Ultrasound to Manipulate Brain Functioning

I just recently mentioned about some potential future methods to manipulate brain functioning. I had talked about acoustic stimulation but was a little unsure of what that meant, so I did a little more digging and came up with a fairly recent patent that might shed some light on this concept. So it sounds like using ultrasound in conjunction with a magnetic field can modify neuron firing.

"A new method of stimulating active tissue is proposed by propagating ultrasound in the presence of a magnetic field. Since tissue is conductive, particle motion created by an ultrasonic wave will induce an electric current density generated by Lorentz forces."

"Focused ultrasound has been used to modify electrical currents in neuronal tissue. This has been done by a combined application of a magnetic field and an ultrasonic field to neuronal and other tissue in the body."

You can read more about a relatively recent patent of this technology at this web page. The authors of the patent mention the problem of using transcranial magnetic stimulation in conjuction with an MRI, which I hadn't considered.

"Also, there is a problem in using TMS together with fMRI, because TMS produces a magnetic signal that interferes with the magnetic field and consequently with the fMRI image."

Using ultrasound would allow brain manipulation with simultaneous real time brain imaging. This would allow scientists to immediately see the resulting effect of altering brain functioning. The so called focused ultrasound pulse is able to reach deeper into the brain. This is similar in concept to deep TMS. It also could enable a much greater focal accuracy (.5 - 2 mm) as well. This means you could target very small brain areas. I am pretty amazed that this would allow such targeting accuracy. This could lead to the development of much more refined treatments for various brain disorders.

"FUP is able to reach brain tissue much deeper, 2 or more centimeters into the brain, for example 2-12 cm. The FUP can also produce a focus of energy that will be only 0.5-2 mm. in diameter, as opposed to 2-3 cm. attainable by TMS. "

The patent mentions that different ultrasound frequencies can either excite neurons or inhibit neuron firing. So this is in principle similar to TMS. Scientist would be able to activate or deactivate almost any specific brain area at will.

"Low frequencies, below 300 Hz, will decrease the firing of the centers and inhibit or disrupt the neuronal circuits. High frequencies, 500 Hz to 5 MHz, will produce activation of firing of neuronal centers and activation of the circuits. In either case, the FUP will modify physiological properties in the circuits."

Through repeated stimulation of certain brain areas, this can change brain functioning for a longer period of time.

"Repeated application of the FUP to neuronal circuits will cause long-term or permanent changes to the circuits. The modification of the circuits using FUP will be used for the treatment of psychiatric, neurological and neuroendocrine disorders."

This has been patented, so I'm assuming it is possible to do. This could potentially overcome many of the current problems that plague TMS devices. It would allow scientists to get a better functionality map of the brain. They could knock down different regions temporarily to see the resulting effect. This method could also potentially treat a myriad number of brain disorders in the future. If anyone knows any more about this, please comment.