-compulsive disorder’, Depression and Anxiety, 28(6), pp. 495–500.
• Lee, S.W. et al. (2023) ‘Is acceptance and commitment therapy effective for obsessive-compulsive disorder? A systematic review and meta-analysis’, Journal of Contextual Behavioral Science.