OCD - Obsessions, Compulsions, Forms and Treatment

Written by Jacob W | Volunteer Research Manager | TBYM

---

What is OCD? (Obsessions and Compulsions)

Obsessive-Compulsive Disorder (OCD) is a mental health disorder characterised by those affected experiencing repetitive, negative intrusive thoughts centered around an individual’s fears (harm to self or others, magical/superstitious thinking) or impulsive taboo / forbidden thoughts (violence, sex, religion-centric etc). These are called “obsessions” (OCD UK, 2018a)

Obsessions can be irrational or ego-dystonic (inconsistent to a person's values). Despite experiencing taboo thoughts, it is important to make clear that these intrusive thoughts are not any reflection on the individual themselves. These intrusive thoughts are rooted within the fear of the idea, as opposed to an intention to act on them. 

Everyone experiences intrusive thoughts from time to time, however individuals experiencing OCD latch onto these thoughts and become unable to dismiss them in their thinking patterns. (OCD action, n.d)

Individuals experiencing OCD who face thoughts of a taboo nature experience a tremendous amount of fear and guilt about their obsessive thoughts (Hopkins, 2019), performing compulsive safety behaviours, or rituals (specific actions intended to reduce the distress caused by these thoughts). These are known as compulsions (Mind, 2023). The specific form of compulsion a person experiencing OCD performs is generally specific to the form of OCD that manifests. 

Compulsions can manifest in both covert and overt ways (OCD UK 2018b). Overt compulsions are observable rituals performed outwardly (examples include counting to a specific number, saying a special phrase, seeking reassurance from others, washing hands, performing a specific motor action). Covert compulsions are compulsions that are performed mentally (such as mentally counting, thinking a specific phrase, or thinking “good” thoughts instead). A common misconception of individuals that perform covert compulsions is that they are experiencing “Purely Obsessional” OCD (Pure-O) however this term is misleading, as individuals still perform a compulsive mental ritual to counteract their obsessive thoughts known as rumination (Williams et al., 2011) and may display subtle checking behaviours (OCD UK, 2018c)

Moreover, Individuals with OCD may feel “obligated” to perform their compulsion, so they can “prevent” their intrusive thoughts from becoming true. It is this perceived responsibility to protect themselves and those they care about that leads to the perpetuation of the OCD cycle. (International OCD foundation, 2023). Although compulsions may temporarily alleviate an individual's anxiety they reinforce the cycle of obsessive thought in future by placing attention on the importance of their thought. This causes the thought to occur more frequently, leading the individual to perform their compulsion more frequently - creating a vicious cycle of obsession to compulsion, worsening the OCD cycle.

A common compulsion within populations that experience OCD is the need to seek reassurance from those around them (OCD Action, n.d). Although providing reassurance to a sufferer may sound helpful in theory, in reality reassurance seeking is a form of safety behaviour that only provides temporary relief for the affected individual, and reinforces the habit of reassurance seeking behaviour. (Nightingale Hospital, 2025)

Unfortunately, no amount of reassurance will be able to reassure someone with OCD, and will only seek to worsen their OCD cycle. Instead, people with OCD are encouraged to acknowledge their thoughts, to understand their thoughts are not a reflection of them, and to challenge avoidant safety behaviours and compulsions through talking therapies such as Cognitive Behaviour Therapy (CBT) or Exposure and Response Prevention Therapy (ERP) - Top UK, (n.d).

Types of OCD

There are many forms of OCD. It is important to note that this is not a complete list. 

Contamination OCD (Penzel, 2000) is characterised by obsessive thoughts relating to germs and contamination. Individuals may feel “contaminated” until they have performed their compulsion a number of times (in this presentation hand washing compulsions are common). It is not limited to perceived dirt but also

• bodily excretions (urine, feces)

• bodily fluids (sweat, saliva, mucus, tears, etc.)

• household chemicals

• etc

Health Concern OCD (The Gateway Institute, 2023) is characterised by obsessive thoughts about the health of oneself or those they care about. A common fear resonating with many who experience Health OCD is the repetitive fear of developing / have already developed a life threatening illness. Compulsions within this form often present in the form of physical body exams (checking behaviours) or seeking medical reassurance.

Symmetry / Ordering OCD (AccessCBT, 2021) is characterised by obsessive thoughts that objects are not “quite right” and compulsions that follow through arrangement of such objects until they are “right”. This form of OCD is perhaps the most misunderstood. Many people who do not experience OCD firsthand equate OCD to a “quirk” for liking something a specific way and that anyone can be “a bit OCD”. In reality the compulsion to re-arrange objects is driven by obsessive thoughts that are deeply uncomfortable or distressing for the affected individual, and are performed specifically to alleviate these thoughts. 

Checking OCD (OCDTypes, 2019) is characterised by obsessive thoughts surrounding the checking of objects multiple times even if the object has been previously checked. The main difference between people who experience this type of OCD and those who do not is that people who experience checking OCD will feel compelled to continue checking. In such cases the need to check is exacerbated when not checking could lead to a perceived harm in the eyes of the sufferer. For example checking the door is locked or checking the stove is off (where both cases could have adverse consequences). 

Harm OCD (Penzel, 2004) is characterised by obsessive thoughts where individuals worry they are going to harm themselves or others. Individuals experiencing harm OCD may have intrusive thoughts relating to

• Violence towards others

• Morbid actions

• Acting Sexually inappropriate

These intrusive thoughts are extremely distressing for people with harm OCD, as they begin to question their own morality - it is important to distinguish that people with OCD are no more likely to commit violence or act out their intrusive thoughts than anyone else. 

People with OCD can experience multiple other forms throughout their life. For all forms of OCD It is not the thoughts that therapies aim to challenge but rather challenge a person's response to them (performing their safety behaviours / compulsions to alleviate the anxiety, reinforcing the OCD cycle)

Treating OCD

The treatment for OCD is not to challenge someone's intrusive thoughts. Everyone experiences intrusive thoughts whether they experience OCD or not. It is how an individual responds to their intrusive thoughts that therapies aim to challenge. Cognitive Behavioural Therapy (CBT) alongside Exposure Response Prevention (ERP) therapy are traditional therapies administered to help those living with OCD.  

CBT is a form of talking therapy that has been demonstrated to be successful in tackling phobias, anxiety and OCD. Specific therapeutic plans are often subjective to the individual and their unique challenges, however all CBT treatment plans for OCD aim to challenge maladaptive thinking and behaviours that reinforce OCD. CBT is intended to be a short term therapy that equips the patient to eventually be able to maintain their OCD independently (OCDUK, 2018d). Because patients with OCD fear what will happen if they don’t perform their compulsions (subsequently never confronting their fear) a key aspect of the therapy is encouraging patients to resist performing their compulsions. This will teach patients that even if they do not perform their compulsions, their obsessions do not become true. Teaching people with OCD to resist their compulsions in conjunction with acknowledging their intrusive thoughts are not the problem, helps to break the OCD cycle over time (BeyondOCD, 2019)  

Within an OCD treatment plan, Exposure and Response Prevention (ERP) may also play a role. ERP aims to slowly help a person overcome their fears by confronting them in gradual steps. For people with OCD, certain stimuli can trigger intrusive thoughts (for example an individual with OCD contamination may find locations like bathrooms to trigger obsessions about contamination). The therapist would therefore encourage that individual in smaller steps to challenge their fear without reinforcing their compulsions (looking at pictures of bathrooms, stepping inside a bathroom, touching a sink in a bathroom etc) until the stimuli no longer causes distress.  (OCDUK, 2018e) It aims to teach patients that their OCD intrusive thoughts don’t become true, even when they don’t perform their compulsions - this is called habituation. (BeyondOCD, 2019)