Transcranial Magnetic Stimulation – The Science


Depression is a psychiatric condition that can severely impact quality of life. Symptoms of depression include a loss of interest in previously pleasurable activities, sadness, hopelessness, feelings of worthlessness, guilt, anxiety, and irritability (1). As at least 17 million US adults struggle with depression, understanding how this condition progresses is essential to finding novel treatment options for this patient population (2). Conventional treatments for depression include psychological therapy and pharmacological antidepressant medications such as selective serotonin reuptake inhibitors (SSRIs), serotonin and noradrenaline reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), and electroconvulsive therapy (ECT) (3). Many of these pharmacological therapies have significant drawbacks and can cause the development of severe side effects such as anxiety, insomnia, nausea, sleepiness, dizziness, sexual difficulties, and weight gain (4). In addition to these side effects, traditional depression treatments may fail to provide adequate symptom relief for a population of patients struggling with depression – commonly called treatment resistant depression. In the search to address this failure of conventional depression treatments, researchers have discovered TMS Therapy as a novel treatment option for depression that provides profound and lasting symptom relief with minimal risk.


 Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation therapy used to treat psychiatric disorders like depression, migraines, and obsessive compulsive disorder (5, 6). In order to understand how TMS can provide significant and lasting depression symptom relief, it is essential to discuss how brain function is altered in patients with depression. 

Although the exact mechanisms of how depression progresses are not completely understood, several significant structural alterations have been identified in brain regions of depressive patients involved in mood regulation including the frontal lobe, hippocampus, temporal lobe, thalamus, striatum and amygdala (7). In patients with depression, these brain areas show reduced activity and may even become inactive (8). Further, research suggests that depression may be caused by changes to connections between brain cells (neuronal circuits) involved in the interaction of multiple brain regions (7). As both the structural connections between brain cells (neurons) and between brain areas are formed and fine-tuned by neurotransmitter actions, alterations in neurotransmitter concentrations have been widely accepted to play a role in depression pathology (9). Neurotransmitters are chemical substances that are released by brain cells in response to stimulation. Some neurotransmitters are excitatory, meaning they cause the activation of connecting neurons, and some neurotransmitters are inhibitory, meaning they inhibit a response in connecting neurons. In patients with depression, the concentration of certain neurotransmitters are known to be significantly altered (9).

TMS involves the application of targeted magnetic pulses to the superficial layers of the brain. This magnetic field is able to induce small electrical currents that stimulate nerve cells in mood-controlling areas of the brain (7, 8, 9, 13, 14). These small electrical currents are powerful enough and precise enough to elicit an activating signal in brain cells to release more neurotransmitters and therefore can increase the activity of connecting neurons. TMS is able to address the neurotransmitter imbalance associated with depression by stimulating targeted neurotransmitter release in mood-controlling areas of the brain (8). 


At Hudson Medical, we use the NeuroStar TMS system because it is a noninvasive treatment option for patients with depression that has extensive clinical trial data demonstrating its strong safety and effectiveness profiles. The NeuroStar TMS system is an FDA-cleared cutting-edge therapy designed to target multiple pathologies associated with depression. In addition to directly stimulating superficial brain regions involved in mood regulation, the NeuroStar TMS system is able to activate deeper brain regions which causes secondary activation of neurotransmitter centers that elicits activation of other brain regions involved in controlling mood. 

During the NeuroStar TMS Therapy treatment sessions, a physician will place a small magnetic coil lightly on the patient’s head. As treatment begins, the patient will hear a clicking sound and will feel a tapping sensation. Treatment sessions last between 20 and 40 minutes, and as there are no sedatives involved in the NeuroStar TMS Therapy treatments, the patient’s alertness is not altered. Patients are free to resume daily activities as soon as the session concludes. At Hudson Medical, we deliver NeuroStar TMS Therapy within a course of 4 to 6 weeks, but patients often report symptom improvement as soon as 2 weeks. 

Many studies have demonstrated that NeuroStar TMS Therapy provides a statistically and clinically meaningful and long-lasting benefit for patients with depression (14, 15, 16, 17). Symptom improvement in mood, days of experiencing depression and engagement in socializing have been reported as early as 2 weeks following NeuroStar TMS Therapy (18). The effectiveness of NeuroStar TMS Therapy has been demonstrated in over 65 clinical studies (13). These studies have shown that 83% of patients treated with NeuroStar TMS Therapy showed significant improvements in depression symptoms, and 62% of patients reported symptom relief lasting over 12 months (15, 17). NeuroStar TMS Therapy is not a pharmacological antidepressant medication, so it does not have any of the side effects associated with these traditional treatments (9, 19). The most common side effect associated with NeuroStar TMS Therapy is mild to moderate pain or discomfort that typically subsides within the first week of treatment (15).

At Hudson Medical, we are excited to offer NeuroStar TMS Therapy technology because it provides significant and lasting symptom relief for patients with depression through noninvasive magnetic stimulation. As NeuroStar TMS Therapy is FDA-cleared and demonstrates a strong safety and efficacy profile, the potential benefits for patients struggling to find symptom relief with conventional treatments are far-reaching. Extensive clinical trial data supports the use of TMS Therapy for treatment of depression and provides evidence for the powerful impact this therapy can have on the quality of life of patients struggling with depression. To learn more about TMS Therapy as a treatment for depression, click here → 


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