Obsessive-compulsive disorder (OCD) is a relatively well-known mental health condition affecting 1–3% of the population. It is characterised by obsessions with patterns or repeated behaviours as well as other obsessive tendencies such as precise and unaccommodating tidiness. Common treatment options for OCD include talking therapy (specifically cognitive behavioural therapy) and medication. However, did you know that in recent decades it has been revealed that you can use magnetic therapies to stimulate the brain in a way that reduces or prevents such behaviours?

Yes! A technique termed transcranial magnetic stimulation (TMS) is a form of non-invasive stimulation of the brain that has been shown to reduce some of the compulsive behaviours seen in people with OCD.

Read on to learn more about OCD, how it affects a person’s day-to-day life, what happens in the brain of an OCD person, and more about TMS and its application in treating these individuals!

What is OCD? 

OCD is a mental health condition, characteristically defined by its two major classes of symptoms: obsessions and compulsions. People with OCD frequently encounter obsessive thoughts. These are usually worrisome, anxiety-fuelling thoughts that won't leave their head. Some people often find themselves stuck with doubts, urges, images or worries that they can't stop thinking about, leading to feelings of distress and anxiety.¹ People with OCD also tend to form compulsions, in the form of repetitive behaviours or thoughts that may be carried out almost ritualistically, as a manner of keeping the obsessive thoughts at bay. 

While many people often think such obsessive thoughts, OCD individuals have little to no control over such thoughts and the inability to remove them from their mind causes lots of distress.¹

Symptoms of OCD

Common symptoms of OCD include specific or general obsessions, such as an obsession with perfection, in which the person may be excessively concerned with evenness, exactness, and symmetry. Many OCD individuals are obsessed with hygiene due to obsessive thoughts of contamination or germs - these people tend to compulsively wash their hands or even wear gloves and masks outside.²

People with OCD spend nearly an hour a day on their obsessive compulsive behaviours due to their repetitive nature. In that aspect, OCD severely diminishes the quality of life for such individuals, not to mention the anxiety caused by such thoughts having a negative effect on other aspects of their lives.

It is, however, important to note, that OCD is not the fault of the person affected by it. Mental health disorders are rooted in biology and specific neurological phenomena. Therefore, they cannot simply treated by “not worrying so much”, or “becoming mentally strong”. In fact, such statements are the cause of stigmatisation of mental health disorders, that have for so many centuries led to under-diagnosis and under-treatment of conditions like OCD.³

Causes and neurological basis of OCD

While the cause of OCD has not been decisively determined, research has revealed possible causes linked to trauma, neurobiology, and genetics.

Familial factors: Chances of OCD are increased, for example, if members of your family have OCD. However, it has not been determined whether this is because exposure to repetitive behaviours is imbibed into the patterns of an individual, or if there is a genetic component.⁴

Hyperactivity in certain regions of the brain: It is certain, however- through brain scans and neural studies - that people with OCD show differences in various neurological phenomena. Specific parts of the brain have been shown to exhibit hyperactivity - in other words, neurons in these parts of the brain remain more excited than in people without OCD.⁵

Serotonin imbalance: Serotonin (the so-called ‘happy hormone’) imbalances are also commonly seen in OCD individuals. Serotonin is the neurotransmitter used by some brain cells to communicate, low serotonin levels tend to trigger OCD symptoms.⁶

Imbalanced feedback loops: One hypothesis posits that some neural pathways in the brain, which create ‘feedback loops’ - become compromised due to imbalances in other pathways. Feedback loops are, in essence, branches of a pathway which signal that its function is occurring normally.⁵

Let’s say a molecule ‘Messenger X’ must travel along Pathway 1 from point A to point B. This pathway possesses a feedback loop which:

• Recognises that messenger X has completed its course from point A to point B
• Signals to point A to stop sending more of messenger X along pathway 1

If this feedback loop is faulty, messenger X is continuously produced and repeatedly traversing this pathway. In this theory, messenger X moving across pathway 1 again and again represents the obsessive presence of intrusive thoughts in the minds of OCD patients.^7,8As such, through analysis of the brain and various neurological/physiological phenomena occurring therein, science has revealed that there is a biological difference in the functioning of OCD brains.

Onset and diagnosis

Onset of OCD occurs most often at one of two stages of life - one of which is childhood OCD (at around 10 years of age) or what is known as adult-onset OCD which begins in early adulthood. Around half of childhood OCD cases do not continue into adulthood.⁵

OCD is diagnosed by a psychiatrist or healthcare provider qualified for such evaluations. When obsessions and compulsions cause major distress to an individual and interfere with the quality of their daily lives by taking up at least an hour a day, your healthcare professional will evaluate you through a physical exam and a psychiatric exam. A characteristic feature recognised as being a part of OCD, is the ability to recognise that the compulsive behaviours or obsessive thoughts/urges are unnecessary or excessive (‘egodystonic’ behaviours).^9,10

Traditional treatments and limitations

Current treatments include cognitive behavioral therapy (CBT)- this is a form of talking therapy in which obsessions are individually identified and the pattern of obsession leading to compulsion is challenged. The focus of the treatment is to guide the individual on how to deal with the thoughts, emphasising that it is not the thoughts that are the problem, but what you make of them.¹¹

CBT shows partial improvement in 75% of people who stick with the treatment, however, limitations arise:

• Participants are emotionally vulnerable, meaning they often feel misunderstood by the therapist, often questioning the therapist's ability or willingness to help
• Often a lack of collaboration results in reduced engagement, making therapy less effective or ineffective for service users
• CBT may not be suitable for people with more complex mental health disorders or learning disabilities due to its structured nature¹²
• When participants feel they do not understand the aspects of the therapy, they do not engage¹³

In conclusion, CBT often fails due to a disconnect between therapist and participant, and requires the full engagement and enthusiasm of both, which, with many people with OCD, or learning difficulties, is demanding.

Another form of treatment is selective serotonin reuptake inhibitors. These are antidepressants which alter chemical imbalances in the brain and increase serotonin levels. As mentioned, serotonin imbalances are one of the triggers for OCD symptoms. However, one must be on an SSRI course for over or up to 12 weeks before any improvement is seen.¹⁴ Additionally, being a medical intervention, it is an invasive method. SSRIs also cannot be taken by patients with other disorders.^15,16 SSRIs also have several side effects that can be avoided with the use of TMS.

Transcranial magnetic stimulation (TMS)

What is TMS and how does it work?

Transcranial magnetic stimulation, or TMS, is a non-invasive type of brain stimulation that has shown some success in the treatment of OCD. TMS works by stimulating the brain using magnetic induction. The application of a magnetic field to an electrically charged system induces the flow of current through that system. As neural impulses travel through the brain electrically, magnetic stimulation of a region of the brain can therefore activate neural networks.¹⁷

In TMS, an external device is applied close to the head over regions that have been determined to require increased activation. The device generates a high-intensity magnetic field in bursts towards the target region of the brain, stimulating its activity.¹⁸ The current thus produced stimulates the release of various neurotransmitters, including serotonin and dopamine. However, these fields only reach about 2-3 cm into the brain. 

History of TMS as a therapeutic tool

The treatment method was developed in 1985 by Barker and Colleagues as a device for the study of magnetic induction influencing brain activity.¹⁹ By the end of the 2000s, TMS had gained approval for the treatment of depression. It is now widely used for the treatment of various mental health disorders, particularly in cases where traditional methods and medication are ineffective or cause side effects.²⁰

How does TMS help treat OCD?

As mentioned earlier, the application of a magnetic field over targeted brain regions leads to increased neural activity, including improved serotonin and dopamine levels. 

To understand how TMS is useful for the treatment of OCD we must understand the following points:

• People who live with OCD experience reductions in their serotonin levels, which worsens the symptoms of their OCD⁶ 
• Specific regions of the brain have already been implicated in the symptoms of OCD - with respect to chemical imbalances or faulty neural pathways⁵
• TMS -
  • Can be targeted to specific regions of the brain
  • Increases neurotransmitter release (e.g., serotonin) in targeted regions
  • Improves neural activity in targeted regions

Essentially, this means that TMS can be used to magnetically stimulate the identified brain regions, improving neural activity in these regions and increasing serotonin release.TMS has been observed to improve OCD symptoms.²¹

What happens in a TMS session?

TMS is used to treat a variety of mental disorders apart from OCD, including depression, migraines, and smoking habits.²²

The type of TMS therapy you are given determines the outcome to some extent. TMS for OCD is often one of two types- either:

• rTMS (repetitive TMS): pulses of magnetic waves are delivered close to the surface of the brain
• dTMS (deep TMS): pulses of more intense, magnetic waves which reach deeper into the brain

These waves are applied over regions of the brain associated with OCD, including the dorsomedial prefrontal cortex (dmPFC), pre-supplementary motor area (pre-SMA), and bilateral and right dorsolateral prefrontal cortex (dlPFC), which has been shown to improve OCD symptoms.^23,24

Your healthcare provider will tailor a specific TMS session to your needs as required by your condition. The therapy is then carried out in multiple sessions for multiple weeks. The duration of each session varies from as little as five minutes to an hour. Around 20-30 sessions are carried out in total.^24,25

Limitations

TMS is a non-invasive procedure and can be carried out without any anaesthetics. The patient feels no pain but some discomfort may be felt. Side effects are not uncommon but are mild. These include: 

• Headache, and discomfort of the scalp
• Twitching of facial muscles
• Lightheadedness

In some rare cases, in people with other disorders, TMS may cause symptoms that are of more concern:

• Seizures (in patients with forms of epilepsy)
• Hypomania (in patients with bipolar disorders)

As such certain groups of people should not undergo TMS, including:

• People with metal implants/fragments in ears, eyes, or head
• People with a history of epilepsy
• People with stents in the head or neck
• People with magnetic implants or stimulators²⁴

Provide your healthcare provider with your medical history to ensure that you are eligible for TMS therapy.

FAQs

What is TMS?

TMS, or transcranial magnetic stimulation, is a non-invasive procedure which uses the application of magnetic waves to treat mental health conditions.

Can TMS cure OCD?

TMS has been shown to improve OCD symptoms within one month in 55% of people treated. 30% of people show complete remission and no longer have symptoms, but this depends on how well you respond to treatment

How long does TMS therapy last?

You are recommended to undergo 20-30 sessions, each lasting five minutes to an hour. The procedure is usually administered over a period of 5-6 months.

How does TMS treat OCD?

TMS increases brain activity in targeted regions of the brain. By applying the therapy to regions affected by OCD, you can increase serotonin production and modulate pathways that are faulty in OCD.

Summary

Transcranial magnetic stimulation (TMS) offers a potent alternative therapy for the treatment of OCD symptoms. With more than half of patients who undertake traditional OCD treatment not experiencing significant improvement, TMS signifies a hopeful option. TMS has been shown to be quite effective in the treatment of OCD patients. 45-55% of people who showed no improvement with conventional methods, experienced a reduction in symptoms within one month of TMS therapy.²⁴ After completion of their TMS course, 30% of people with OCD no longer experienced any of their obsessive or compulsive tendencies.²⁶

TMS therefore, poses as an effective non-invasive and low-risk alternative therapy for the treatment of OCD symptoms, alleviating the struggles people with OCD face, and offering the hope of a better quality of life.