Playing the Field

Much of what we have covered in this publication since its founding five years ago relates to implanted electrodes that deliver stimulation to the brain and other portions of the nervous system. In this issue, we consider two forms of stimulation that do not require implanted electrodes. These are transcranial magnetic stimulation and slow wave electrical fields.

As NBR senior technical editor Warren Grill points out in his two articles on page 1 of this issue, both technologies offer promise for treating a variety of neurological and psychiatric disorders. In the case of magnetic stimulation, Neuronetics Inc.’s Neurostar system is in a good position to benefit from studies that indicate the effectiveness of rTMS in the treatment of movement disorders or ALS. Just as manufacturers of deep brain stimulation systems are gearing up to transform their neuromodulation devices from treating movement disorders to treating psychiatric disorders, Neuronetics may be able to execute the reverse transformation.

The effect that magnetic stimulation has on cortical excitability opens up many potential avenues of therapeutic intervention. In addition to the treatment options offered by rTMS alone, it may be that combination therapies merging magnetic stimulation with drug delivery might offer a way to enhance the effect of drug action on a local area of the brain. And as NBR editorial director David Pope points out in his profile of Nexstim on page 6 of this issue, magnetic stimulation in combination with EEG recording offers a powerful new neurosensing tool.

The development of applied electric fields as a treatment for neurodegenerative disorders, though much less progressed than devices based on magnetic fields, further expands the range of tools that neurotechnology may someday offer clinicians. The use of slow-wave stimulation devices during a patient’s sleep might prove to be less invasive than implanted neuromodulation devices and more reliably administered than certain drug therapies. The technology also raises the specter of a device that could aid nonimpaired individuals with learning tasks and thereby open neurotechnology markets to a much wider population than just those with neurological disorders.

But lest we fast forward too far in our thinking, let us not lose sight of the proven benefits that implanted neuromodulation devices have delivered to thousands of individuals with neurological diseases and disorders who otherwise would have no alternative. The specificity and precise targeting of devices such as DBS systems and cochlear implants will not likely be matched by field-generating devices for a very long time. Still, the availability of a range of neurotechnology devices that can deliver stimulation globally, regionally, or locally will offer clinicians and patients a range of choices that they can tailor to suit their needs.

James Cavuoto
Editor and Publisher