Future Transcranial Magnetic Stimulation Devices

I came across some interesting patent (applications) about potential future transcranial magnetic stimulation devices in a forum. This first patent uses magnetic fields coupled with what sounds like acoustic stimulation. I'm a little unsure of what exactly that means, but it sounds like this could potentially enable scientists to stimulate very small (1 cm) structures located deep within the brain. I assume this would allow a much greater focal accuracy and targeting ability than the deep transcranial magnetic stimulation I previously mentioned on this blog. Deep TMS may stimulate a larger brain area so it may be somewhat limited in its utility for certain brain disorders.

"A system is disclosed for the diagnostic or therapeutic treatment of a patient's neural tissues. The system includes at least a means to directly or indirectly acoustically expose or acoustically displace at least a first tissue portion. The system further includes a means to impose, directly or indirectly, an electromagnetic, electrical, magnetic or optical field on at least a second neural tissue portion. The combined or cooperative action of the acoustic exposure/displacement and the field, whether sequentially or simultaneously applied, causes at least one diagnostically or therapeutically useful mechanism."

The second patent has some information about "stereotactic transcranial magnetic stimulation" (sTMS). This also sounds similar in principle to Brainsway's deep transcranial magnetic stimulation. Instead of having an electromagnetic field generated from a single coil, they use multiple coils with 3 on the sides of the head and one on the top of the head. This would mean there would be less unbearable stimulation of more cortical brain areas. The problem with a single coil is that the magnetic field would need to be way too high to stimulate deeper brain structures. So brain areas near to the surface of the brain would be stimulated too much, leading to pain and potentially seizures.

"The present invention provides for Stereotactic Transcranial Magnetic Stimulation (sTMS) at predetermined locations with the brain or spinal cord and incorporates an array of electromagnets arranged in a specified configuration where selected coils in the array are pulsed simultaneously. Activation of foci demonstrated by functional MRI or other imaging techniques can be used to locate the neural region affected. Imaging techniques can also be utilized to determine the location of the designated targets."

So this stereotactic transcranial magnetic stimulation would likely have more focal accuracy and would also be coupled with real time brain imaging. This would allow scientists to simultaneously manipulate brain functioning and watch the resulting effects on an fMRI.

"Several patents and patent applications relate to such areas as electromagnetic coil design, simultaneous monitoring of EEG, simultaneous monitoring with functional MRI, and specific clinical applications."

The third patent has a coil that is constantly moving around the head. This would mean that no single area on the surface of the brain would be stimulated too much. This would also avoid over stimulation of surface brain areas and allow researchers to target deeper structures.

"Techniques for applying electromagnetic energy to deep, targeted areas without overwhelming other areas are provided. One or more coils are moved relative to a target area and magnetic fields are applied to the target from multiple coil locations. As a result, the aggregate electromagnetic energy applied to the target over time is greater than surrounding areas. Additionally, a model for testing and treatment planning is provided."

If these transcranial magnetic stimulation devices get patented they may have the potential for improved brain manipulation. They may serve as a new treatment modality in conjunction with the numerous other methods of changing brain chemistry that are already available.