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Rethinking the Unthinkable

by Steven J. Phillipson, Ph.D.
Center for Cognitive-Behavioral Psychotherapy


In 1989, Dr. Steven Phillipson coined the term "Pure-O" in his groundbreaking
article Thinking the Unthinkable. Pure-O is the subset of OCD whereby sufferers
engage in non-observable rituals to escape, avoid, or undo the emotional
distress associated with intrusive thoughts (e.g. spikes). 

The following article was originally published in the OCD Newsletter in 1991. Back then, behaviorists were still telling people with the Pure-O form of OCD (where the sufferer experiences obsessions only), that they hoped medication would be of some benefit. To their knowledge, there were no known methods of treatment that reliably produced positive outcomes with this form of OCD. In 1987, I had developed a highly structured and formalized behavioral method of treating this form of OCD. These treatment guidelines were derived from current strategies, proposed by Dr. Edna Foa, for the treatment of the more traditional forms of OCD (e.g. contamination and checking). Specifically, the strategy called Exposure and Response Prevention (E&RP), entails the practice of having the patient voluntarily come in contact with the feared items or situations, and then manage the pursuant anxiety while not performing the undoing response. The adaptation of E&RP for the Pure-O required a few modifications, but essentially retained the same empirically-based treatment model. Initially, the duration of treatment for the Pure-O was significantly longer (two years), than the duration of the traditional treatment of OCD (six months to one year). Using the adaptation model of treating the Pure-O form, the success rate was achieved well into the 70% to 90% range. This was comparable to Dr. Foa’s findings. In the mid-1990’s, Mark Frearston, Ph.D. published one of the first controlled studies for the treatment of the Pure-O, using very similar methods to those proposed by my 1991 article. His methodology relied on a much stronger cognitive component than my approach, which, as discussed below, have retained a much stronger behavioral component. Cognitive treatment for anxiety disorders relies on helping people identify the irrational nature of their fears and find the evidence of their irrationality. My work with thousands of patients has lent strong support to the idea that the cognitive element is not nearly as important as the more strict behavioral element, which focuses on providing effective strategies for managing the threatening ideas, rather than debunking the specific irrationality of the idea. At this point (2004), I am finding that, with some slight innovations that I have laid out below, there are no differences in the treatment duration (approximately six to twelve months) for people with Pure-O and those with the compulsions of the more traditional form of OCD.


In my conceptualization of Obsessive-Compulsive Disorder, the tree of the overall syndrome has three main branches: the "obsessive-compulsive," the "responsibility O-C," and the purely obsessional thinker ("Pure-O"). In “Pure-O”, the anxiety emerges in response to an unwanted, intrusive thought or question; what I call a "spike." The ritual or compulsion with this form of OCD involves the non-observable, mental ‘pushing away’ of the thought, avoiding the recurrence of the thought, or attempting to solve the question or undo the threat that the thought presents. It should be remembered that most people who come into therapy tend to have a combination of these three distinct forms of OCD. Successfully treating one form typically has minimal effect on the others. When persons present with more than one form of OCD, treatment will tend to initially focus on the observable rituals, since they are generally easier to treat and provide a positive momentum for further therapeutic work.

The "Pure-O" has two parts: the originating unwanted thought (spike), and the mental activity in which the sufferer attempts to escape, solve, or undo the spike. This is called “rumination.” With “Pure-O”, it is the threatening, nagging, or haunting nature of the idea, which compels the patient to engage in an extensive effort to escape from the thought. Most likely, it is not the intrusive idea, per se, that drives the response, but the associated emotional terror. The following are some illustrations of these types of “Pure-O” situations.

1. A man is involved in sexual relations with his female lover. Just prior to orgasm, the thought of his friend Bob pops into his head. This is the fourth time in a month that this has happened. In response to this, he becomes very upset and wonders whether or not he is gay. His sexual activity is terminated in order to avoid having to deal with this concern.


2. A mother is changing the diaper of her infant. As she lovingly looks down at this helpless child, the thought occurs to her to "take a pillow and smother him." In response to this thought, the mother panics and runs to another room to diminish the possibility of acting on this thought, because she feels that having the thought is tantamount to acting on it.

3. A student finishes a conversation with his favorite professor. For the next three hours the student reviews the conversation mentally to ascertain if he said anything that might have been offensive.

4. An altar boy in church notices a statue of the Virgin Mary. He has a fleeting thought passes about performing a sexual act on her. He is tormented endlessly, even though he has repeatedly confessed the thought to a priest and to his parents.

5. A young man notices that the word “suicide” possesses a significant repugnance. It is not that he is depressed; he feels that the word suicide “shouldn’t” stand out. He finds that, not only does encountering the word in print produce a tremendous amount of emotional tumult, but hearing it in his own thoughts becomes equally upsetting. Certain sounds also start to stand out as being unique and unsettling. He begins to spend a great deal of time wrapped up in his own thoughts attempting to arrange the word in a certain manner so that it possesses less significance. He becomes tormented by the possibility that the unique sounds surrounding him may linger on for eternity and determines that he must find some method to stop being reminded of their occurrence.

6. A woman survives emotional abuse from an overly controlling father. At 20, she leaves his house, and she’s elated. However, she develops an obsession. She decides that all objects, which remind her of him, are infused with his essence and, therefore, must be discarded. Although irrational, she feels that discarding anything related to him will keep her identity free from his influence. She feels that to completely free herself from him, she has to discard all objects that remind her of her father, even those that might have been “contaminated” by contact with his possessions. This effort to free herself from her father’s influence, becomes so encompassing that she has to avoid even mail from her siblings because her father might have come in contact with something that had come in contact with the mail.



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