Around the world, approximately 264 million people suffer from anxiety. In fact, anxiety is at the epicenter of many mental disorders. It is not only at the base of panic attacks and phobias, but also post-traumatic stress disorder and even major depression.
The presence of anxiety is usually a sign of greater clinical severity and predicts worse therapeutic results. In other words, anxiety disorders tend to be more severe and difficult to treat.
Currently, the main therapeutic strategies to treat anxiety are psychotherapy and anxiolytics, but more than a third of patients with anxiety, post-traumatic stress disorder or major depression do not respond to these conventional treatments.
The good news is that new neuropsychological approaches are being developed to restore proper functioning to key brain areas implicated in anxiety, depression, and post-traumatic stress disorders, such as the prefrontal cortex and amygdala. Such is the case of neuromodulation for anxiety, an increasingly interesting therapeutic option to complement psychotherapy and free oneself from pharmacological dependence.
Neuromodulation: what is it?
Neuromodulation techniques modify the electrical activity of specific areas of the brain by applying external magnetic or electrical fields. In transcranial magnetic stimulation (TMS), for example, a magnetic field is used to “carry” a short-duration pulse of electrical current to the brain, where it stimulates populations of neurons, primarily in the superficial regions of the cerebral cortex and the gray matter.
Since its first use in 1985, the potential of transcranial magnetic stimulation to temporarily interfere with cortical processing has become obvious. Basically, these magnetic pulses induce action potentials in neurons (specifically in their axons, which are more easily activated) and their repetition at low or high frequency inhibits or facilitates synaptic transmission and neuronal firing.
In some cases neuromodulation can “silence” neurons and in others add more “activity” to ongoing processing, although in practice its therapeutic power is more likely to come from a combination of both effects, depending on the intensity of the stimulation.
As a result, transcranial magnetic stimulation can directly change the activity patterns in certain brain structures, although it can also act more indirectly, generating changes in more distant areas, which will have a secondary effect on the entire neural network.
Is neuromodulation effective in relieving anxiety?
In addition to the genetic, hormonal, social and cognitive factors that trigger anxiety and mental disorders in general, a pathologically altered neural plasticity is also at their base. In other words, anxiety is accompanied by changes in the neural networks that cause many of the maladaptive behaviors.
Neuromodulation is a form of non-invasive brain stimulation, whose biochemical effects are prolonged over time, rebalancing maladaptive activity and functional connectivity between brain structures.
In fact, researchers from the University of Bordeaux analyzed 19 studies and concluded that “Neural stimulation was associated with a statistically significant reduction in the intensity of anxiety symptoms.”
Neuroscientists from the University of Milan also conducted a meta-analysis that included 7 investigations on the use of neuromodulation and concluded that “Non-invasive brain stimulation reduced levels of anxiety and depression, suggesting that it can alleviate clinical symptoms in patients with anxiety disorders.”
Is it a safe technique? How does it apply?
In the case of transcranial magnetic stimulation, is used an electromagnetic coil that emits magnetic pulses on the scalp, near the forehead. Those pulses painlessly stimulate nerve cells in the region of the brain that controls mood and anxiety.
In general, neuromodulation techniques for anxiety and depression are safe and well tolerated. However, in some people they can cause mild or moderate side effects that disappear over time, such as headache, discomfort in the area of stimulation, tingling sensation in the facial muscles and/or lightheadedness.
Professionals that use neuromodulation to treat disorders such as anxiety, depression and some addictions, explain that the duration of the treatment can vary from 5 to 40 minutes, depending on the problema and the way to address it.
In general, several neuromodulation sessions are carried out during a period of 4 or 6 weeks. Most patients respond very well to treatment, although after finishing the sessions or while they are received, it is advisable to undergo psychotherapy to learn how to manage situations that tend to generate anxiety and avoid future relapses.
Sources:
Gay, F. et. Al. (2022) Neuromodulation Treatments of Pathological Anxiety in Anxiety Disorders, Stressor-Related Disorders, and Major Depressive Disorder: A Dimensional Systematic Review and Meta-Analysis. Front Psychiatry; 13: 910897.
Brandl, F. et. Al. (2022) Common and specific large-scale brain changes in major depressive disorder, anxiety disorders, and chronic pain: a transdiagnostic multimodal meta-analysis of structural and functional MRI studies. Neuropsychopharmacology; 47: 1071–1080.
Vergallito, A. et. Al. (2021) Effectiveness of noninvasive brain stimulation in the treatment of anxiety disorders: a meta-analysis of sham or behaviour-controlled studies. J Psychiatry Neurosci; 46 (6): E592-E614.
Freire, R. C. et. Al. (2020) Neurostimulation in Anxiety Disorders, Post-traumatic Stress Disorder, and Obsessive-Compulsive Disorder. Advances in Experimental Medicine and Biology; 1191: 331-346.
Siebner, H. R. et. Al. (2009) How does transcranial magnetic stimulation modify neuronal activity in the brain? – Implications for studies of cognition. Cortex; 45(9): 1035–1042.
