Cognitive Behavioural Therapy - CBT for Pure "O" OCD - London, Kent, Surrey, Poole and Online by Video Link

If you are continuously struggling with intrusive, persistent and highly distressing thoughts, doubts, memories or mental images, you may be suffering with Primarily Obsessional OCD. This  is also commonly known as Pure “O” OCD. 

We provide specialist treatment for Pure “O” OCD, using evidence based cognitive and behavioural strategies from the fields of CBT, ACT, IBT and an adapted form of Exposure and Response Prevention (ERP). 

Whilst the published research shows that there are many similarities between Pure “O” and other OCD subtypes, the CBT and ERP process is adapted to target the internal mental processes that maintain the problem. This requires the support of an experienced and professionally qualified OCD expert.

We find that many of our OCD clients come to us having struggled with highly distressing thoughts over many years, or where other types of counselling or psychotherapy have been found to be ineffective in the treatment of Pure “O” OCD. To book an initial intro call with a Pure “O” specialist, you can email This email address is being protected from spambots. You need JavaScript enabled to view it. or complete our contact form.

What is Pure "O" OCD?

The term Pure “O” OCD was first  used by  Dr Steven Phillipson from the Centre for Stress and Anxiety Management in 1991. Based on many years of first hand experience working with OCD patients, Phillipson described an internal or mentalised form of OCD, involving persistent and distressing intrusive thoughts, which he called “Spiking”, followed by attempts to control the intrusions through the mental process of rumination. 

Whilst it was initially believed that this form of OCD did not involve observable compulsions, Phillipson identified internal attempts to stop, check, avoid, neutralise or control intrusive thoughts and doubts through internal mental compulsions. Pure “O” is therefore understood as an internal or covert form of OCD, in which the compulsions are internal mental acts to prevent or avoid the distressing intrusions and related obsessional worries. The term Pure “O” should therefore be seen as a shorthand label for describing an internalise form of OCD, where the spike, the obsession and the compulsion are primarily internal mental processes.

How is Pure "O" OCD Maintained?

Like all other OCD subtypes, Pure "O" OCD involves a three-part interconnected process. Intrusive doubts lead to intense obsessions and high levels of anxiety and depression. Mental Compulsions are performed in an attempt to neutralise or suppress the obsessions and anxiety. Whilst the mental compulsions provides temporary relief, this also reinforces the vicious cycle of Pure "O" OCD.

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Unlike other forms of OCD however, the compulsions are primarily internal mental acts or routines and difficult to externally observe. The line between obsessions and mental compulsions is therefore frequently blurred and difficult to distinguish.

The Pure "O" Cycle

The trigger or intrusion phase involves a preoccupation with unwanted, persistent and highly distressing thoughts, memories or images. These Pure “O” spikes activate the primary OCD doubt. Primary doubts can be internally generated irrational thoughts about safety, security, symmetry, danger, threat, responsibility or losing control. 

If left unchecked, primary doubts cross over from normal every-day doubts, into internally generated and imagined doubts that are highly irrational, defy direct experience and undermine the individual’s own integrity and common sense. This leads to the second phase of obsessional worry. 

The second phase in the Pure “O” loop involves obsessional worry, over-analysis, fixation, rumination, cognitive distortion, Perfectionistic thinking and high levels of emotional distress. The individual becomes entangled and embroiled in a relentless struggle with their own thoughts, losing the distinction between observable, testable and  rational threats versus internally imagined or hypothetical possibilities. Obsessions paradoxically revolve around issues that are highly important or sensitive to the individual. This can include obsessional worry about:

Obsessional worry leads to a desperate and urgent need to disprove or eliminate all feelings of uncertainty or  discord, by compulsively testing, checking, stopping, neutralising, controlling or  avoiding the obsessional thoughts. 

The Pure “O” Compulsion involves internal compulsions to mentally avoid, stop, control, resist, deflect, neutralise or outthink the distressing intrusions. Typical mental compulsions include:

These desperate attempts to disprove, escape or control the distressing intrusions, paradoxically lead to increased levels of hypervigilance,  doubt, preoccupation and rumination. This creates and maintains a Pure “O” vicious cycle, in which the individual’s attempts to avoid or stop the unwanted thoughts, fuels increased levels of preoccupation, doubt and mental resistance. 

Over time, this vicious cycle becomes automatic and  reflexive. The trigger becomes synonymous with the primary doubt, creating automatic mental associations and increasing the individual’s sensitivity and hypervigilance to the problem. 

In Pure “O” OCD, magic numbers or words therefore become associated with the probability of something bad happening, testing memory or replaying past events becomes associated with doubting memory, mantras, compulsive praying or mental repetitions, become associated with illness, bad luck or danger.

The Difference Between the Pure "O" Intrusion, Obsession and Mental Compulsion

As Pure “O” OCD is primarily an internal mentalised process, it’s often difficult to separate the intrusions, irrational doubts and  obsessions from the mental compulsions . Terms such as intrusion, doubt, worry and rumination are used on an interchangeable basis to describe internal mental processes, without accurately distinguishing between the Pure “O” doubts, obsessions and mental compulsions. 

This distinction is however important to effective and targeted psychological therapy. Understanding where the intrusive doubts and obsessions finish and where the mental compulsions begin, is relevant to the effective application of CBT, ACT, IBT and ERP. 

To understand the difference between the Pure “O” intrusive doubts, obsessions and mental compulsions, we must first identify the intention or function behind the behaviour at each stage of the Pure “O” cycle.   

The Psychology of Intrusions and Doubts    

In Pure “O” OCD, individuals are triggered by situations or intrusive thoughts that are repugnant and distressing.   This is maintained by selective focus of attention, problems with confirmation bias and conditioned association between the mental compulsion and the intrusive thought or doubt.   Rather than being rationally dismissed or filtered as random unwanted thoughts, Pure “O” intrusions activate underlying personal doubts about safety, security, responsibility, integrity and self-control. Therapy should therefore address focus of attention errors, problems with conditioned associations and confirmation bias.    

The Psychology of Pure “O” Obsessions 

All human obsessions are fundamentally rooted in an evolutionary need to maintain hypervigilance and flag potential threat, disorder, vulnerability or loss. This is part of a hard-wired  protective / learning mechanism for scanning our environment, ensuring survival, readiness and competitive advantage. In all forms of OCD, obsessional thinking crosses the line between the rational appraisal of probable external hazards, into the irrational misappraisal  and escalation of internally imagined or hypothetical risks. Obsessions involve problems with faulty and distorted thinking processes, misappraisal and misattributions and disproportionate and catastrophic evaluations. Rather than acting as a protective and adaptive learning mechanism, OCD obsessions are Egodystonic, distort reality and lead to excessive psychological distress. From a Pure “O” treatment perspective, it’s therefore important to focus on altering and de-escalating the faulty thinking processes that maintain obsessions and lead to distress. This includes addressing obsessional factors including responsibility bias, thought action fusion, perfectionistic and catastrophic thinking. This is covered in the section on the therapy process. 

The Psychology of Pure “O” Mental Compulsions 

Pure “O” OCD compulsions are a maladaptive response to perceived threat, loss or the exploitation of potential advantage. Whereas Pure “O” obsessions are about searching for potential threats, mental compulsions are about preventing, avoiding, controlling or  neutralising the obsessional distress.    

In spite of their egosyntonic intentions, Pure “O” OCD compulsions take up significant time and energy, prevent the disconfirmation of the feared situation, feed vulnerable and low coping  beliefs, create conditioned associations with irrational doubts and lead to significant functional impairment. From a Pure “O” treatment perspective, it’s therefore important to identify and understand the internal mental actions taken to avoid or alleviate perceived threat and distress. Here, the objective is to   expose, suspend, eliminate, learn, challenge, alter or use alternative and adaptive behavioural strategies, to the Pure “O” compulsion. Whilst it’s important to identify the Pure “O” obsession and mental compulsion using a process known as functional analysis and formulation, it is also important to recognise that individuals suffering with Pure “O” often think and respond in a seamless chain. This means that worry or rumination can be part obsession and part compulsion, depending on the context and function of the behaviour. 

From a therapy viewpoint, your therapist should have the qualifications, skills and clinical experience to understand and guide you through this process in a practical and relatable manner. Working with a properly qualified, skilled, experienced and accredited therapist will help you to develop an understanding of each stage of the Pure “O” process, identify the cognitive processes and behaviours that maintain the problem and most importantly, learn new techniques for tackling the Pure “O” doubt, the obsessional thinking and mental compulsions.

How is Pure "O" OCD Treated?

In the UK, the recommended treatment of choice for Pure "O" OCD is Cognitive Behavioural Therapy. This includes an adapted form of ERP, a specialist cognitive approach known as Inference Based Therapy (IBT) and strategies from Acceptance and Commitment Therapy (ACT).

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The Assessment and Treatment Process

The psychological assessment and treatment process for Pure "O" OCD typically involves 8-12 therapy sessions, when delivered by a qualified and experienced OCD specialist. This will always depend on the level of complexity and any other psychological or developmental factors identified during the initial assessment.

At Good CBT we draw upon the current evidence base to combine mainstream Cognitive Behavioural Therapy, including Exposure and Response Prevention (ERP), with a specialist form of CBT known as Inference Based Therapy (IBT). Strategies from Metacognitive Therapy and Acceptance and Commitment Therapy (ACT), are also integrated where relevant. The treatment plan normally includes:

The therapy process may also be supported by behavioural activation, behavioural experiments and mindfulness based exercises to improve mood, alter maladaptive beliefs and improve focus of attention skills. We also work closely with our Consultant Psychiatrist and we can organise medication assessments and reviews where appropriate.

following the initial assessment you will receive a written report, detailing the psychological factors that trigger and maintain the problem and an outline of the therapy plan. Appointments are normally held on a weekly basis and include a full 60 minute session, with a structured agenda, discussion, techniques and agreed practice activities. To find out more about the therapy process and to book an initial informal call, email This email address is being protected from spambots. You need JavaScript enabled to view it.or complete our contact form .