The Science of Obsessive Compulsive Disorder (OCD)
Mental Health Awareness Series
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This article will explore a debilitating mental health illness - Obsessive Compulsive Disorder through the lens of science. OCD is a common neurobiological disorder, affecting around 2% of the population across globe, yet very misunderstood. There are a wide range of misconceptions about OCD, causing stigma and confusion around the disorder.
By increasing awareness and understanding of OCD, we can help reduce stigma, improve access to care, and make a meaningful difference in the lives of those affected by OCD. With this purpose in mind, this article will cover different aspects of OCD. Following list will summarise what to expect in this article :
What is OCD?
What are obsessions? List of common themes and examples of obsessions.
What exactly are compulsions?
What isn’t OCD? How to differentiate between Obsessive Compulsive Personality Disorder and OCD, a mental illness ?
Causes of OCD
Diving deep into anatomical and functional changes in OCD Brain
Role of Serotonin in OCD
Debunk common myths about OCD
This article is purely for educational purpose and not for self-diagnosis or self-treatment.
In the follow-up article, we will investigate the available treatment strategies and their underlying mechanisms. We will also discuss the directional advancement in the OCD treatment research and also touch upon the pitfalls. At the end, there will be recommendations for further reading! Stay tuned…
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1. What is OCD?
OCD is a mental disorder, as the name suggests, it is characterised by recurrent obsessions and compulsions that cause problems in information processing. Obsessions and compulsions typically consume a significant amount of time (e.g., more than one hour per day) and interfere with daily functioning.
The severity of OCD symptoms can be measured using the Yale–Brown Obsessive Compulsive Scale (Y-BOCS).
Another feature of OCD is that it is frequently comorbid with other psychiatric disorders, with approximately 70% of OCD patients comorbid for major depressive disorder (MDD), 20% phobia disorders, 14% substance abuse disorder, and 10% Tourette's syndrome.
2. What exactly are Obsessions ?
Thoughts, images, or impulses that occur over and over again and feel outside of the person’s control. Individuals with OCD do not want to have these thoughts and find them disturbing. In most cases, people with OCD realize that these thoughts are illogical.
Obsessions are typically accompanied by intense and uncomfortable feelings such as fear, disgust, uncertainty and doubt, or a feeling that things have to be done in a way that is “just right.”
In the context of OCD, obsessions are time consuming and get in the way of important activities the person values.
2.1 Obsessions often have themes to them, such as:
Fear of contamination or dirt
Doubting and having difficulty tolerating uncertainty
Needing things orderly and symmetrical
Aggressive or horrific thoughts about losing control and harming yourself or others
Unwanted thoughts, including aggression, or sexual or religious subjects
2.2 Examples of obsession signs and symptoms include:
Fear of being contaminated by touching objects others have touched
Doubts that you've locked the door or turned off the stove
Intense stress when objects aren't orderly or facing a certain way
Images of driving your car into a crowd of people
Thoughts about shouting obscenities or acting inappropriately in public
Unpleasant sexual images
Avoidance of situations that can trigger obsessions, such as shaking hands
3. What exactly are Compulsions ?
Repetitive behaviors or thoughts that a person uses with the intention of neutralizing, counteracting, or making their obsessions go away.
People with OCD realize this is only a temporary solution, but without a better way to cope, they rely on compulsions nonetheless.
In most cases, individuals with OCD feel driven to engage in compulsive behavior and would rather not have to do these time-consuming and often torturous acts. Rather than being a source of pleasure, people with OCD perform compulsions because they believe these rituals are necessary to prevent negative consequences and/or to escape or reduce anxiety or the presence of obsessions.
3.1 As with obsessions, compulsions typically have themes, such as:
Washing and cleaning
Checking
Counting
Orderliness
Following a strict routine
Demanding reassurance
3.2 Examples of compulsion signs and symptoms include:
Hand-washing until your skin becomes raw
Checking doors repeatedly to make sure they're locked
Checking the stove repeatedly to make sure it's off
Counting in certain patterns
Silently repeating a prayer, word or phrase
Arranging your canned goods to face the same way
4. What isn’t OCD?
Being a neat-freak, or a perfectionist, is not OCD. Liking something in a specific order, is not OCD. Liking things to be clean, is not OCD. These are the traits of Obsessive Compulsive Personality Disorder. You are in control of your thoughts and mostly you feel happy or relaxed after being a neat-treat or perfectionist. Let’s explore this in detail:
4.1 Obsessive Compulsive Personality Disorder
“Obsessing” or “being obsessed” are commonly used terms in everyday language. These more casual uses of the word mean that someone is preoccupied with a topic, an idea, or even a person. To be “obsessed” in this everyday sense doesn’t mean that a person has problems in their day-to-day living — there may even be a pleasurable component to their experience of being “obsessed.” For example, you can be “obsessed” with a new song you hear on the radio, but you can still meet your friend for dinner, get ready for bed in a timely way, get to work on time in the morning, etc., despite this obsession.
Similar to obsessions, not all repetitive behaviors or “rituals” are compulsions. This depends on the function and the context of the behavior. For example, bedtime routines, religious practices, and learning a new skill all involve some level of repeating an activity over and over again, but are usually a positive and functional part of daily life.
Similarly, arranging and ordering books for eight hours a day isn’t a compulsion if the person works in a library. The content of an everyday “obsession” can be more serious: for example, everyone might have had a thought from time to time about getting sick, or worrying about a loved one’s safety, or wondering if a mistake they made might be catastrophic in some way. While these thoughts look similar to what you would see in OCD, someone without OCD may have these thoughts, be momentarily concerned, and then move on.
In fact, research has shown that most people have unwanted intrusive thoughts from time to time, but in the context of OCD, these intrusive thoughts come frequently and trigger extreme anxiety that gets in the way of day-to-day functioning.
4.2 Now, let me clarify the difference with Obsessive Compulsive Personality Disorder and OCD ?
Below table summarises the difference between OCPD and OCD:
5. The OCD Cycle
Anxiety plays a crucial role in the maintenance of OCD. Obsessions trigger anxiety and distress, and performing compulsions temporarily reduces this anxiety. However, the relief is short-lived, and the cycle of obsessions and compulsions continues, reinforcing the belief that compulsions are necessary to prevent harm or reduce anxiety.
6. Causes of OCD
Genetic Relation
OCD has some genetic relation, especially mutation in the human serotonin transporter gene, hSERT which can make someone susceptible to OCD and can pass it to next generation. Though environment factors also play a major role.
Neuroanatomic Factors
Abnormal brain structure and activity
Too little serotonin for their nerve cells to communicate effectively
Environmental factors
Its association with secondary autoimmune triggers was introduced through the discovery of Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal infection (PANDAS) and Pediatric Acute onset Neuropsychiatric Syndrome (PANS). Autoimmune encephalitis and systemic autoimmune diseases or other autoimmune brain diseases, such as multiple sclerosis, have also been reported to sometimes present with obsessive-compulsive symptoms (OCS).
7. 1 Anatomical Changes in Brain
OCD is a mental disorder…so let’s figure out what happens in brain which leads to OCD.In individuals with OCD, specific brain regions and neural circuits demonstrate structural and functional changes. Research has suggested that the following brain areas and circuits are involved in OCD:
Orbitofrontal cortex (OFC): The OFC is involved in decision-making and emotional regulation. In people with OCD, this area often exhibits hyperactivity, which might contribute to the persistent intrusive thoughts and compulsions.
Anterior cingulate cortex (ACC): The ACC is involved in error detection, conflict monitoring, and emotional regulation. Altered activity in this region might contribute to the excessive doubt and anxiety experienced by individuals with OCD.
The basal ganglia are a cluster of subcortical nuclei deep to cerebral hemispheres. The largest component of the basal ganglia is the corpus striatum. The striatum coordinates multiple aspects of cognition, including both motor and action planning, decision-making, motivation, reinforcement, and reward perception. In short the striatum is involved in reward processing, habit formation, and the regulation of voluntary movement. Dysregulation in this area has been linked to the repetitive and habitual nature of compulsions in OCD.
Thalamus: The thalamus is a relay center for sensory and motor information. Abnormal functioning of the thalamus might contribute to the persistence of obsessions and compulsions in OCD.
7.2 Neurocognitive dysfunctions in OCD
Anatomical changes in different regions in the brain leads to misfiring in five important circuits - let’s understand them:
The fronto-limbic circuit (red) includes the amygdala and ventromedial prefrontal cortex (vmPFC) and is involved in producing emotional responses, such as fear and anxiety. Intolerance of uncertainty. the tendency to perceive and interpret uncertain or ambiguous situations as negative or threatening, a reduced ability to cope with uncertainty or to respond with impulsive or avoidance behaviors, and an excessive need to establish certainty
The sensorimotor circuit (green) includes the supplementary motor area (SMA), putamen, and thalamus, and is involved in producing and controlling motor behavior and the integration of sensory information. aversive or uncomfortable sensations or perceptions that drive repetitive behaviors, the sensation or perception (tactile, auditory, or visual domains) that things are “not-justright,” “incompleteness” symptoms,
The ventral cognitive circuit (yellow) includes the inferior frontal gyrus (IFG), ventrolateral prefrontal cortex (vlPFC), ventral caudate, and thalamus, and is involved in self-regulatory behavioral control.
The ventral affective circuit (purple) includes the orbitofrontal cortex, nucleus accumbens (NAcc), and thalamus, and is involved in processing and responding to reward. Altered reward responsiveness: alterations in the ability to anticipate, represent, and respond to rewards, such as blunted sensitivity to rewards and overgeneralization of punishment
The dorsal cognitive circuit (blue) includes the dorsolateral prefrontal cortex (dlPFC), dorsomedial prefrontal cortex (dmPFC), dorsal caudate, and thalamus, and is involved in executive functions (e.g., working memory, planning) and emotion regulation. Executive dysfunction: impairments in functions that are necessary for effective goal-directed behavior, including working memory (the ability to hold and manipulate information) and planning (the ability to organize thoughts and behaviors).
8. Deficiency of neurotransmitter, Serotonin!
Serotonin is a neurotransmitter, a brain messenger chemical that carries signals between nerve cells in the brain and is thought to be involved in regulating many functions, influencing emotions, mood, memory and sleep.
The brain is made up of millions of interconnected brain cells (neurons). Messages travel along these cells rather like electricity down a wire, but when the message reaches the end of the neuron, it has to jump the gap (synapse) to the next cell or group of cells. To do this the neuron releases tiny amounts of a neurotransmitter into the gap. Serotonin is one of these neurotransmitters.
These chemicals are sent out by one nerve cell into the space between it and the next. The next cell in line gets the message once those chemicals get to it from across the gap. That nerve cell then releases a chemical toward the next nerve cell so it gets the message.
The role of serotonin in OCD is not entirely understood, but research suggests that an imbalance in serotonin levels might contribute to the development and maintenance of OCD symptoms.
9. Let’s debunk some of the Myths around OCD
People who have OCD did not do anything to cause it. And it isn’t caused by the way parents raise their children. OCD is a neurobiological disorder — not a condition that is caused by action or inaction.
Myth 1: OCD is just about cleanliness
Fact: While some individuals with OCD do have obsessions and compulsions related to cleanliness and contamination, OCD can manifest in many different ways, such as intrusive thoughts about harm, religious or moral concerns, or an excessive need for symmetry and order.
Myth 2: OCD is a personality quirk
Fact: OCD is a serious mental health disorder that can cause significant distress and impairment in daily functioning. It is not a character flaw or a simple preference for orderliness.
Myth 3: People with OCD can "snap out of it”
Fact: OCD is not a choice, and individuals with the disorder cannot simply stop their obsessions or compulsions through willpower alone. Treatment, such as cognitive-behavioral therapy and medication, is often necessary to help manage symptoms.
Myth 4: OCD always involves visible compulsions
Fact: Not all compulsions are observable, as some may be mental acts, such as counting, repeating certain words, or silently praying. These "invisible" compulsions can be just as distressing and time-consuming as more visible behaviors.
Myth 5: OCD is rare.
Fact: OCD is more common than many people realize, affecting about 2-3% of the population at some point in their lives. The impact of the disorder can vary in severity, with some individuals experiencing more debilitating symptoms than others.
Myth 6: OCD is a woman’s disease.
Fact: It may seem but research shows it affects both gender at the same rate. According to the International OCD Foundation, OCD affects men, women, and children and of all ethnic, racial, and economic backgrounds at the same rate.
Myth 7: Bad Parenting causes OCD.
Fact: Bad parenting is rarely the cause. A complex interaction of factors causes OCD. Parenting – even when it’s imperfect doesn’t cause OCD. So, attempts to blame the parents can harm the treatment by making both parents and the child feel guilty. OCD is a complex diagnosis with many potential causes. People with history of trauma and neglect can also contribute to obsessions and compulsions.
Think you have an OCD ?
It is not possible to accurately self diagnose OCD. Find a psychiatrist nearby. Only a mental health specialist can determine whether your symptoms represent OCD or another condition.
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