A Scalpel-Free Dissection of the Past Present and Future of Non-Invasive Brain Stimulation

Non-Invasive Brain Stimulation

A Promising Frontier for Neurodegenerative Diseases and Cognitive Enhancement

With a growing aging population, the prevalence and burden of neurodegenerative diseases is only increasing.  Though there are various pharmacological and non-pharmacological methods for treating these conditions, there is a growing interest in non-invasive treatment options.  One such promising direction is the field of non-invasive brain stimulation or NIBS.  Since its inception in the mid-twentieth century, NIBS techniques have played a pivotal role in unraveling the intricacies of the human brain, uncovering therapeutic avenues, and opening a new frontier in cognitive enhancement.

The field of modern noninvasive brain stimulation can probably be traced back to the advent of Transcranial Magnetic Stimulation (TMS) by Barker and colleagues. This technique employs a small external coil that produces a strong magnetic field to stimulate the brain noninvasively.  This tool has been used for both research and therapeutic applications, helping to understand and treat a variety of neurological and psychiatric conditions.

By 2008, TMS was approved by the United States Food and Drug Administration (FDA) as a treatment for major depressive disorder.  Shortly thereafter, a variety of TMS devices were also approved for their use in cortical mapping.  These milestones highlight the possible therapeutic and research applications, as well as the robust efficacy and safety profiles of the technology. Since then, its therapeutic potential has expanded, with applications in stroke rehabilitation, pain management, and even the treatment of migraines. Momentus in its own right, the advent of TMS marks the beginning of the growing field of NIBS with its even greater reach and applicability.

Expanding the Horizons of Non-Invasive Brain Stimulation

Advancements in Techniques and Applications

Following TMS, the repertoire of NIBS techniques expanded with the development of transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS). Both of these methods use external currents to modulate neuronal activity, often activating or inactivating specific brain regions, based on the current used. Such techniques have been instrumental in various domains, from cognitive enhancement and pain management to psychiatric disorder treatment.

Another NIBS application is extremely low frequency and low-intensity electromagnetic field (ELF-EMF) stimulation. This technique leverages low-frequency (less than 100 Hz) and low-intensity (less than 10 G) electromagnetic fields to modulate brain function.  Such treatments have been shown to influence various physiological processes, including neuroplasticity, and may have potential therapeutic implications for conditions such as stroke,  Alzheimer's disease, and Multiple Sclerosis, among others.  As a subset of this, BrainQ’s treatment utilizes Electromagnetic Network Targeting Fields (ENTF), which use network signatures to determine treatment parameters, focusing the treatment toward the specific functional domain that is impaired.

Though semi-invasive, a landmark study published in the New England Journal of Medicine in 2018 demonstrated the efficacy of epidural stimulation in returning lower extremity function to paralyzed individuals, bringing the capabilities of NIBS to a new high. In this small study, an array of electrodes was implanted in the epidural space above the spinal cord below the site of injury and provided continuous electrical stimulation.  By doing so, researchers achieved voluntary lower extremity movement in individuals with complete motor paralysis. This use of epidural stimulation represented a significant leap forward in the treatment of spinal cord injuries and will pave the way for revolutionary advancements in rehabilitation medicine.

The contemporary application of NIBS techniques extends beyond just clinical treatments and into the realm of cognitive enhancement as well. For example, tDCS has been utilized to enhance memory and attention span in healthy individuals, offering intriguing insights into the human brain's potential. Furthermore, low-frequency EMF stimulation is being investigated for its potential in chronic pain management, offering a novel approach for conditions unresponsive to traditional therapies.

Non-Invasive Brain Stimulation of the Future

Potential for Remote Telemedicine and Precision Medicine Applications

With such an exciting history, the future of NIBS holds much promise and potential. One such area of exploration is the treatment of neurodegenerative disorders such as Alzheimer's and Parkinson's diseases via several NIBS modalities.  Moreover, the potential uses of NIBS may do so by alleviating symptoms and slowing the progression of these diseases, as well as by possible disease modification or reversal, presenting an exciting frontier for future research.  As well, though this is not appropriate for all NIBS modalities, the relative simplicity and safety of some of these applications offer additional avenues for remote telemedicine treatments, addressing a critical need in an industry where the manpower demands greatly outweigh the available supply and risk to patients is increased by in-person clinic visits. 

The field of NIBs may also have great implications on the related disciplines of neuro engineering and brain-computer interfaces; as our understanding of the neural circuitry underlying health and disease deepens, the integration of NIBS techniques with advanced neuroimaging could allow for precision neuromodulation, opening up the possibility for personalized neurological interventions.  This is the ultimate goal of our ENTF treatment, allowing for personalized and remote care for neurodegenerative diseases.

The evolution of noninvasive brain stimulation reveals an extraordinary journey that has transformed our understanding of the human brain and its potential. From the advent of TMS to the groundbreaking advancements in epidural and low-frequency EMF stimulation, NIBS techniques have continued to revolutionize neuroscience and clinical neurology.  The future of NIBS is packed with exciting possibilities and challenges; with continuous research and refinement, these techniques could reshape our understanding of the brain and offer unprecedented therapeutic and cognitive advancements.

Key Takeaways 

• NIBS techniques have greatly contributed to our understanding of the human brain.
• Transcranial Magnetic Stimulation (TMS) has been approved for depression and has expanded to other conditions like stroke rehabilitation, pain management, and migraines.
• NIBS techniques like tDCS, tACS, ELF-EMF stimulation, and epidural stimulation have shown promise in cognitive enhancement, pain management, and treating psychiatric and neurodegenerative disorders.
• The future of NIBS includes advancements in remote telemedicine and personalized interventions.
• Continuous research and refinement of NIBS techniques can lead to transformative neurological treatments.